Re: [Repeater-Builder] Re: Antenna question
G7-144 top-mounted at 60 feet for four years. I would watch the wobble when the wind blew and heard the crackling. I thought the lower phasing coil had worked loose at the studs. Not so. When I brought it down I discovered the four pins at the both the top and bottom of the lower phasing coil were missing and the outer tube was providing very little support. The inner assembly was holding the top portion on. W3ML wrote: Thanks everyone for the advice. When we got the antenna it had been up for 10 years or more at 350 feet. The fiberglass on the coil section was practically destroyed and the joints were very loose. We cleaned all the corrosion off the metal, re-fiber-glassed the section to seal it and used no-ox. Then when it was re-assembled, I sprayed it with clear polyurethane and then screwed the sections together to try and tighten them up besides having the hose clamps on them. It still wobbles and I believe there is something wrong inside the fiber-glassed section and that is what is causing some or all the trouble with noise on incoming signals. Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: mailto:repeater-builder-dig...@yahoogroups.com mailto:repeater-builder-fullfeatu...@yahoogroups.com * To unsubscribe from this group, send an email to: repeater-builder-unsubscr...@yahoogroups.com * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: Antenna question
It's worth giving the latest Hustler G7 G6 (the ones with Aluminum, not all fiberglass) Antennas a revised look. Some of the early G6 G7 Antennas I have here have fairly thin tube thickness. The latest replacement same model antennas are much better built. s. AA8K73 GMail aa8...@... wrote: G7-144 top-mounted at 60 feet for four years. I would watch the wobble when the wind blew and heard the crackling. I thought the lower phasing coil had worked loose at the studs. Not so. When I brought it down I discovered the four pins at the both the top and bottom of the lower phasing coil were missing and the outer tube was providing very little support. The inner assembly was holding the top portion on. W3ML wrote: Thanks everyone for the advice. When we got the antenna it had been up for 10 years or more at 350 feet. The fiberglass on the coil section was practically destroyed and the joints were very loose. We cleaned all the corrosion off the metal, re-fiber-glassed the section to seal it and used no-ox. Then when it was re-assembled, I sprayed it with clear polyurethane and then screwed the sections together to try and tighten them up besides having the hose clamps on them. It still wobbles and I believe there is something wrong inside the fiber-glassed section and that is what is causing some or all the trouble with noise on incoming signals.
[Repeater-Builder] Re: Antenna question
Since no one else has mentioned them I'll say take a look at the Hustler Spirit series antennas. Built similar to Stationmasters without the charging you for the name price. http://www.new-tronics.com/main/html/base_spirit.html Dan N8DJP --- In Repeater-Builder@yahoogroups.com, W3ML w...@... wrote: Now I realize that the DB type antenna is the best, but we do not have 800 bucks to buy one. You can do FAR better than that price. Primus Electronics, Joliet, IL. 800.435.1636. I have no connection with them other than being a very satisfied customer. Laryn K8TVZ
RE: [Repeater-Builder] Re: Antenna question
After installing some Hustler Spirit HD antennas in snow and ice conditions, and visiting the site to see several inches of radial ice everywhere, I became a dealer for them. They are built after the order to frequency. I ordered a 420 9 dB HD Omni, and a 440 9 dB Omni, and the 420 antenna was physically longer when compared side by side. Makes sense, but it's nice they are not using a one size fits all fiberglass case. I won't have to be worrying about replacing the Spirit Antennas for a long time, while I enjoy good coverage from the antennas. I have a statement that I always share: When you buy quality, it only hurts once. Bill Hudson W6CBS From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Dan Hancock Sent: Monday, October 12, 2009 4:16 AM To: repeater builders Subject: [Repeater-Builder] Re: Antenna question Since no one else has mentioned them I'll say take a look at the Hustler Spirit series antennas. Built similar to Stationmasters without the charging you for the name price. http://www.new-tronics.com/main/html/base_spirit.html Dan N8DJP --- In Repeater-Builder@yahoogroups.com, W3ML w...@... wrote: Now I realize that the DB type antenna is the best, but we do not have 800 bucks to buy one. You can do FAR better than that price. Primus Electronics, Joliet, IL. 800.435.1636. I have no connection with them other than being a very satisfied customer. Laryn K8TVZ
RE: [Repeater-Builder] Re: Antenna question
You all (well, everyone who's been here a while) know my general loathing for fiberglass stick antennas, since our lightning here turns them into pretty white bits of fiberglass blowing around the top of the mountain by the time you realize something's wrong with the repeater... But... after all the good comments about the Hustler Spirit antennas, if I *had* to use a fiberglass stick, it'd be first in line in the spreadsheet for cost/benefit analysis! :-) Otherwise, 99.9% of the time, it's Sinclair folded dipole arrays for me. The heavy-duty ones, not the wimpy little ones. (GRIN!) And to the guy who just showed up saying he has always wanted to build a repeater... yeah, me too... so I started volunteering with a group that needed some help years ago, and now I have repeaters coming out my ears. No need to build your own... in most areas there's PLENTY of repeaters that aren't performing up to spec, and/or need some TLC. Getting involved is step one, step two is shelling out real money for your own test gear, and once you have that... you're sucked in forever. And not just for your machines, it's like the bumper sticker you see on pickup trucks... Yes, this is my pickup truck. No I won't help you move. LOL! Can change that to... Yes, this is my service monitor. No I won't help you tune your duplexer. Haha... of course, reality is... you will. 'Cause you're a good ham... just make 'em bring beer over... and save the beer for AFTER you've done the tuning... -- Nate Duehr, WY0X n...@natetech.com On Mon, 12 Oct 2009 11:04 -0700, Bill Hudson w6...@pacbell.net wrote: After installing some Hustler Spirit HD antennas in snow and ice conditions, and visiting the site to see several inches of radial ice everywhere, I became a dealer for them. They are built after the order to frequency. I ordered a 420 9 dB HD Omni, and a 440 9 dB Omni, and the 420 antenna was physically longer when compared side by side. Makes sense, but it’s nice they are not using a one size fits all fiberglass case. I won’t have to be worrying about replacing the Spirit Antennas for a long time, while I enjoy good coverage from the antennas. I have a statement that I always share: “When you buy quality, it only hurts once.” Bill Hudson W6CBS From: repeater-buil...@yahoogroups. com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Dan Hancock Sent: Monday, October 12, 2009 4:16 AM To: repeater builders Subject: [Repeater-Builder] Re: Antenna question Since no one else has mentioned them I'll say take a look at the Hustler Spirit series antennas. Built similar to Stationmasters without the charging you for the name price. http://www.new- tronics.com/main/html/ base_spirit.html Dan N8DJP --- In repeater-buil...@yahoogroups. com, W3ML w...@... wrote: Now I realize that the DB type antenna is the best, but we do not have 800 bucks to buy one. You can do FAR better than that price. Primus Electronics, Joliet, IL. 800.435.1636. I have no connection with them other than being a very satisfied customer. Laryn K8TVZ References 1. http://groups.yahoo.com/group/Repeater-Builder/message/33231;_ylc=X3oDMTM1aWg0MnJuBF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEbXNnSWQDOTQ5MzkEc2VjA2Z0cgRzbGsDdnRwYwRzdGltZQMxMjU1MzcwNjg5BHRwY0lkAzMzMjMx 2. http://groups.yahoo.com/group/Repeater-Builder/post;_ylc=X3oDMTJwNWQ3bWptBF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEbXNnSWQDOTQ5MzkEc2VjA2Z0cgRzbGsDcnBseQRzdGltZQMxMjU1MzcwNjg5?act=replymessageNum=94939 3. http://groups.yahoo.com/group/Repeater-Builder/post;_ylc=X3oDMTJkdGZ0MzY3BF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDbnRwYwRzdGltZQMxMjU1MzcwNjg5 4. http://groups.yahoo.com/group/Repeater-Builder/messages;_ylc=X3oDMTJkdGY2aWVkBF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDbXNncwRzdGltZQMxMjU1MzcwNjg5 5. http://groups.yahoo.com/group/Repeater-Builder/files;_ylc=X3oDMTJlZW91bzYzBF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDZmlsZXMEc3RpbWUDMTI1NTM3MDY4OQ-- 6. http://groups.yahoo.com/group/Repeater-Builder/photos;_ylc=X3oDMTJkNGdsZXVjBF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDcGhvdARzdGltZQMxMjU1MzcwNjg5 7. http://groups.yahoo.com/group/Repeater-Builder/links;_ylc=X3oDMTJlN2VtM3M0BF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDbGlua3MEc3RpbWUDMTI1NTM3MDY4OQ-- 8. http://groups.yahoo.com/group/Repeater-Builder/members;_ylc=X3oDMTJkYWdoMWc1BF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDbWJycwRzdGltZQMxMjU1MzcwNjg5 9. http://groups.yahoo.com/;_ylc=X3oDMTJjZ285b2EwBF9TAzk3NDc2NTkwBGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDZ2ZwBHN0aW1lAzEyNTUzNzA2ODk- 10. http://groups.yahoo.com/group/Repeater-Builder/join;_ylc=X3oDMTJlZWM5cHQ4BF9TAzk3NDc2NTkwBGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDc3RuZ3MEc3RpbWUDMTI1NTM3MDY4OQ
RE: [Repeater-Builder] Re: Antenna question
Nate—et al, Fortunately on the left coast we don’t really have a lightening problem AND since our sites are all within view of the ocean, I don’t do anything but fiberglass OR coated folding dipoles, aluminum does not like salt air at all. And as Nate says—all you have to do is look around—and you will end up on a repeater committee or team—it started for me in the late 1960’s when we founded the Northeast FM Repeater Assn, and then Phila’s Para, then on to Cincy, and the same thing, make friends, show you know a little, have a Cushman and are you ever popular. Now on the left coast, this has happened twice—once near San Jose and now in Santa Barbara—LOTS of repeaters, very few folks who know how to make them talk and keep them talking—it is a lot of fun, and rewarding, and yes it costs money out of my own pocket here and there but that is what I like to do—build em and keep em running—let someone else use them! Andy W6AMS From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Nate Duehr Sent: Monday, October 12, 2009 4:12 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: Antenna question You all (well, everyone who's been here a while) know my general loathing for fiberglass stick antennas, since our lightning here turns them into pretty white bits of fiberglass blowing around the top of the mountain by the time you realize something's wrong with the repeater... But... after all the good comments about the Hustler Spirit antennas, if I *had* to use a fiberglass stick, it'd be first in line in the spreadsheet for cost/benefit analysis! :-) Otherwise, 99.9% of the time, it's Sinclair folded dipole arrays for me. The heavy-duty ones, not the wimpy little ones. (GRIN!) And to the guy who just showed up saying he has always wanted to build a repeater... yeah, me too... so I started volunteering with a group that needed some help years ago, and now I have repeaters coming out my ears. No need to build your own... in most areas there's PLENTY of repeaters that aren't performing up to spec, and/or need some TLC. Getting involved is step one, step two is shelling out real money for your own test gear, and once you have that... you're sucked in forever. And not just for your machines, it's like the bumper sticker you see on pickup trucks... Yes, this is my pickup truck. No I won't help you move. LOL! Can change that to... Yes, this is my service monitor. No I won't help you tune your duplexer. Haha... of course, reality is... you will. 'Cause you're a good ham... just make 'em bring beer over... and save the beer for AFTER you've done the tuning... -- Nate Duehr, WY0X n...@natetech.com On Mon, 12 Oct 2009 11:04 -0700, Bill Hudson w6...@pacbell.net wrote: After installing some Hustler Spirit HD antennas in snow and ice conditions, and visiting the site to see several inches of radial ice everywhere, I became a dealer for them. They are built after the order to frequency. I ordered a 420 9 dB HD Omni, and a 440 9 dB Omni, and the 420 antenna was physically longer when compared side by side. Makes sense, but it’s nice they are not using a one size fits all fiberglass case. I won’t have to be worrying about replacing the Spirit Antennas for a long time, while I enjoy good coverage from the antennas. I have a statement that I always share: “When you buy quality, it only hurts once.” Bill Hudson W6CBS From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Dan Hancock Sent: Monday, October 12, 2009 4:16 AM To: repeater builders Subject: [Repeater-Builder] Re: Antenna question Since no one else has mentioned them I'll say take a look at the Hustler Spirit series antennas. Built similar to Stationmasters without the charging you for the name price. http://www.new-tronics.com/main/html/base_spirit.html Dan N8DJP --- In Repeater-Builder@yahoogroups.com, W3ML w...@... wrote: Now I realize that the DB type antenna is the best, but we do not have 800 bucks to buy one. You can do FAR better than that price. Primus Electronics, Joliet, IL. 800.435.1636. I have no connection with them other than being a very satisfied customer. Laryn K8TVZ
RE: [Repeater-Builder] Re: Antenna question
I’d like to chime in here as well… I also agree that your first venture into repeaters should be as an assistant Trustee (or something similar) for your local ham club. Doing this will help you gain necessary experience and knowledge before you try to venture on your own. It will also allow you time to put together some of the test instruments necessary for building and testing repeaters This is how I got started, but ended up getting a baptism of fire when the repeater went down and no one else was available to assist me. In the end, I wound up being the primary Trustee. As I learned how to repair and improve the repeater, I gained valuable knowledge which allowed me to try to “roll my own” for 900 MHz. The homebrew was on the air for nearly 2 years before I acquired a commercial repeater station to replace it with. The homebrew is still in the shack, and I have plans to put it back on the air in the future, but no time schedule has been set. Take your time – you have a lifetime of fun (and accompanying headaches) ahead of you! Mark – N9WYS From: Repeater-Builder@yahoogroups.com On Behalf Of Andrew Seybold Nate—et al, Fortunately on the left coast we don’t really have a lightening problem AND since our sites are all within view of the ocean, I don’t do anything but fiberglass OR coated folding dipoles, aluminum does not like salt air at all. And as Nate says—all you have to do is look around—and you will end up on a repeater committee or team—it started for me in the late 1960’s when we founded the Northeast FM Repeater Assn, and then Phila’s Para, then on to Cincy, and the same thing, make friends, show you know a little, have a Cushman and are you ever popular. Now on the left coast, this has happened twice—once near San Jose and now in Santa Barbara—LOTS of repeaters, very few folks who know how to make them talk and keep them talking—it is a lot of fun, and rewarding, and yes it costs money out of my own pocket here and there but that is what I like to do—build em and keep em running—let someone else use them! Andy W6AMS
RE: [Repeater-Builder] Re: Antenna question
Hey - and everybody should be nice to Nate today - it's his birthday today - Monday October 12, 2009 Bill Hudson _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Nate Duehr Sent: Monday, October 12, 2009 4:12 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: Antenna question You all (well, everyone who's been here a while) know my general loathing for fiberglass stick antennas, since our lightning here turns them into pretty white bits of fiberglass blowing around the top of the mountain by the time you realize something's wrong with the repeater... But... after all the good comments about the Hustler Spirit antennas, if I *had* to use a fiberglass stick, it'd be first in line in the spreadsheet for cost/benefit analysis! :-) Otherwise, 99.9% of the time, it's Sinclair folded dipole arrays for me. The heavy-duty ones, not the wimpy little ones. (GRIN!) And to the guy who just showed up saying he has always wanted to build a repeater... yeah, me too... so I started volunteering with a group that needed some help years ago, and now I have repeaters coming out my ears. No need to build your own... in most areas there's PLENTY of repeaters that aren't performing up to spec, and/or need some TLC. Getting involved is step one, step two is shelling out real money for your own test gear, and once you have that... you're sucked in forever. And not just for your machines, it's like the bumper sticker you see on pickup trucks... Yes, this is my pickup truck. No I won't help you move. LOL! Can change that to... Yes, this is my service monitor. No I won't help you tune your duplexer. Haha... of course, reality is... you will. 'Cause you're a good ham... just make 'em bring beer over... and save the beer for AFTER you've done the tuning... -- Nate Duehr, WY0X n...@natetech.com On Mon, 12 Oct 2009 11:04 -0700, Bill Hudson w6...@pacbell.net wrote: After installing some Hustler Spirit HD antennas in snow and ice conditions, and visiting the site to see several inches of radial ice everywhere, I became a dealer for them. They are built after the order to frequency. I ordered a 420 9 dB HD Omni, and a 440 9 dB Omni, and the 420 antenna was physically longer when compared side by side. Makes sense, but it's nice they are not using a one size fits all fiberglass case. I won't have to be worrying about replacing the Spirit Antennas for a long time, while I enjoy good coverage from the antennas. I have a statement that I always share: When you buy quality, it only hurts once. Bill Hudson W6CBS From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Dan Hancock Sent: Monday, October 12, 2009 4:16 AM To: repeater builders Subject: [Repeater-Builder] Re: Antenna question Since no one else has mentioned them I'll say take a look at the Hustler Spirit series antennas. Built similar to Stationmasters without the charging you for the name price. http://www.new-tronics.com/main/html/base_spirit.html Dan N8DJP --- In Repeater-Builder@yahoogroups.com, W3ML w...@... wrote: Now I realize that the DB type antenna is the best, but we do not have 800 bucks to buy one. You can do FAR better than that price. Primus Electronics, Joliet, IL. 800.435.1636. I have no connection with them other than being a very satisfied customer. Laryn K8TVZ
[Repeater-Builder] Re: Antenna question
Thanks everyone for the advice. When we got the antenna it had been up for 10 years or more at 350 feet. The fiberglass on the coil section was practically destroyed and the joints were very loose. We cleaned all the corrosion off the metal, re-fiber-glassed the section to seal it and used no-ox. Then when it was re-assembled, I sprayed it with clear polyurethane and then screwed the sections together to try and tighten them up besides having the hose clamps on them. It still wobbles and I believe there is something wrong inside the fiber-glassed section and that is what is causing some or all the trouble with noise on incoming signals. It is really funny that when the transmitter transmits the controller messages it is perfectly clear and readable, no matter what power level we are at. But, let a user come in we have the repeater set at over 10 watts out of repeater and the noise is horrible. Replacing the antenna would be just another step in trying to figure all this out. Thanks to all for your suggestions. It looks like we may have to wait until the club can come up with the money to buy that DB antenna and just run it a low power. 73 John --- In Repeater-Builder@yahoogroups.com, Jim Cicirello ka2...@... wrote: John, It sounds like you already have a G7? How old is it and how does it operate? I am trying to figure out how it stood up to your WX Elements. My two cents .In WNY on the highest hill in Allegany County I had and still have a G7. I had it up for about seven years at 160' until I got a used stationmaster and used the Repeater-Builder Article to bring it down in frequency to 147 MHz At that point we pulled the G7 put up the Stationmaster and also increased the cable from ½ to 7/8. The G7 was cleaned up and put back on the tower at about 60' for packet. The antenna was side mounted and we used a PVC T and piece of PVC Pipe to stabilize the top from whipping around. I would never top mount one. Also there are two weak points in my opinion, one being the radials. If I ever put up a new G7 I will replace the Radials with solid aluminum, as the hollow stock radials are fragile. The coaxial connector is also fragile. We had a tower crew, put a G7 on a commercial tower and they broke the connector right out of the base installing he pigtail. We sent the next one up with the pig tail installed and weatherproofed on the ground which I recommend. We have another one in G7 in Pa. on top of a radar tower and that has been in service for 12 plus years. My experience has been good as I have been where you are that you have to do with what you can afford. 73 JIM KA2AJH From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of W3ML Sent: Sunday, October 11, 2009 10:09 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Antenna question Hi again, We are looking to replace that used antenna after getting 100 feet of new Andrews 1/2 donated to our club. Now I realize that the DB type antenna is the best, but we do not have 800 bucks to buy one. So, my question is should we just get a new G7-144 to replace the used G7 or is there another type of vertical that we could get that would be good. Being in North Indiana, our winters can be quite brutal, so we would probably want something durable. Any suggestions. 73 John, W3ML
Re: [Repeater-Builder] Re: Antenna question
No, this is VERY typical. The antenna is bad. Chuck WB2EDV - Original Message - From: W3ML w...@arrl.net To: Repeater-Builder@yahoogroups.com Sent: Sunday, October 11, 2009 1:15 PM Subject: [Repeater-Builder] Re: Antenna question It still wobbles and I believe there is something wrong inside the fiber-glassed section and that is what is causing some or all the trouble with noise on incoming signals. It is really funny that when the transmitter transmits the controller messages it is perfectly clear and readable, no matter what power level we are at. But, let a user come in we have the repeater set at over 10 watts out of repeater and the noise is horrible.
Re: [Repeater-Builder] Re: Antenna question
Agreed. This is a classic sign of an antenna that's gone bad, and unless you've got a good isolator with sufficient load you're probably doing bad things to your transmitter... not to mention all the noise you're likely generating for other site users when you're transmitting. Needs to be replaced ASAP. Matthew Kaufman Chuck Kelsey wrote: No, this is VERY typical. The antenna is bad. Chuck WB2EDV - Original Message - From: W3ML w...@arrl.net To: Repeater-Builder@yahoogroups.com Sent: Sunday, October 11, 2009 1:15 PM Subject: [Repeater-Builder] Re: Antenna question It still wobbles and I believe there is something wrong inside the fiber-glassed section and that is what is causing some or all the trouble with noise on incoming signals. It is really funny that when the transmitter transmits the controller messages it is perfectly clear and readable, no matter what power level we are at. But, let a user come in we have the repeater set at over 10 watts out of repeater and the noise is horrible. Yahoo! Groups Links
[Repeater-Builder] Re: Antenna question
That is the conclusion that I have come to as everybody has said that GE Mastr II should not be bad. Thanks and 73 John --- In Repeater-Builder@yahoogroups.com, Matthew Kaufman matt...@... wrote: Agreed. This is a classic sign of an antenna that's gone bad, and unless you've got a good isolator with sufficient load you're probably doing bad things to your transmitter... not to mention all the noise you're likely generating for other site users when you're transmitting. Needs to be replaced ASAP. Matthew Kaufman Chuck Kelsey wrote: No, this is VERY typical. The antenna is bad. Chuck WB2EDV - Original Message - From: W3ML w...@... To: Repeater-Builder@yahoogroups.com Sent: Sunday, October 11, 2009 1:15 PM Subject: [Repeater-Builder] Re: Antenna question It still wobbles and I believe there is something wrong inside the fiber-glassed section and that is what is causing some or all the trouble with noise on incoming signals. It is really funny that when the transmitter transmits the controller messages it is perfectly clear and readable, no matter what power level we are at. But, let a user come in we have the repeater set at over 10 watts out of repeater and the noise is horrible. Yahoo! Groups Links
Re: [Repeater-Builder] Re: Antenna question
At this point, you've got a the smoking gun. It's as good as DNA ;-) Chuck WB2EDV - Original Message - From: W3ML w...@arrl.net To: Repeater-Builder@yahoogroups.com Sent: Sunday, October 11, 2009 2:33 PM Subject: [Repeater-Builder] Re: Antenna question That is the conclusion that I have come to as everybody has said that GE Mastr II should not be bad. Thanks and 73 John --- In Repeater-Builder@yahoogroups.com, Matthew Kaufman matt...@... wrote:
[Repeater-Builder] Re: Antenna question
I Definitely agree, go with a commercial antenna built to perform for may years. Another good omni antenna is the ComTelco XL series antennas. I have several of these up and working very well in both VHF and UHF Ham and commercial. Matthew Kaufman ... wrote: Given that last statement, I suspect that it won't take long for the price of multiple G7-144s (not to mention the costs/time of repeatedly I use Telewave, with their generous amateur radio discount, at all my sites and I've gone over a decade at some with no replacement required (even the antenna that went through a winter tower collapse is still going). Matthew Kaufman
[Repeater-Builder] Re: Antenna question
--- In Repeater-Builder@yahoogroups.com, W3ML w...@... wrote: Now I realize that the DB type antenna is the best, but we do not have 800 bucks to buy one. You can do FAR better than that price. Primus Electronics, Joliet, IL. 800.435.1636. I have no connection with them other than being a very satisfied customer. Laryn K8TVZ
[Repeater-Builder] Re: Antenna question
John, You may want to look into Morad Antennas. They make a 10db 2 Meter antenna that works very well. From www.morad.com VHF-146 10dB High performance 2 meter VHF 10dB gain @ 146 MHz #9114 $593.00 I have had a pair of them up on the Oregon Coast for 20 years with top support and they are still working great. They are 20+ feet in length just like a StationMaster. They were designed for the fishing boats on the Bering sea where ice and wind is almost an everyday event. If you have a good marine dealer in the area the price might be a little less that the advertised list price. Joe - WA7JAW --- In Repeater-Builder@yahoogroups.com, W3ML w...@... wrote: That is the conclusion that I have come to as everybody has said that GE Mastr II should not be bad. Thanks and 73 John --- In Repeater-Builder@yahoogroups.com, Matthew Kaufman matthew@ wrote: Agreed. This is a classic sign of an antenna that's gone bad, and unless you've got a good isolator with sufficient load you're probably doing bad things to your transmitter... not to mention all the noise you're likely generating for other site users when you're transmitting. Needs to be replaced ASAP. Matthew Kaufman Chuck Kelsey wrote: No, this is VERY typical. The antenna is bad. Chuck WB2EDV - Original Message - From: W3ML w3ml@ To: Repeater-Builder@yahoogroups.com Sent: Sunday, October 11, 2009 1:15 PM Subject: [Repeater-Builder] Re: Antenna question It still wobbles and I believe there is something wrong inside the fiber-glassed section and that is what is causing some or all the trouble with noise on incoming signals. It is really funny that when the transmitter transmits the controller messages it is perfectly clear and readable, no matter what power level we are at. But, let a user come in we have the repeater set at over 10 watts out of repeater and the noise is horrible. Yahoo! Groups Links
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Paul Plack wrote: Actually, in theory, a fiberglas-enclosed colinear array fed from one end requires more elements and length to equal the gain of an otherwise comparable colinear array fed at each element. The upper elements of a Stationmaster are seeing less RF current than the ones closer to the feedpoint, which degrades the pattern and gain. Well, the point was that a VHF 4-bay winds up being about 20', and yields about 6 dBd gain. A typical VHF Stationmaster-type colinear array, is about 23' long, and is spec'd at 5.2dBd gain or so. A 10dB gain Stationmaster-type antenna for VHF would be VERY long, and not mechanically stable, which I think you were getting at too. There are 9dB folded dipole arrays made for VHF, ie, and 8-bay. They are about 40' long, but because of that, they are only suitable for side mounting, they need a support at the bottom and in the middle.
RE: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Paul, This length always leads me to telling Hams that the 17 ft Comet does not have the 8+ dbd gain the package says. An antenna 44 ft long to get the 9-10 db gain from a very professional company with years of experience and now someone is going to make same in 17 ft package. Doubling the antenna will give 3 db gain so if got one at 20 ft w/6 db gain and putting a second on at 40 or 44 ft will give 9 db, no problem. It is doable as you noted. Of course the guy with the Comet 8 db 17 ft would think putting on 2 at 34 ft would give 16 db, hi. 73, ron, n9ee/r Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome. On Fri, May 9, 2008 at 10:50 PM, Paul Finch wrote: Do a Google search for yourself, it's the first result that comes up. The DB-228 is the same way, it about 44 feet long overall. Paul ___ From: Repeater-Builder@ yahoogroups. com [mailto:Repeater- [EMAIL PROTECTED] ups.com] On Behalf Of Nate Duehr Sent: Friday, May 09, 2008 12:26 PM To: Repeater-Builder@ yahoogroups. com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Paul Finch wrote: Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. dBi or dBd? Very important. DB is a useless number without that third letter when rating antennas. (GRIN) I'd say generally that what you're describing is not physically possible. (Unless the thing is enormous.) The Sinclair SD-218 is 40' long, and rated at 11.5 dBd and has 8 folded-dipole bays. The antenna is taller than my 2 story house. http://www.sinclair technologies. com/catalog/ product.aspx? id=1693 http://www.sinclairtechnologies.com/catalog/product.aspx?id=1693 (They also work great. Two of them stacked on an 85' tower with a whole whopping 5' of vertical separation -- ha -- makes for one hell of a combined TX / shared RX system for multiple VHF machines at one of our sites.) So... there's no way a Super Stationmaster even comes close. The physics just don't work out. The much more commonly-seen SD-214 is 20' long and is 8.5 dBd. http://www.sinclair technologies. com/catalog/ product.aspx? id=42 http://www.sinclairtechnologies.com/catalog/product.aspx?id=42 Note: You lose 1 dB (dBd) if you get the Heavy-Duty/Low- PIM option. http://www.sinclair technologies. com/catalog/ product.aspx? id=2055 http://www.sinclairtechnologies.com/catalog/product.aspx?id=2055 Nate WY0X http://www.sinclairtechnologies.com/catalog/product.aspx?id=2055 No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.11/1422 - Release Date: 5/8/2008 5:24 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.11/1422 - Release Date: 5/8/2008 5:24 PM
RE: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
At 5/10/2008 04:36, you wrote: Paul, This length always leads me to telling Hams that the 17 ft Comet does not have the 8+ dbd gain the package says. I don't recall the package saying dBd, but their website clearly indicates 8.5 dBi @ 146 MHz. BTW, I measured the gain of the GP9 @ 440 MHz (compared against a known Yagi antenna using multiple far-field signal sources). It is in fact as they claim, around 11.5 dBi. Bob NO6B
RE: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Dang, must have misread something. Was in a hurry, link below Paul HYPERLINK http://www.ke3ht.org/14691/specsheet_220-2n.pdfhttp://www.ke3ht.org/14691/ specsheet_220-2n.pdf _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Laryn Lohman Sent: Friday, May 09, 2008 10:14 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry --- In HYPERLINK mailto:Repeater-Builder%40yahoogroups.com[EMAIL PROTECTED] m, Paul Finch [EMAIL PROTECTED] wrote: Do a Google search for yourself, it's the first result that comes up. The DB-228 is the same way, it about 44 feet long overall. Paul Finch wrote: Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. The first one that comes up in a Google search is UHF at 10dbd. Seems like the earlier posts were discussing fiberglass antennas, which I have yet to see 9dbd in VHF. Maybe I missed something?? Laryn K8TVZ No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.14/1425 - Release Date: 5/9/2008 12:38 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.14/1425 - Release Date: 5/9/2008 12:38 PM
RE: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
By the way, I was admitting I made an error reading the gain. I think I transposed the 9 MHz bandwidth with the gain, my error. Paul _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Paul Finch Sent: Saturday, May 10, 2008 11:00 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Dang, must have misread something. Was in a hurry, link below Paul HYPERLINK http://www.ke3ht.org/14691/specsheet_220-2n.pdfhttp://www.ke3ht.-org/14691 /-specsheet_-220-2n.pdf _ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Laryn Lohman Sent: Friday, May 09, 2008 10:14 PM To: [EMAIL PROTECTED] Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry --- In HYPERLINK mailto:Repeater-Builder%40yahoogroups.com[EMAIL PROTECTED] m, Paul Finch [EMAIL PROTECTED] wrote: Do a Google search for yourself, it's the first result that comes up. The DB-228 is the same way, it about 44 feet long overall. Paul Finch wrote: Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. The first one that comes up in a Google search is UHF at 10dbd. Seems like the earlier posts were discussing fiberglass antennas, which I have yet to see 9dbd in VHF. Maybe I missed something?? Laryn K8TVZ No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.14/1425 - Release Date: 5/9/2008 12:38 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.14/1425 - Release Date: 5/9/2008 12:38 PM No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.14/1425 - Release Date: 5/9/2008 12:38 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.14/1425 - Release Date: 5/9/2008 12:38 PM
[Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
--- In Repeater-Builder@yahoogroups.com, Paul Finch [EMAIL PROTECTED] wrote: By the way, I was admitting I made an error reading the gain. I think I transposed the 9 MHz bandwidth with the gain, my error. Paul I appreciate the admission Paul. I always try to keep an open mind though. I'm finding out that the more I know, the more I know that I don't know... sigh Laryn K8TVZ
Re: RE: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and
Paul, Yep that is the advantage of side mounted antennas, but they can still take a hit. Normally much less of a hit, but can be a problem. Probably most damage done with hits is not the direct hit, but where it goes after. It can hit your antenna and end up in your computer which was not connected to any of the RF gear. I experienced this about a month ago. Direct hit on an antenna that was not connected to anything and the lightning got to my Verizon router/phone/cable system. Took out most of it and the 2 computers connected. Blew the heck out of the antenna. Was all over the yard. With the high currents from lightning high voltages are generated all thru its path and these in the wrong places can jump to other pieces. 73, ron, n9ee/r From: Paul Finch [EMAIL PROTECTED] Date: 2008/05/08 Thu PM 10:26:12 CDT To: Repeater-Builder@yahoogroups.com Subject: RE: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Ron, Remember that lightning not only hits the top of the tower but can come back off the tower and hit something else in it's way, I think I heard in around 150 foot increments. The only hit of lightning that did any damage at my tower was from a direct hit that did no damage to the antennas or feedline. It apparently hit the tower near the top and came back off somewhere lower down the tower and hit the power pole next to the tower. It took out a lightning arrestor in a paging base which in turn opened the circuit breaker the base was on as well as the main breaker. No other damage. Paul From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Ron Wright Sent: Thursday, May 08, 2008 7:03 AM To:Repeater-Builder@yahoogroups.com Subject: Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Joe, I agree the 224 probably handles lightning better than the fiberglass versions. I think the folded dipoles being on a mast and the mast takes most of the hit where with the fiberglass the antenna itself takes it. I would not like to mount a fiberglass antenna on top without a top bracket. I've seen good quality new fiberglass antennas have wind static type noise on new installs due to blowing in the wind. I am sure the swaying over time takes it toll. Of course I like bottom and top mounts on all long antennas, but if top mounted is the install then the DB224 would be preferred. Thanks for you input. 73, ron, n9ee/r From: MCH [EMAIL PROTECTED] Date: 2008/05/07 Wed PM 02:12:33 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry I haven't had as many problems with lightning and the fiberglass antennas as I have with wind causing fractures in the connections between the elements. In the case of the coasts, you have to deal with that AND salt, so I doubt there is any good solution. The above said, I do believe the 224 type antennas do handle lightning better - I didn't mean to imply that they don't. I'm only saying in those I've seen wind is the bigger threat. In the case of a top mounted antenna, there is no way to stabilize the top of the fiberglass antenna. Joe M. Ron Wright wrote: Dick, This discussion of weather proofing an antenna was started in part because I am replacing a 4 bay DB224 up high and near the Gulf of Mexico. We think the salt air got to it. We have had similar problems in the past. The antenna has been up for about 12 years. I was looking for a solution to the salt air. The painting issue came up because of this. I am replacing with a Telewave ANT150F6-2 fiberglass enclosed antenna. However, many have had problems with these and the Celwave or RFS Super Station Master with lightning. They do not handle the lightning as well as the DB224 due to, one reason, some use solder to hold the elements together inside the radome. However, mine is side mounted and hope this will not be a problem. The salt air is. I like the Station Master, but also like the DB224. On VHF one does not get easily 10 db gain out of a RFS Station Master, in fact more like 4.7 db for the 140-150 MHz antenna. The Telewave uses a longer fiberglass radome for its version allowing all the elements to be inserted. The UHF version does have higher gain, 9 db, gain. The folded dipoles allow squewing the pattern easier and more than the station master. About all it will allow is moving around and in/out from the tower. The folded dipoles are much more flexible in this issue. Lots of good responses on this. Know many learned a lot. I did. 73, ron, n9ee/r Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. I've seen them used in small towns with limited
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
--- On Fri, 5/9/08, Laryn Lohman [EMAIL PROTECTED] wrote: From: Laryn Lohman [EMAIL PROTECTED] Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry To: Repeater-Builder@yahoogroups.com Date: Friday, May 9, 2008, 12:09 AM --- In Repeater-Builder@yahoogroups.com, Paul Finch [EMAIL PROTECTED] wrote: Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. Paul Paul, could you please post a link to the above mentioned antenna? It's tough searching; it seems there are dozens and dozens of antennas that have taken that name. Laryn K8TVZ I would like to see that also. It must be about 40 feet long or more. Maybe he was thinking of a UHF antenna or the exposed dipole antenna with all elements on one side. Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
RE: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Any tower over 150 feet tall can get a direct hit on the side. It will not necessarily hit the top of the tower. A side mounted antenna on a tall tower is not a guarantee that it won't be hit directly. If a wire is run outside of a side mounted antenna and connected to the tower above and below the antenna it will shield the antenna from a direct strike. In other words the wire will be hit rather than the antenna. 73 Gary K4FMX _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Paul Finch Sent: Thursday, May 08, 2008 11:26 PM To: Repeater-Builder@yahoogroups.com Subject: RE: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Ron, Remember that lightning not only hits the top of the tower but can come back off the tower and hit something else in it's way, I think I heard in around 150 foot increments. The only hit of lightning that did any damage at my tower was from a direct hit that did no damage to the antennas or feedline. It apparently hit the tower near the top and came back off somewhere lower down the tower and hit the power pole next to the tower. It took out a lightning arrestor in a paging base which in turn opened the circuit breaker the base was on as well as the main breaker. No other damage. Paul _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Ron Wright Sent: Thursday, May 08, 2008 7:03 AM To: Repeater-Builder@yahoogroups.com Subject: Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Joe, I agree the 224 probably handles lightning better than the fiberglass versions. I think the folded dipoles being on a mast and the mast takes most of the hit where with the fiberglass the antenna itself takes it. I would not like to mount a fiberglass antenna on top without a top bracket. I've seen good quality new fiberglass antennas have wind static type noise on new installs due to blowing in the wind. I am sure the swaying over time takes it toll. Of course I like bottom and top mounts on all long antennas, but if top mounted is the install then the DB224 would be preferred. Thanks for you input. 73, ron, n9ee/r From: MCH [EMAIL PROTECTED] mailto:mch%40nb.net Date: 2008/05/07 Wed PM 02:12:33 CDT To: Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry I haven't had as many problems with lightning and the fiberglass antennas as I have with wind causing fractures in the connections between the elements. In the case of the coasts, you have to deal with that AND salt, so I doubt there is any good solution. The above said, I do believe the 224 type antennas do handle lightning better - I didn't mean to imply that they don't. I'm only saying in those I've seen wind is the bigger threat. In the case of a top mounted antenna, there is no way to stabilize the top of the fiberglass antenna. Joe M. Ron Wright wrote: Dick, This discussion of weather proofing an antenna was started in part because I am replacing a 4 bay DB224 up high and near the Gulf of Mexico. We think the salt air got to it. We have had similar problems in the past. The antenna has been up for about 12 years. I was looking for a solution to the salt air. The painting issue came up because of this. I am replacing with a Telewave ANT150F6-2 fiberglass enclosed antenna. However, many have had problems with these and the Celwave or RFS Super Station Master with lightning. They do not handle the lightning as well as the DB224 due to, one reason, some use solder to hold the elements together inside the radome. However, mine is side mounted and hope this will not be a problem. The salt air is. I like the Station Master, but also like the DB224. On VHF one does not get easily 10 db gain out of a RFS Station Master, in fact more like 4.7 db for the 140-150 MHz antenna. The Telewave uses a longer fiberglass radome for its version allowing all the elements to be inserted. The UHF version does have higher gain, 9 db, gain. The folded dipoles allow squewing the pattern easier and more than the station master. About all it will allow is moving around and in/out from the tower. The folded dipoles are much more flexible in this issue. Lots of good responses on this. Know many learned a lot. I did. 73, ron, n9ee/r Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. I've seen them used in small towns with limited coverage Public Safety fleets, and Local Paging, but only where limited range coverage is required. When I worked in Mobile Radio Communications ALL Remote Base / Repeater antennas were stacked coaxial antennas inside
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Paul Finch wrote: Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. dBi or dBd? Very important. DB is a useless number without that third letter when rating antennas. (GRIN) I'd say generally that what you're describing is not physically possible. (Unless the thing is enormous.) The Sinclair SD-218 is 40' long, and rated at 11.5 dBd and has 8 folded-dipole bays. The antenna is taller than my 2 story house. http://www.sinclairtechnologies.com/catalog/product.aspx?id=1693 (They also work great. Two of them stacked on an 85' tower with a whole whopping 5' of vertical separation -- ha -- makes for one hell of a combined TX / shared RX system for multiple VHF machines at one of our sites.) So... there's no way a Super Stationmaster even comes close. The physics just don't work out. The much more commonly-seen SD-214 is 20' long and is 8.5 dBd. http://www.sinclairtechnologies.com/catalog/product.aspx?id=42 Note: You lose 1 dB (dBd) if you get the Heavy-Duty/Low-PIM option. http://www.sinclairtechnologies.com/catalog/product.aspx?id=2055 Nate WY0X
Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Most commercial use real reliable gain figures for their antennas. Like the Ringo-Ranger for Hams it is advertised as 6 db gain and for commercial it is 4.5 db...same antenna, but different catalog, hi. Also where is the gain. Often verticals have gains that are elevated above or below the horizon. Sure have the gain, but not in the location one might want. As Nate said think a Super Station Master that had 9 or more db gain would really be 2 of them, just as the Sinclair SD-218 is 40' long, and rated at 11.5 dBd and has 8 folded-dipole bays is really 2 DB224 antennas connected as one. There are also 2 ele DB224 type antennas with less gain of course. So a Super Station Master that was 40 ft long should have more gain. Same with UHF version. It is longer than 150 version and should have the 9 db gain. 73, ron, n9ee/r From: Nate Duehr [EMAIL PROTECTED] Date: 2008/05/09 Fri PM 12:26:26 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Paul Finch wrote: Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. dBi or dBd? Very important. DB is a useless number without that third letter when rating antennas. (GRIN) I'd say generally that what you're describing is not physically possible. (Unless the thing is enormous.) The Sinclair SD-218 is 40' long, and rated at 11.5 dBd and has 8 folded-dipole bays. The antenna is taller than my 2 story house. http://www.sinclairtechnologies.com/catalog/product.aspx?id=1693 (They also work great. Two of them stacked on an 85' tower with a whole whopping 5' of vertical separation -- ha -- makes for one hell of a combined TX / shared RX system for multiple VHF machines at one of our sites.) So... there's no way a Super Stationmaster even comes close. The physics just don't work out. The much more commonly-seen SD-214 is 20' long and is 8.5 dBd. http://www.sinclairtechnologies.com/catalog/product.aspx?id=42 Note: You lose 1 dB (dBd) if you get the Heavy-Duty/Low-PIM option. http://www.sinclairtechnologies.com/catalog/product.aspx?id=2055 Nate WY0X Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
RE: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Do a Google search for yourself, it's the first result that comes up. The DB-228 is the same way, it about 44 feet long overall. Paul _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Nate Duehr Sent: Friday, May 09, 2008 12:26 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Paul Finch wrote: Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. dBi or dBd? Very important. DB is a useless number without that third letter when rating antennas. (GRIN) I'd say generally that what you're describing is not physically possible. (Unless the thing is enormous.) The Sinclair SD-218 is 40' long, and rated at 11.5 dBd and has 8 folded-dipole bays. The antenna is taller than my 2 story house. HYPERLINK http://www.sinclairtechnologies.com/catalog/product.aspx?id=1693http://www .sinclair-technologies.-com/catalog/-product.aspx?-id=1693 (They also work great. Two of them stacked on an 85' tower with a whole whopping 5' of vertical separation -- ha -- makes for one hell of a combined TX / shared RX system for multiple VHF machines at one of our sites.) So... there's no way a Super Stationmaster even comes close. The physics just don't work out. The much more commonly-seen SD-214 is 20' long and is 8.5 dBd. HYPERLINK http://www.sinclairtechnologies.com/catalog/product.aspx?id=42http://www.s inclair-technologies.-com/catalog/-product.aspx?-id=42 Note: You lose 1 dB (dBd) if you get the Heavy-Duty/Low--PIM option. HYPERLINK http://www.sinclairtechnologies.com/catalog/product.aspx?id=2055http://www .sinclair-technologies.-com/catalog/-product.aspx?-id=2055 Nate WY0X No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.11/1422 - Release Date: 5/8/2008 5:24 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.11/1422 - Release Date: 5/8/2008 5:24 PM
[Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
--- In Repeater-Builder@yahoogroups.com, Paul Finch [EMAIL PROTECTED] wrote: Do a Google search for yourself, it's the first result that comes up. The DB-228 is the same way, it about 44 feet long overall. Paul Finch wrote: Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. The first one that comes up in a Google search is UHF at 10dbd. Seems like the earlier posts were discussing fiberglass antennas, which I have yet to see 9dbd in VHF. Maybe I missed something?? Laryn K8TVZ
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
On May 9, 2008, at 9:13 PM, Laryn Lohman wrote: --- In Repeater-Builder@yahoogroups.com, Paul Finch [EMAIL PROTECTED] wrote: Do a Google search for yourself, it's the first result that comes up. The DB-228 is the same way, it about 44 feet long overall. Paul Finch wrote: Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. The first one that comes up in a Google search is UHF at 10dbd. Seems like the earlier posts were discussing fiberglass antennas, which I have yet to see 9dbd in VHF. Maybe I missed something?? Laryn K8TVZ That's what came up for me also... UHF. Made by someone in Florida, on a web page clearly marked: For Export Only. (Don't ask me why... I don't know.) http://www.wiscointl.com/celwave/antennas/uhf/pd455/index.htm The second one that comes up is Cellwave/RFSWorld's page, which is a great example of an utterly useless web page, if you don't know which model number is the VHF model. http://www.rfsworld.com/index.php?p=354l=1mode=hierarchy But if you back up a page then you can get to their PDF of their print catalog: http://www2.rfsworld.com/RFS_Edition3/pdfs/BSA_Omni_201-204.pdf Which shows the highest gain VHF antenna in their fleet is 5.25 dBd gain, for the model that will cover the ham band, and roughly 19.2' tall. So... 8.5 dBd Sinclair 20' long 4-dipole array 5.25 dBd RFS/Cellwave 20' long fiberglass stick I know which one I would want, even barring all the other reasons for avoiding fiberglass sticks, and assuming no other mounting, budgetary, or aesthetic limitations imposed by the site. -- Nate Duehr, WY0X [EMAIL PROTECTED]
Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Dick, I was really getting into your comments until you recommended Radio Shack as a source for connector sealing material, hi. Yep we are going to get some good stuff for sealing the connectors at 1175 ft AGL. Lightning, from professional studies I've seen, has most of its energy from DC to about 1 MHz and then tapers off at 20 db/decade from there. There is a lot of high freq energy. Well, if one gets a direct lightning hit about any commercial 2-way or less antenna is toast or spinters or...just gone to antenna heaven. The concern by most is indirect hits and protection of equipment. The DC grounding helps some, but also helps with other static noise build up. The antenna installation is well designed for lightning in that it is a FM broadcast station. The feedline I am on is part of the station and they take very seriously lightning protection. The way my system is assembled I have little fear for the equipment on the ground. It is just the way the system is put together. I don't think anyone suggested painting the antenna would help with lightning. The discussion was how to extend the life of an antenna and my interest was for use in heavy salt air. This is the reason for going to a fiberglass enclosed antenna over the exposed dipole type like the DB224. Would prefer the DB224 because of the pattern control, but antenna life is also a major factor. I am going with the Telewave ANT150F6-2. I will get some pattern distortion due to the tower, 7 ft face, but will probably get wider coverage than what I had with DB224. Wider in that the pattern will be more cirmetrical around the tower. Thanks for your comments. 73, ron, n9ee/r ps: I have copies of a hand written 30 page document made from a study by GE in the 70s on lightning protection for 2-way sites. This was done by degreed engineer studying sites with the understanding of how electricity works. Not just a well this worked and this did not, but why this worked or did not. From: Dick [EMAIL PROTECTED] Date: 2008/05/07 Wed PM 11:08:38 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Ron and gang: As Dick W7TIO noted, the antenna should be selected based on the desired coverage range of the rptr. While StationMaster (SM) and similar antennas are at DC ground potential, they're ovbiously not at DC ground for RF frequencies. A lightning strike generally has a fundamental frequency around 125 KHz. The lightning channel's voltage will be in the millions just before the channel ionizes, at which time the channel impedance approaches zero ohms and the flash happens. The current in the flash channel can reach 250,000 amps. The problem is that the lightning discharge also has frequency components that extend well up into and beyond 400 MHz. There's still a lot of energy in those upper frequencies. This energy can, and usuallhy does do a lot of damage to the SM type of antenna. The good news is that the antenna provides some protection for the radio, but other protection is still necessarey, such as lkightning diverters in the coaxial cable and grounded feed-throughs where the cable enters the rptr building. The conductive window (usually a copper plate about 1/8 thick should be well grounded with a piece of lightning rod cable that goes to an 8-foot ground rod. By the way, this should be done regardless of the antenna type. Painting an SM type of antenna will extend its life in the salt air you described, but it won't add any lightning protedtion. You'll also want to cover outdoor coaxial connectors with the self-sealing tape available at Radio Shack and other places that sell such stuff. The tape eventually bonds to itself at the molecular level and provides excellent environmental protection to the connectors so they won't corrode. When you paint the SM type antenna's fiberglass radome, use an epoxy paint that doesn't use metallic powder as the coloring agent. In short, there's not much you can do to prevent lightning damage to an SM-type antenna, but it would help to side mount it on the tower well below the tower top. Mount the antenna so that it's distance from the tower is non-resonant at your operating frequency. Hope this helps. Dick W1NMZ Manager (Retired) Electromagnetic Engineering and Test Lockheed Skunk Works - Original Message - From: Ron Wright To: Repeater-Builder@yahoogroups.com Sent: 07 May, 2008 11:10 Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Dick, This discussion of weather proofing an antenna was started in part because I am replacing a 4 bay DB224 up high and near the Gulf of Mexico. We think the salt air got to it. We have had similar problems in the past. The antenna has been up for about 12 years. I was looking for a solution to the salt air. The painting issue came up because of this. I am
Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Joe, I agree the 224 probably handles lightning better than the fiberglass versions. I think the folded dipoles being on a mast and the mast takes most of the hit where with the fiberglass the antenna itself takes it. I would not like to mount a fiberglass antenna on top without a top bracket. I've seen good quality new fiberglass antennas have wind static type noise on new installs due to blowing in the wind. I am sure the swaying over time takes it toll. Of course I like bottom and top mounts on all long antennas, but if top mounted is the install then the DB224 would be preferred. Thanks for you input. 73, ron, n9ee/r From: MCH [EMAIL PROTECTED] Date: 2008/05/07 Wed PM 02:12:33 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry I haven't had as many problems with lightning and the fiberglass antennas as I have with wind causing fractures in the connections between the elements. In the case of the coasts, you have to deal with that AND salt, so I doubt there is any good solution. The above said, I do believe the 224 type antennas do handle lightning better - I didn't mean to imply that they don't. I'm only saying in those I've seen wind is the bigger threat. In the case of a top mounted antenna, there is no way to stabilize the top of the fiberglass antenna. Joe M. Ron Wright wrote: Dick, This discussion of weather proofing an antenna was started in part because I am replacing a 4 bay DB224 up high and near the Gulf of Mexico. We think the salt air got to it. We have had similar problems in the past. The antenna has been up for about 12 years. I was looking for a solution to the salt air. The painting issue came up because of this. I am replacing with a Telewave ANT150F6-2 fiberglass enclosed antenna. However, many have had problems with these and the Celwave or RFS Super Station Master with lightning. They do not handle the lightning as well as the DB224 due to, one reason, some use solder to hold the elements together inside the radome. However, mine is side mounted and hope this will not be a problem. The salt air is. I like the Station Master, but also like the DB224. On VHF one does not get easily 10 db gain out of a RFS Station Master, in fact more like 4.7 db for the 140-150 MHz antenna. The Telewave uses a longer fiberglass radome for its version allowing all the elements to be inserted. The UHF version does have higher gain, 9 db, gain. The folded dipoles allow squewing the pattern easier and more than the station master. About all it will allow is moving around and in/out from the tower. The folded dipoles are much more flexible in this issue. Lots of good responses on this. Know many learned a lot. I did. 73, ron, n9ee/r Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. I've seen them used in small towns with limited coverage Public Safety fleets, and Local Paging, but only where limited range coverage is required. When I worked in Mobile Radio Communications ALL Remote Base / Repeater antennas were stacked coaxial antennas inside a tapered Fiberglass radome (Station Master type?) and operated at DC ground, with a properly grounded mount, which was realy a good lightning rod as well, where there was never a problem, and at a normally 10 db gain!! There are Internet aricles on building these.. Commercial / Public Safety fleets are normally of defined coverage areas, but we hams want to talk as far as we can... which means more gain, and I've never heard of anyone wanting to paint or preserve an antenna, for everything was enclosed except a link cornor reflector or beam antenna!!! Dick, W7TIO Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome. Yahoo! Groups Links Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
ocwarren2000 wrote: Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. A 4-bay stacked dipole array is 6dB gain. The largest fiberglass coaxial gain antenna made for VHF is about 5-6dB as well. And just about the same size. I've seen them used in small towns with limited coverage Public Safety fleets, and Local Paging, but only where limited range coverage is required. When I worked in Mobile Radio Communications ALL Remote Base / Repeater antennas were stacked coaxial antennas inside a tapered Fiberglass radome (Station Master type?) and operated at DC ground, with a properly grounded mount, which was realy a good lightning rod as well, where there was never a problem, and at a normally 10 db gain!! There are Internet aricles on building these.. 10 dB gain omni fiberglass coaxials are reserved for UHF and above. A 10 dB gain stick for VHF would be over 40' long.
Re: [Repeater-Builder] Re: antenna question
John Transue wrote: I'm afraid there is no easy way to evaluate an antenna except from signal reports. Even if you have a field strength meter, which I do not have, the reading would only be relative except on a calibrated test range. Thanks for sharing your experience with me. John A true Frequency Domain Reflectometer (such as the Anritsu or Bird line) will show whether there is a problem with an antenna or feedline at RF frequencies. Unlike a TDR, which sends a DC pulse down the feedline, an FDR sends pulses at the RF frequency if interest, and will tell if there is a bad spot in the feedline, how far it is up the line, or if it's antenna itself. http://www.us.anritsu.com/products/ARO/North/Eng/Handheld-Cable-and-Antenna-Analyzer---Site-Master.aspx?cat=1cat2=2cat3=24cat4=0 http://www.bird-electronic.com/products/product.aspx?id=500
RE: [Repeater-Builder] Re: antenna question
Wow!! Those instruments are EXPENSIVE. Guess I'll have to rely on signal reports. Or maybe I can find a local service that can test for me. Thanks again. I appreciate the help. John -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of wd8chl Sent: Thursday, May 08, 2008 3:59 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question John Transue wrote: I'm afraid there is no easy way to evaluate an antenna except from signal reports. Even if you have a field strength meter, which I do not have, the reading would only be relative except on a calibrated test range. Thanks for sharing your experience with me. John A true Frequency Domain Reflectometer (such as the Anritsu or Bird line) will show whether there is a problem with an antenna or feedline at RF frequencies. Unlike a TDR, which sends a DC pulse down the feedline, an FDR sends pulses at the RF frequency if interest, and will tell if there is a bad spot in the feedline, how far it is up the line, or if it's antenna itself. http://www.us. http://www.us.anritsu.com/products/ARO/North/Eng/Handheld-Cable-and-Ant enna-Analyzer---Site-Master.aspx?cat=1cat2=2cat3=24cat4=0 anritsu.com/products/ARO/North/Eng/Handheld-Cable-and-Antenna-Analyzer-- -Site-Master.aspx?cat=1cat2=2cat3=24cat4=0 http://www.bird- http://www.bird-electronic.com/products/product.aspx?id=500 electronic.com/products/product.aspx?id=500 __ NOD32 2918 (20080303) Information __ This message was checked by NOD32 antivirus system. http://www.eset.com
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Actually, in theory, a fiberglas-enclosed colinear array fed from one end requires more elements and length to equal the gain of an otherwise comparable colinear array fed at each element. The upper elements of a Stationmaster are seeing less RF current than the ones closer to the feedpoint, which degrades the pattern and gain. A stacked, end-fed colinear can be made longer for increased gain, but only to a certain point without hitting diminishing returns, because of this current distribution issue. In theory, a colinear dipole array fed at each element could add gain by increasing size indefinitely, adding 3 dB gain every time the number of elements doubles, but it, too, eventually reaches a point of diminishing returns due to loss in the coax harnesses. Choose the compromise best-adapted to the application. Paul, AE4KR - Original Message - From: wd8chl To: Repeater-Builder@yahoogroups.com Sent: Thursday, May 08, 2008 1:53 PM Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry ocwarren2000 wrote: Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. A 4-bay stacked dipole array is 6dB gain. The largest fiberglass coaxial gain antenna made for VHF is about 5-6dB as well. And just about the same size. I've seen them used in small towns with limited coverage Public Safety fleets, and Local Paging, but only where limited range coverage is required. When I worked in Mobile Radio Communications ALL Remote Base / Repeater antennas were stacked coaxial antennas inside a tapered Fiberglass radome (Station Master type?) and operated at DC ground, with a properly grounded mount, which was realy a good lightning rod as well, where there was never a problem, and at a normally 10 db gain!! There are Internet aricles on building these.. 10 dB gain omni fiberglass coaxials are reserved for UHF and above. A 10 dB gain stick for VHF would be over 40' long.
RE: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Ron, Remember that lightning not only hits the top of the tower but can come back off the tower and hit something else in it's way, I think I heard in around 150 foot increments. The only hit of lightning that did any damage at my tower was from a direct hit that did no damage to the antennas or feedline. It apparently hit the tower near the top and came back off somewhere lower down the tower and hit the power pole next to the tower. It took out a lightning arrestor in a paging base which in turn opened the circuit breaker the base was on as well as the main breaker. No other damage. Paul _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Ron Wright Sent: Thursday, May 08, 2008 7:03 AM To: Repeater-Builder@yahoogroups.com Subject: Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Joe, I agree the 224 probably handles lightning better than the fiberglass versions. I think the folded dipoles being on a mast and the mast takes most of the hit where with the fiberglass the antenna itself takes it. I would not like to mount a fiberglass antenna on top without a top bracket. I've seen good quality new fiberglass antennas have wind static type noise on new installs due to blowing in the wind. I am sure the swaying over time takes it toll. Of course I like bottom and top mounts on all long antennas, but if top mounted is the install then the DB224 would be preferred. Thanks for you input. 73, ron, n9ee/r From: MCH HYPERLINK mailto:mch%40nb.net[EMAIL PROTECTED] Date: 2008/05/07 Wed PM 02:12:33 CDT To: HYPERLINK mailto:Repeater-Builder%40yahoogroups.com[EMAIL PROTECTED] m Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry I haven't had as many problems with lightning and the fiberglass antennas as I have with wind causing fractures in the connections between the elements. In the case of the coasts, you have to deal with that AND salt, so I doubt there is any good solution. The above said, I do believe the 224 type antennas do handle lightning better - I didn't mean to imply that they don't. I'm only saying in those I've seen wind is the bigger threat. In the case of a top mounted antenna, there is no way to stabilize the top of the fiberglass antenna. Joe M. Ron Wright wrote: Dick, This discussion of weather proofing an antenna was started in part because I am replacing a 4 bay DB224 up high and near the Gulf of Mexico. We think the salt air got to it. We have had similar problems in the past. The antenna has been up for about 12 years. I was looking for a solution to the salt air. The painting issue came up because of this. I am replacing with a Telewave ANT150F6-2 fiberglass enclosed antenna. However, many have had problems with these and the Celwave or RFS Super Station Master with lightning. They do not handle the lightning as well as the DB224 due to, one reason, some use solder to hold the elements together inside the radome. However, mine is side mounted and hope this will not be a problem. The salt air is. I like the Station Master, but also like the DB224. On VHF one does not get easily 10 db gain out of a RFS Station Master, in fact more like 4.7 db for the 140-150 MHz antenna. The Telewave uses a longer fiberglass radome for its version allowing all the elements to be inserted. The UHF version does have higher gain, 9 db, gain. The folded dipoles allow squewing the pattern easier and more than the station master. About all it will allow is moving around and in/out from the tower. The folded dipoles are much more flexible in this issue. Lots of good responses on this. Know many learned a lot. I did. 73, ron, n9ee/r Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. I've seen them used in small towns with limited coverage Public Safety fleets, and Local Paging, but only where limited range coverage is required. When I worked in Mobile Radio Communications ALL Remote Base / Repeater antennas were stacked coaxial antennas inside a tapered Fiberglass radome (Station Master type?) and operated at DC ground, with a properly grounded mount, which was realy a good lightning rod as well, where there was never a problem, and at a normally 10 db gain!! There are Internet aricles on building these.. Commercial / Public Safety fleets are normally of defined coverage areas, but we hams want to talk as far as we can... which means more gain, and I've never heard of anyone wanting to paint or preserve an antenna, for everything was enclosed except a link cornor reflector or beam antenna!!! Dick, W7TIO Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome
RE: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. Paul _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of wd8chl Sent: Thursday, May 08, 2008 2:54 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry ocwarren2000 wrote: Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. A 4-bay stacked dipole array is 6dB gain. The largest fiberglass coaxial gain antenna made for VHF is about 5-6dB as well. And just about the same size. I've seen them used in small towns with limited coverage Public Safety fleets, and Local Paging, but only where limited range coverage is required. When I worked in Mobile Radio Communications ALL Remote Base / Repeater antennas were stacked coaxial antennas inside a tapered Fiberglass radome (Station Master type?) and operated at DC ground, with a properly grounded mount, which was realy a good lightning rod as well, where there was never a problem, and at a normally 10 db gain!! There are Internet aricles on building these.. 10 dB gain omni fiberglass coaxials are reserved for UHF and above. A 10 dB gain stick for VHF would be over 40' long. No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.10/1421 - Release Date: 5/7/2008 5:23 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.11/1422 - Release Date: 5/8/2008 5:24 PM
[Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
--- In Repeater-Builder@yahoogroups.com, Paul Finch [EMAIL PROTECTED] wrote: Actually I looked up the Super Stationmaster and and they have one that's rated at 9 DB at VHF. Paul Paul, could you please post a link to the above mentioned antenna? It's tough searching; it seems there are dozens and dozens of antennas that have taken that name. Laryn K8TVZ
[Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
--- In Repeater-Builder@yahoogroups.com, Bruce Bagwell [EMAIL PROTECTED] wrote: OK guys, along this same line, I have a VHF all copper J-Pole and plan on building UHF all copper J-pole. Is common clear lacquer OK to prevent corrosion on the copper elements? I have used automotive type black silicone under 2 wide electrical tape to seal connections and the coax itself. The Coax to antenna connectors have been soldered to the copper tubing after finding best SWR. Other choices, Clear enamel, colored lacquer/enamel etc. Other stuff I have not even thought of? mainly just stop the copper from turning green but don't want to mess with the antenna in any way. This will be used beside my house and not at some far away repeater. Limited life is OK so long as I am aware of limitations. Bruce KE5TPN This painting of antennas seems to be on many of our minds. Wonder what the antenna manufactures would recommend or what they use if any??? After you get beyond the sales person who swears their products are rock solid and don't need painting or additional protection then you might get someone who would give some info. I would hope they would have done testing for anything they recommend, both SWR and pattern and signal. 73, ron, n9ee/r Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. I've seen them used in small towns with limited coverage Public Safety fleets, and Local Paging, but only where limited range coverage is required. When I worked in Mobile Radio Communications ALL Remote Base / Repeater antennas were stacked coaxial antennas inside a tapered Fiberglass radome (Station Master type?) and operated at DC ground, with a properly grounded mount, which was realy a good lightning rod as well, where there was never a problem, and at a normally 10 db gain!! There are Internet aricles on building these.. Commercial / Public Safety fleets are normally of defined coverage areas, but we hams want to talk as far as we can... which means more gain, and I've never heard of anyone wanting to paint or preserve an antenna, for everything was enclosed except a link cornor reflector or beam antenna!!! Dick, W7TIO From: Chuck Kelsey [EMAIL PROTECTED] Date: 2008/05/04 Sun AM 08:52:31 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon Funny you should mention Krylon... although I haven't done so in recent years, I used to Krylon (clear) all antennas and never had a problem. I forgot all about that until your mention of it. And they were mostly UHF antennas - beams and folded dipoles. Go figure. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 9:44 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
RE: [Repeater-Builder] Re: antenna question
Paul, Using a 5,000 volt power supply sounds like a pretty drastic approach. Does it just boil out the water or blow a hole in the feed line? And if there is no noticeable reaction, the feed line could still be lossy, right? I'm afraid there is no easy way to evaluate an antenna except from signal reports. Even if you have a field strength meter, which I do not have, the reading would only be relative except on a calibrated test range. Thanks for sharing your experience with me. John -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Paul Finch Sent: Saturday, May 03, 2008 11:31 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: antenna question John, By all means it can, I have seen a good dummy load DB224 antenna several times. It had fairly good reflected reading but like I said, it resembled a dummy load more than an antenna. These problems can be addressed. There can be water in the coax harness or straight out corrosion on the connections. You can check the antenna several ways. I have used a signal generator and a spectrum analyzer and do simple loss test to each dipole with a sniffer antenna. I have a friend that checks his harnesses with the dipoles disconnected with a small 5,000 VDC power supply, any water in the coax shows up really well that way. A really high range VOM and check the resistance will work pretty good also but the 5K VDC seems to ferret out all problems. So far, with the ScotchKote I have not had a problem. I have a DB408 that I am taking to Dayton that I got from my ex-boss when they closed the shop that had one coat of Scotchkote that was looks kind of thin. Before I take it to Dayton I will tighten all connections, check it and slop several coats of Scotchkote on it. I normally slop on at least three coats of the stuff, it's messy but I believe in it. So far I have not found anything better in the Texas sun. Paul _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of John Transue Sent: Saturday, May 03, 2008 8:52 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: antenna question So how do you know your antenna is not performing as it should? When an antenna has a corrosion problem, can it still have good VSWR? I think it can. A resistor can have good VSWR. So what should I do to find out whether I need a new antenna? I'd like to benefit from your experience. Thanks for any advice you can give me. John AF4PD -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of georgiaskywarn Sent: Saturday, May 03, 2008 9:15 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: antenna question Well I thought the same thing. I have a db408 that I have treated with plastic dip AND liquid tape. Long story but have several layers (about 3 or 4) of this stuff on there. Each layer I allowed to dry before putting on the next. In the pictures you can see that every joint (metal to metal) is protected by this stuff. I also went up the dipoles far enough for any possible egress of moisture. Might not be pretty, but think it will work. The pics are taken with the antenna temporarily on the side of my tower (not hooked up yet). http://f1.grp. http://f1.grp.yahoofs.com/v1/0GEcSFgRqZpJVmTlqpB72pv8w7tAZtRcCcnp5vmv6q Vr44p8O-ZFzec_HaY2Ga6TgV2Yj_3lzSUfcMnhJ3JGc57pcJsE-k5gcErJ/pix/IMG_1277. JPG yahoofs.com/v1/0GEcSFgRqZpJVmTlqpB72pv8w7tAZtRcCcnp5vmv6qVr44p8O-ZFzec_H aY2Ga6TgV2Yj_3lzSUfcMnhJ3JGc57pcJsE-k5gcErJ/pix/IMG_1277.JPG http://f1.grp. http://f1.grp.yahoofs.com/v1/0GEcSHs2jQFJVmTl6X_XYxKmmCUXuduBzeXqkRzKHC 6GBZz7otBoFOgQDzYeQt3Umjq9dbwHhiGcSIrqsKi9wt2JEamLwVt1E_-7/pix/IMG_1278. JPG yahoofs.com/v1/0GEcSHs2jQFJVmTl6X_XYxKmmCUXuduBzeXqkRzKHC6GBZz7otBoFOgQD zYeQt3Umjq9dbwHhiGcSIrqsKi9wt2JEamLwVt1E_-7/pix/IMG_1278.JPG (remember, you might have to copy and paste it) This antenna has the bracing that wraps around the pipe, not the hose clamp style dipoles. So I drilled through the metal straps and into the pipe. After that I riveted each strap into the pipe. Waiting for my contractor to get the go ahead from the county to replace a Diamond UHF antenna. 73, Robert KD4YDC --- In Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com, Craig [EMAIL PROTECTED] wrote: Paul and others: Other than using Scotchkote has anyone used DIP-IT which is that plastic coating sold in cans designed for dipping tools into to build up a rubber coating on them. Like the scotchkote you would probably have to put sveral coats on, but since it's a rubber base it may last longer than the Scotchkote which harderns. Craig --- In Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com, Paul Finch dpaulfinch@ wrote: Ron, ... The second part of making a new DB folded dipole antenna last
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Dick, This discussion of weather proofing an antenna was started in part because I am replacing a 4 bay DB224 up high and near the Gulf of Mexico. We think the salt air got to it. We have had similar problems in the past. The antenna has been up for about 12 years. I was looking for a solution to the salt air. The painting issue came up because of this. I am replacing with a Telewave ANT150F6-2 fiberglass enclosed antenna. However, many have had problems with these and the Celwave or RFS Super Station Master with lightning. They do not handle the lightning as well as the DB224 due to, one reason, some use solder to hold the elements together inside the radome. However, mine is side mounted and hope this will not be a problem. The salt air is. I like the Station Master, but also like the DB224. On VHF one does not get easily 10 db gain out of a RFS Station Master, in fact more like 4.7 db for the 140-150 MHz antenna. The Telewave uses a longer fiberglass radome for its version allowing all the elements to be inserted. The UHF version does have higher gain, 9 db, gain. The folded dipoles allow squewing the pattern easier and more than the station master. About all it will allow is moving around and in/out from the tower. The folded dipoles are much more flexible in this issue. Lots of good responses on this. Know many learned a lot. I did. 73, ron, n9ee/r Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. I've seen them used in small towns with limited coverage Public Safety fleets, and Local Paging, but only where limited range coverage is required. When I worked in Mobile Radio Communications ALL Remote Base / Repeater antennas were stacked coaxial antennas inside a tapered Fiberglass radome (Station Master type?) and operated at DC ground, with a properly grounded mount, which was realy a good lightning rod as well, where there was never a problem, and at a normally 10 db gain!! There are Internet aricles on building these.. Commercial / Public Safety fleets are normally of defined coverage areas, but we hams want to talk as far as we can... which means more gain, and I've never heard of anyone wanting to paint or preserve an antenna, for everything was enclosed except a link cornor reflector or beam antenna!!! Dick, W7TIO Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
I haven't had as many problems with lightning and the fiberglass antennas as I have with wind causing fractures in the connections between the elements. In the case of the coasts, you have to deal with that AND salt, so I doubt there is any good solution. The above said, I do believe the 224 type antennas do handle lightning better - I didn't mean to imply that they don't. I'm only saying in those I've seen wind is the bigger threat. In the case of a top mounted antenna, there is no way to stabilize the top of the fiberglass antenna. Joe M. Ron Wright wrote: Dick, This discussion of weather proofing an antenna was started in part because I am replacing a 4 bay DB224 up high and near the Gulf of Mexico. We think the salt air got to it. We have had similar problems in the past. The antenna has been up for about 12 years. I was looking for a solution to the salt air. The painting issue came up because of this. I am replacing with a Telewave ANT150F6-2 fiberglass enclosed antenna. However, many have had problems with these and the Celwave or RFS Super Station Master with lightning. They do not handle the lightning as well as the DB224 due to, one reason, some use solder to hold the elements together inside the radome. However, mine is side mounted and hope this will not be a problem. The salt air is. I like the Station Master, but also like the DB224. On VHF one does not get easily 10 db gain out of a RFS Station Master, in fact more like 4.7 db for the 140-150 MHz antenna. The Telewave uses a longer fiberglass radome for its version allowing all the elements to be inserted. The UHF version does have higher gain, 9 db, gain. The folded dipoles allow squewing the pattern easier and more than the station master. About all it will allow is moving around and in/out from the tower. The folded dipoles are much more flexible in this issue. Lots of good responses on this. Know many learned a lot. I did. 73, ron, n9ee/r Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. I've seen them used in small towns with limited coverage Public Safety fleets, and Local Paging, but only where limited range coverage is required. When I worked in Mobile Radio Communications ALL Remote Base / Repeater antennas were stacked coaxial antennas inside a tapered Fiberglass radome (Station Master type?) and operated at DC ground, with a properly grounded mount, which was realy a good lightning rod as well, where there was never a problem, and at a normally 10 db gain!! There are Internet aricles on building these.. Commercial / Public Safety fleets are normally of defined coverage areas, but we hams want to talk as far as we can... which means more gain, and I've never heard of anyone wanting to paint or preserve an antenna, for everything was enclosed except a link cornor reflector or beam antenna!!! Dick, W7TIO Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome. Yahoo! Groups Links
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
Ron and gang: As Dick W7TIO noted, the antenna should be selected based on the desired coverage range of the rptr. While StationMaster (SM) and similar antennas are at DC ground potential, they're ovbiously not at DC ground for RF frequencies. A lightning strike generally has a fundamental frequency around 125 KHz. The lightning channel's voltage will be in the millions just before the channel ionizes, at which time the channel impedance approaches zero ohms and the flash happens. The current in the flash channel can reach 250,000 amps. The problem is that the lightning discharge also has frequency components that extend well up into and beyond 400 MHz. There's still a lot of energy in those upper frequencies. This energy can, and usuallhy does do a lot of damage to the SM type of antenna. The good news is that the antenna provides some protection for the radio, but other protection is still necessarey, such as lkightning diverters in the coaxial cable and grounded feed-throughs where the cable enters the rptr building. The conductive window (usually a copper plate about 1/8 thick should be well grounded with a piece of lightning rod cable that goes to an 8-foot ground rod. By the way, this should be done regardless of the antenna type. Painting an SM type of antenna will extend its life in the salt air you described, but it won't add any lightning protedtion. You'll also want to cover outdoor coaxial connectors with the self-sealing tape available at Radio Shack and other places that sell such stuff. The tape eventually bonds to itself at the molecular level and provides excellent environmental protection to the connectors so they won't corrode. When you paint the SM type antenna's fiberglass radome, use an epoxy paint that doesn't use metallic powder as the coloring agent. In short, there's not much you can do to prevent lightning damage to an SM-type antenna, but it would help to side mount it on the tower well below the tower top. Mount the antenna so that it's distance from the tower is non-resonant at your operating frequency. Hope this helps. Dick W1NMZ Manager (Retired) Electromagnetic Engineering and Test Lockheed Skunk Works - Original Message - From: Ron Wright To: Repeater-Builder@yahoogroups.com Sent: 07 May, 2008 11:10 Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry Dick, This discussion of weather proofing an antenna was started in part because I am replacing a 4 bay DB224 up high and near the Gulf of Mexico. We think the salt air got to it. We have had similar problems in the past. The antenna has been up for about 12 years. I was looking for a solution to the salt air. The painting issue came up because of this. I am replacing with a Telewave ANT150F6-2 fiberglass enclosed antenna. However, many have had problems with these and the Celwave or RFS Super Station Master with lightning. They do not handle the lightning as well as the DB224 due to, one reason, some use solder to hold the elements together inside the radome. However, mine is side mounted and hope this will not be a problem. The salt air is. I like the Station Master, but also like the DB224. On VHF one does not get easily 10 db gain out of a RFS Station Master, in fact more like 4.7 db for the 140-150 MHz antenna. The Telewave uses a longer fiberglass radome for its version allowing all the elements to be inserted. The UHF version does have higher gain, 9 db, gain. The folded dipoles allow squewing the pattern easier and more than the station master. About all it will allow is moving around and in/out from the tower. The folded dipoles are much more flexible in this issue. Lots of good responses on this. Know many learned a lot. I did. 73, ron, n9ee/r Er.. uh... Excuse me, but why all this commotion about painting and preserving antennas??? If everyone used limited range, low gain, stacked folded dipoles, then maybe so, but stacked folded dipoles are a low gain limited range item. I've seen them used in small towns with limited coverage Public Safety fleets, and Local Paging, but only where limited range coverage is required. When I worked in Mobile Radio Communications ALL Remote Base / Repeater antennas were stacked coaxial antennas inside a tapered Fiberglass radome (Station Master type?) and operated at DC ground, with a properly grounded mount, which was realy a good lightning rod as well, where there was never a problem, and at a normally 10 db gain!! There are Internet aricles on building these.. Commercial / Public Safety fleets are normally of defined coverage areas, but we hams want to talk as far as we can... which means more gain, and I've never heard of anyone wanting to paint or preserve an antenna, for everything was enclosed except a link cornor reflector or beam antenna!!! Dick, W7TIO Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all
[Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Yhis reminds me of the story of the two hams driving a guy wire stake with a sledge hammer. The one holding the stake said When I nod my head, Hit It Dail N6dgt --- In Repeater-Builder@yahoogroups.com, Paul Plack [EMAIL PROTECTED] wrote: Uh...Burt, I think he meant water in a separate cup. Faked me out at first, too! - Original Message - From: Burt Lang To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 1:58 PM Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Fine except for one problem. Water is an excellant absorber of the microwaves used in the microwave ovens (2.45 GHz) So your water will heat up quickly irregardless of the coating. The only substances that are better absorbers of that frequency are animal or vegetable fats because they contain 9 times the molecular bonds (the O-H bond) that actually do the absorbing. Burt VE2BMQ (who used to be a professional chemist) IM Ashford wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - *From:* skipp025 mailto:[EMAIL PROTECTED] *To:* Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com *Sent:* Sunday, May 04, 2008 2:44 PM *Subject:* [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey wb2edv@ wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 skipp025@ To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC
Re: Re: Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Hello All A couple of years ago I needed to camoflodge several new fiberglass antennas. I investigated spray can paints at the local home store and came up with Rustolum's specialty Paint For Plastic---that's what it says in headline form on the can and it also says Direct--To--Plastic--Paint and also that it is intended for indor/outdoor applications. I bought a couple of cans and tested it for RF loss problems by heavily spraying a large thin plastic bag which, after drying I put alone in the microwavenot the slightest warming after a one minute run---No problem at 2400 Mhz, plenty good for VHF/UHF. I scrubed the antennas top to bottom with acetone and painted. The paint covered very well, is still in place and the antennas work just fine. Scott, N6NXI
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
So what color(s) did you use to camouflage them? Joe M. Scott Overstreet wrote: Hello All A couple of years ago I needed to camoflodge several new fiberglass antennas. I investigated spray can paints at the local home store and came up with Rustolum's specialty Paint For Plastic---that's what it says in headline form on the can and it also says Direct--To--Plastic--Paint and also that it is intended for indor/outdoor applications. I bought a couple of cans and tested it for RF loss problems by heavily spraying a large thin plastic bag which, after drying I put alone in the microwavenot the slightest warming after a one minute run---No problem at 2400 Mhz, plenty good for VHF/UHF. I scrubed the antennas top to bottom with acetone and painted. The paint covered very well, is still in place and the antennas work just fine. Scott, N6NXI No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1414 - Release Date: 5/4/2008 12:31 PM
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Lite and dark green purposely splotchy. - Original Message - From: MCH To: Repeater-Builder@yahoogroups.com Sent: Monday, May 05, 2008 11:20 AM Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote So what color(s) did you use to camouflage them? Joe M. Scott Overstreet wrote: Hello All A couple of years ago I needed to camoflodge several new fiberglass antennas. I investigated spray can paints at the local home store and came up with Rustolum's specialty Paint For Plastic---that's what it says in headline form on the can and it also says Direct--To--Plastic--Paint and also that it is intended for indor/outdoor applications. I bought a couple of cans and tested it for RF loss problems by heavily spraying a large thin plastic bag which, after drying I put alone in the microwavenot the slightest warming after a one minute run---No problem at 2400 Mhz, plenty good for VHF/UHF. I scrubed the antennas top to bottom with acetone and painted. The paint covered very well, is still in place and the antennas work just fine. Scott, N6NXI -- No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1414 - Release Date: 5/4/2008 12:31 PM
RE: [Repeater-Builder] Re: antenna question
Nitto make a very good roll of malable self sealing rubber tape which works very well and is moderately priced . To: Repeater-Builder@yahoogroups.com From: [EMAIL PROTECTED] Date: Sat, 3 May 2008 21:54:05 + Subject: [Repeater-Builder] Re: antenna question You don't have to use Scotchkote... it's just easy to find, well known and well trusted as a solution sealer. Dip-it breaks down pretty fast and I'm sure the sun would probably beat it up pretty bad. There are other sealers that work well... but Scotchkote is the most practical answer for most of the common projects where it fits well. cheers, s. Craig [EMAIL PROTECTED] wrote: Paul and others: Other than using Scotchkote has anyone used DIP-IT which is that plastic coating sold in cans designed for dipping tools into to build up a rubber coating on them. Like the scotchkote you would probably have to put sveral coats on, but since it's a rubber base it may last longer than the Scotchkote which harderns. Craig --- In Repeater-Builder@yahoogroups.com, Paul Finch dpaulfinch@ wrote: Ron, ... The second part of making a new DB folded dipole antenna last is sealing every nook and cranny of the antenna with 3M Scotchkote. I paint at least two coats on every screwhead, coax end, nut, plastic molded junction and anything that could be a point of bimetal corrosion or coax water leak. If I could dip it in Scotchkote I would. ... _ Never miss another e-mail with Hotmail on your mobile. http://www.livelife.ninemsn.com.au/article.aspx?id=343869
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn [EMAIL PROTECTED] wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC
Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Coating, painting, etc of antenna elements has always been in question. Some don't like using insulated wire for HF dipoles although think this has long been resolved and is no problem. I am sure depends on the insulation. I would think a substance that is ok for joints would be ok for the antenna elements, but since dealing with different thing here still is of concern. Wonder if anyone has made a fiberglass radom for something like the DB224. Would be big if wanted to allow the full arrangement of the elements, but good idea. 73, ron, n9ee/r From: Chuck Kelsey [EMAIL PROTECTED] Date: 2008/05/04 Sun AM 06:53:49 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn [EMAIL PROTECTED] wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
For what it is worth, I believe Telewave makes a folded dipole with an epoxy coating for protection. The difference is that it was designed for the coating. Chuck WB2EDV - Original Message - From: Ron Wright [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 8:09 AM Subject: Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Coating, painting, etc of antenna elements has always been in question. Some don't like using insulated wire for HF dipoles although think this has long been resolved and is no problem. I am sure depends on the insulation. I would think a substance that is ok for joints would be ok for the antenna elements, but since dealing with different thing here still is of concern. Wonder if anyone has made a fiberglass radom for something like the DB224. Would be big if wanted to allow the full arrangement of the elements, but good idea. 73, ron, n9ee/r
[Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon
Funny you should mention Krylon... although I haven't done so in recent years, I used to Krylon (clear) all antennas and never had a problem. I forgot all about that until your mention of it. And they were mostly UHF antennas - beams and folded dipoles. Go figure. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 9:44 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s.
RE: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon
I wonder how a good grade of Polyurethane spray or brush on would work? Paul -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Chuck Kelsey Sent: Sunday, May 04, 2008 8:53 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon Funny you should mention Krylon... although I haven't done so in recent years, I used to Krylon (clear) all antennas and never had a problem. I forgot all about that until your mention of it. And they were mostly UHF antennas - beams and folded dipoles. Go figure. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 9:44 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Yahoo! Groups Links No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1413 - Release Date: 5/3/2008 11:22 AM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1413 - Release Date: 5/3/2008 11:22 AM Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon
I'm sure the chemical composition of Krylon and equivalent Spray Paints have changed quite a bit since 1974. Because of Government Air Quality Management here in California I have a hard time getting any type of serious paint over the counter. Most all of it is or was considered serious air pollution and of course it is or was. Many Californians do notice the impact of not so great air when we visit some of the other States around the US. Go out of the USA to a third world country (air quality wise) and it's sometimes hard not to gag or cough. Doesn't stop most of us from traveling but it does make us appreciate the apparent overzellous efforts of our State Government. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Funny you should mention Krylon... although I haven't done so in recent years, I used to Krylon (clear) all antennas and never had a problem. I forgot all about that until your mention of it. And they were mostly UHF antennas - beams and folded dipoles. Go figure. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 9:44 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s.
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 2:44 PM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC
[Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
The only fly in the soup is... I would suspect compound properties at ~2450MHz have different D-Factor performance versus the mentioned in the VHF band. cheers, s. IM Ashford [EMAIL PROTECTED] wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 2:44 PM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey wb2edv@ wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 skipp025@ To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
The problem with high loss tangent is that you'd never see it as reflected power. You could lose 3 dB or more never know it. Bob NO6B At 5/4/2008 04:53, you wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 mailto:skipp025%40yahoo.com[EMAIL PROTECTED] To: mailto:Repeater-Builder%40yahoogroups.comRepeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn [EMAIL PROTECTED] wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon
I painted a refurbished, retuned UHF StationMaster with white Krylon spray paint. Checked VSWR signal strengths before after: no change. Bob NO6B At 5/4/2008 06:52, you wrote: Funny you should mention Krylon... although I haven't done so in recent years, I used to Krylon (clear) all antennas and never had a problem. I forgot all about that until your mention of it. And they were mostly UHF antennas - beams and folded dipoles. Go figure. Chuck WB2EDV - Original Message - From: skipp025 mailto:skipp025%40yahoo.com[EMAIL PROTECTED] To: mailto:Repeater-Builder%40yahoogroups.comRepeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 9:44 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s.
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
At 5/4/2008 07:44, you wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE This is an excellent suggestion. I have 2 sets of ceramic plates in the cupboard: plates from one set get so hot in the microwave I think they get hotter than the food on them, the others stay at room temperature. It's possible that some materials may still have low loss @ 50 or 146 MHz, but have high loss at 2.45 GHz (where the microwave oven's magnetron tube operates), so you may get some false positives with this test, but if it passes it's definitely a good material. Bob NO6B
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon
Skip, The last time I was in Ontario, CA, about 50 miles east of LA, much of the time we could not see a 5000 ft mountain 2 miles away. Was there with fellow engineer and he was looking for something to take a picture of so he could show his wife. We told him about the mountain and he had not noticed it. We had been there about 3 days, hi. One could tell when there was a 3 day weekend...on Monday morning the air was clear due to lower, not low, traffic on I-10 I think. I hope things have improved. However, most all the places I've lived east of the Mississippi we never had this problem, but I have never lived in cities like Chicago or NY. Do live in Tampa, FL, hi. 73, ron, n9ee/r From: skipp025 [EMAIL PROTECTED] Date: 2008/05/04 Sun AM 09:25:20 CDT To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon I'm sure the chemical composition of Krylon and equivalent Spray Paints have changed quite a bit since 1974. Because of Government Air Quality Management here in California I have a hard time getting any type of serious paint over the counter. Most all of it is or was considered serious air pollution and of course it is or was. Many Californians do notice the impact of not so great air when we visit some of the other States around the US. Go out of the USA to a third world country (air quality wise) and it's sometimes hard not to gag or cough. Doesn't stop most of us from traveling but it does make us appreciate the apparent overzellous efforts of our State Government. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Funny you should mention Krylon... although I haven't done so in recent years, I used to Krylon (clear) all antennas and never had a problem. I forgot all about that until your mention of it. And they were mostly UHF antennas - beams and folded dipoles. Go figure. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 9:44 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry
This painting of antennas seems to be on many of our minds. Wonder what the antenna manufactures would recommend or what they use if any??? After you get beyond the sales person who swears their products are rock solid and don't need painting or additional protection then you might get someone who would give some info. I would hope they would have done testing for anything they recommend, both SWR and pattern and signal. 73, ron, n9ee/r From: Chuck Kelsey [EMAIL PROTECTED] Date: 2008/05/04 Sun AM 08:52:31 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon Funny you should mention Krylon... although I haven't done so in recent years, I used to Krylon (clear) all antennas and never had a problem. I forgot all about that until your mention of it. And they were mostly UHF antennas - beams and folded dipoles. Go figure. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 9:44 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
Re: Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and
Found this with google search 10/05/1998 Last updated on 20-Dec-2001 How to paint RFS / Celwave antenna radomes to match the surrounding environment, while assuring good electrical performance Written by Radio Frequency Systems RFS receives requests for advice about refinishing weathered antenna radomes or changing the radome color for aesthetic reasons such as camouflage. Any paint selection should be compatible with radome materials and not interfere with the antenna's electrical performance. We do not take a position on any particular manufacturer's paint. However, there are two primary considerations regarding the choice of paint. The first one is adhesion. A variety of radome materials are used for antenna construction so the surface texture will vary. Some paints having the best durability here may be dangerous to work with and require an EPA qualified application facility. Preparation is important. All surface contamination must be removed. The second one is the choice of pigment. RF transparency is crucial, so conductive coloring materials such as carbonblack, lead, and metallic powders cannot be used. Lighter colors are preferred where practicable to reduce internal temperature extremes which could occur on hot, sunny days. There are also some precautions one should take. Mask all connectors and all labels before painting. Maintain all DC ground paths during application. Do not seal any drain or ventilation holes with paint.. We encourage you to contact our Applications Engineering for advice in these matters. However, there is no substitute for detailed instructions and mix ratios provided by the paint manufacturer. RADOME MATERIAL (Standard Color) CELWAVE / RFS PRODUCT LINE 1. Spun Epoxy Fiberglass (Blue) Penetrator Antennas (AxR, BxR Series) 2. Polyester Impregnated Fiberglass (White) Stationmaster Antennas (PDxx Omni Series.) 3. Polyester Impregnated Fiberglass (Grey)FR CELlite Panel Antennas (AP18, 19 Series) 4. ASA (Grey) FR CELlite Panel Antennas (AP90 Series) 5. AES/ABS (White or Grey) US Panel Antennas (Other APxx Models) 6. Gel Coated Fiberglass Tubing (White) Marine Antennas (Cel-1,3 etc.) 7. Teflon Coated Fiberglass [Field Painting Not Possible]Planar Radomes for Shrouded Microwave Antennas 8. Hypalon [Painting Optional]Planar Radomes for Shrouded Microwave Antennas Was at this RFS Site: http://www.rfsworld.com/index.php?p=276l=1listName=applicationnotesindexVal=1 From: Ron Wright [EMAIL PROTECTED] Date: 2008/05/04 Sun PM 02:30:13 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Kry This painting of antennas seems to be on many of our minds. Wonder what the antenna manufactures would recommend or what they use if any??? After you get beyond the sales person who swears their products are rock solid and don't need painting or additional protection then you might get someone who would give some info. I would hope they would have done testing for anything they recommend, both SWR and pattern and signal. 73, ron, n9ee/r From: Chuck Kelsey [EMAIL PROTECTED] Date: 2008/05/04 Sun AM 08:52:31 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon Funny you should mention Krylon... although I haven't done so in recent years, I used to Krylon (clear) all antennas and never had a problem. I forgot all about that until your mention of it. And they were mostly UHF antennas - beams and folded dipoles. Go figure. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 9:44 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome. Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Fine except for one problem. Water is an excellant absorber of the microwaves used in the microwave ovens (2.45 GHz) So your water will heat up quickly irregardless of the coating. The only substances that are better absorbers of that frequency are animal or vegetable fats because they contain 9 times the molecular bonds (the O-H bond) that actually do the absorbing. Burt VE2BMQ (who used to be a professional chemist) IM Ashford wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - *From:* skipp025 mailto:[EMAIL PROTECTED] *To:* Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com *Sent:* Sunday, May 04, 2008 2:44 PM *Subject:* [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC
RE: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Ian, I would put the dummy load water in a separate cup because the water will heat the cup giving you a false positive. Paul _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of IM Ashford Sent: Sunday, May 04, 2008 9:44 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - From: HYPERLINK mailto:[EMAIL PROTECTED]skipp025 To: HYPERLINK mailto:Repeater-Builder@yahoogroups.comRepeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 2:44 PM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: HYPERLINK mailto:Repeater-Builder%40yahoogroups.com[EMAIL PROTECTED] m Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1413 - Release Date: 5/3/2008 11:22 AM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1413 - Release Date: 5/3/2008 11:22 AM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1413 - Release Date: 5/3/2008 11:22 AM
RE: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
But if it passed at 2.4 GHz it would probably be great for VHF. Paul -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of skipp025 Sent: Sunday, May 04, 2008 10:05 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote The only fly in the soup is... I would suspect compound properties at ~2450MHz have different D-Factor performance versus the mentioned in the VHF band. cheers, s. IM Ashford [EMAIL PROTECTED] wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 2:44 PM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey wb2edv@ wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 skipp025@ To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC Yahoo! Groups Links No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1413 - Release Date: 5/3/2008 11:22 AM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1413 - Release Date: 5/3/2008 11:22 AM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1413 - Release Date: 5/3/2008 11:22 AM Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
You don't care if the cup of water heats up - you are looking to see if the painted cup heats up. The water is only there to prevent burning out the microwave. Joe M. Burt Lang wrote: Fine except for one problem. Water is an excellant absorber of the microwaves used in the microwave ovens (2.45 GHz) So your water will heat up quickly irregardless of the coating. The only substances that are better absorbers of that frequency are animal or vegetable fats because they contain 9 times the molecular bonds (the O-H bond) that actually do the absorbing. Burt VE2BMQ (who used to be a professional chemist) IM Ashford wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - *From:* skipp025 mailto:[EMAIL PROTECTED] *To:* Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com *Sent:* Sunday, May 04, 2008 2:44 PM *Subject:* [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC Yahoo! Groups Links
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Think about it. If you expect the water to act as a heatsink, it would require the cup to transfer heat thru its material. Heat can go both ways and you will never know if heat generated on the outside is heating the water or vice versa, the water is passing thru the cup to the outside. Put a coffee cup of water into your microwave and see how hot the outside of the cup gets when the water is heated. Even if you use a foam cup to isolate the outside from the inside and are using the water to provide a load on the magnatron (which it doesn't need), there will be enough moisture in the foam for it to heat up and probably melt leaving a real mess to cleanup. Burt MCH wrote: You don't care if the cup of water heats up - you are looking to see if the painted cup heats up. The water is only there to prevent burning out the microwave. Joe M. Burt Lang wrote: Fine except for one problem. Water is an excellant absorber of the microwaves used in the microwave ovens (2.45 GHz) So your water will heat up quickly irregardless of the coating. The only substances that are better absorbers of that frequency are animal or vegetable fats because they contain 9 times the molecular bonds (the O-H bond) that actually do the absorbing. Burt VE2BMQ (who used to be a professional chemist) IM Ashford wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - *From:* skipp025 mailto:[EMAIL PROTECTED] *To:* Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com *Sent:* Sunday, May 04, 2008 2:44 PM *Subject:* [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC Yahoo! Groups Links Yahoo! Groups Links
Re: Re: Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
hi all, I've been looking at the Telewave ANT150F6-2, 144-151 MHz fiberglass collinear antenna for Ham repeater at 1175 ft above ground. I think Telewave's version of the Super Station Master. Spec sheet at http://www.telewave.com/pdf/TWDS-7020.pdf The spec says it is 6 db gain and it is 256 (21.33 ft)long. The various ANT150F6 family are for 138-174 and the fiberglass radoms are longer for the 138-151 MHz versions leading me to believe they do not remove elements to fit in one radom. I am also looking at the Telewave TS1546 crossband coupler for 131-174/450-512 MHz, 150 W/port. What you think? On the crossband coupler is an outside enclosure needed meaning, if not, one would just seal the 3 connectors and mount to the tower? 73, ron, n9ee/r Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Mite try a trial run. Put say 4 oz of water in the microwave with nothing else and see how hot it gets. Then do test with water and paint sample. Water will get warmer first run if paint gets warm. The test should be done with same starting temp water so get two 4 oz water samples at same time. See how complicated we can make it, hi. The water in the same container as the paint is on is a notable factor. Do water and paint in separate containers. 73, ron, n9ee/r From: Burt Lang [EMAIL PROTECTED] Date: 2008/05/04 Sun PM 04:53:41 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Think about it. If you expect the water to act as a heatsink, it would require the cup to transfer heat thru its material. Heat can go both ways and you will never know if heat generated on the outside is heating the water or vice versa, the water is passing thru the cup to the outside. Put a coffee cup of water into your microwave and see how hot the outside of the cup gets when the water is heated. Even if you use a foam cup to isolate the outside from the inside and are using the water to provide a load on the magnatron (which it doesn't need), there will be enough moisture in the foam for it to heat up and probably melt leaving a real mess to cleanup. Burt MCH wrote: You don't care if the cup of water heats up - you are looking to see if the painted cup heats up. The water is only there to prevent burning out the microwave. Joe M. Burt Lang wrote: Fine except for one problem. Water is an excellant absorber of the microwaves used in the microwave ovens (2.45 GHz) So your water will heat up quickly irregardless of the coating. The only substances that are better absorbers of that frequency are animal or vegetable fats because they contain 9 times the molecular bonds (the O-H bond) that actually do the absorbing. Burt VE2BMQ (who used to be a professional chemist) IM Ashford wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - *From:* skipp025 mailto:[EMAIL PROTECTED] *To:* Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com *Sent:* Sunday, May 04, 2008 2:44 PM *Subject:* [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC Yahoo! Groups Links Yahoo! Groups Links Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
[Repeater-Builder] Re: antenna question
Also looking at Telewave's NAT150D6-9 4 bay folded dipoles. Specs at: http://www.telewave.com/pdf/TWDS-7045.pdf Looks like Telewave coats the elements and advertises exceptional protection from all kinds of things including salt spray. One question is the mounting. The mounting mast is customer-supplied and think it can be mounted on tower legs. Think each dipole has adjustable arm for spacing. 73, ron, n9ee/r From: Ron Wright [EMAIL PROTECTED] Date: 2008/05/04 Sun PM 04:55:40 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: Re: Re: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote hi all, I've been looking at the Telewave ANT150F6-2, 144-151 MHz fiberglass collinear antenna for Ham repeater at 1175 ft above ground. I think Telewave's version of the Super Station Master. Spec sheet at http://www.telewave.com/pdf/TWDS-7020.pdf The spec says it is 6 db gain and it is 256 (21.33 ft)long. The various ANT150F6 family are for 138-174 and the fiberglass radoms are longer for the 138-151 MHz versions leading me to believe they do not remove elements to fit in one radom. I am also looking at the Telewave TS1546 crossband coupler for 131-174/450-512 MHz, 150 W/port. What you think? On the crossband coupler is an outside enclosure needed meaning, if not, one would just seal the 3 connectors and mount to the tower? 73, ron, n9ee/r Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome. Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Sorry Joe, I misunderstood the original procedure. I can see the purpose of the water now although I still don't believe that an empty oven will burn out easily. If that was true, most of the ovens in the country would now be dead because most everyone is guilty of turning on one with little or nothing in it. Burt MCH wrote: You don't care if the cup of water heats up - you are looking to see if the painted cup heats up. The water is only there to prevent burning out the microwave. Joe M. Burt Lang wrote: Fine except for one problem. Water is an excellant absorber of the microwaves used in the microwave ovens (2.45 GHz) So your water will heat up quickly irregardless of the coating. The only substances that are better absorbers of that frequency are animal or vegetable fats because they contain 9 times the molecular bonds (the O-H bond) that actually do the absorbing. Burt VE2BMQ (who used to be a professional chemist) IM Ashford wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - *From:* skipp025 mailto:[EMAIL PROTECTED] *To:* Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com *Sent:* Sunday, May 04, 2008 2:44 PM *Subject:* [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Also keep in mind the application. On a repeater antenna, 3 dB could be a deal-breaker. On a link, it might be well worth the tradeoff. Resistive losses also lower Q, which increases SWR bandwidth. If you have a remote base, there may be times when introducing a little loss to gain bandwidth might even be desireable. The military, where efficiency is not a design requirement, has taken this to extremes at times. One WWII-era broadband HF whip used on Army vehicles was an 8-foot whip on a 1 kW dummy resistor. Extremely crude, but it worked! 73, Paul, AE4KR - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 10:29 AM Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote The problem with high loss tangent is that you'd never see it as reflected power. You could lose 3 dB or more never know it. Bob NO6B At 5/4/2008 04:53, you wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 mailto:skipp025%40yahoo.com[EMAIL PROTECTED] To: mailto:Repeater-Builder%40yahoogroups.comRepeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn [EMAIL PROTECTED] wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Uh...Burt, I think he meant water in a separate cup. Faked me out at first, too! - Original Message - From: Burt Lang To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 1:58 PM Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Fine except for one problem. Water is an excellant absorber of the microwaves used in the microwave ovens (2.45 GHz) So your water will heat up quickly irregardless of the coating. The only substances that are better absorbers of that frequency are animal or vegetable fats because they contain 9 times the molecular bonds (the O-H bond) that actually do the absorbing. Burt VE2BMQ (who used to be a professional chemist) IM Ashford wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - *From:* skipp025 mailto:[EMAIL PROTECTED] *To:* Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com *Sent:* Sunday, May 04, 2008 2:44 PM *Subject:* [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. Hi all. Here in Yakima Washington, I have supplied Hams with pcs. of corean (counter top material) to use as an insulator in their antenna projects. We have done the same test in the microwave. It stays cool and has lasted years in the direct sunlight. Rod kc7vqr
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
At 5/4/2008 12:58, you wrote: Fine except for one problem. Water is an excellant absorber of the microwaves used in the microwave ovens (2.45 GHz) So your water will heat up quickly irregardless of the coating. Yes, but the idea is that the cup of water (load to keep the magnetron happy) is separate from the poly cup used to test the material. Bob NO6B
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon
This topic reminds me, a friend said he painted his copper J Pole, and it never worked after that. The type of paint, and other factors determine what is and what is not safe to use on an antenna. The only thing I have done is used a tad of NoAlox in joints on antennas. Years ago, I did cover the base of the connector on a Ringo antenna with some Silicone sealer. I don't know if it was from that or something else, but when I moved the antenna later, I was never able to get it to work right again. Now I am leery about using items on antennas that were not made for such types of items. I do have some sealing kits to use on my Heliax connectors, but the kits are from Andrew, and consist of a sealer similar to the coax seal, and some plastic tape that goes over that. The only other thing I have used has been a bit of silicone grease in some spots, and always taped exposed coax connectors with at least two layers of tape. YMMV Wayne WA2YNE On Sun, 04 May 2008 08:52:31 -0500, Chuck Kelsey [EMAIL PROTECTED] wrote: Funny you should mention Krylon... although I haven't done so in recent years, I used to Krylon (clear) all antennas and never had a problem. I forgot all about that until your mention of it. And they were mostly UHF antennas - beams and folded dipoles. Go figure. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 9:44 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. -- Using Opera's revolutionary e-mail client: http://www.opera.com/mail/ Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
No need to be sorry. As for not operating it without a 'load', I would prefer to not take the chance. Think of it as cheap insurance. I'm sure a lot of people have put metal in them, too, but that too is not a good idea. Joe M. Burt Lang wrote: Sorry Joe, I misunderstood the original procedure. I can see the purpose of the water now although I still don't believe that an empty oven will burn out easily. If that was true, most of the ovens in the country would now be dead because most everyone is guilty of turning on one with little or nothing in it. Burt MCH wrote: You don't care if the cup of water heats up - you are looking to see if the painted cup heats up. The water is only there to prevent burning out the microwave. Joe M. Burt Lang wrote: Fine except for one problem. Water is an excellant absorber of the microwaves used in the microwave ovens (2.45 GHz) So your water will heat up quickly irregardless of the coating. The only substances that are better absorbers of that frequency are animal or vegetable fats because they contain 9 times the molecular bonds (the O-H bond) that actually do the absorbing. Burt VE2BMQ (who used to be a professional chemist) IM Ashford wrote: Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - *From:* skipp025 mailto:[EMAIL PROTECTED] *To:* Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com *Sent:* Sunday, May 04, 2008 2:44 PM *Subject:* [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links
[Repeater-Builder] Re: antenna question
Well I thought the same thing. I have a db408 that I have treated with plastic dip AND liquid tape. Long story but have several layers (about 3 or 4) of this stuff on there. Each layer I allowed to dry before putting on the next. In the pictures you can see that every joint (metal to metal) is protected by this stuff. I also went up the dipoles far enough for any possible egress of moisture. Might not be pretty, but think it will work. The pics are taken with the antenna temporarily on the side of my tower (not hooked up yet). http://f1.grp.yahoofs.com/v1/0GEcSFgRqZpJVmTlqpB72pv8w7tAZtRcCcnp5vmv6qVr44p8O-ZFzec_HaY2Ga6TgV2Yj_3lzSUfcMnhJ3JGc57pcJsE-k5gcErJ/pix/IMG_1277.JPG http://f1.grp.yahoofs.com/v1/0GEcSHs2jQFJVmTl6X_XYxKmmCUXuduBzeXqkRzKHC6GBZz7otBoFOgQDzYeQt3Umjq9dbwHhiGcSIrqsKi9wt2JEamLwVt1E_-7/pix/IMG_1278.JPG (remember, you might have to copy and paste it) This antenna has the bracing that wraps around the pipe, not the hose clamp style dipoles. So I drilled through the metal straps and into the pipe. After that I riveted each strap into the pipe. Waiting for my contractor to get the go ahead from the county to replace a Diamond UHF antenna. 73, Robert KD4YDC --- In Repeater-Builder@yahoogroups.com, Craig [EMAIL PROTECTED] wrote: Paul and others: Other than using Scotchkote has anyone used DIP-IT which is that plastic coating sold in cans designed for dipping tools into to build up a rubber coating on them. Like the scotchkote you would probably have to put sveral coats on, but since it's a rubber base it may last longer than the Scotchkote which harderns. Craig --- In Repeater-Builder@yahoogroups.com, Paul Finch dpaulfinch@ wrote: Ron, ... The second part of making a new DB folded dipole antenna last is sealing every nook and cranny of the antenna with 3M Scotchkote. I paint at least two coats on every screwhead, coax end, nut, plastic molded junction and anything that could be a point of bimetal corrosion or coax water leak. If I could dip it in Scotchkote I would. ...
RE: [Repeater-Builder] Re: antenna question
So how do you know your antenna is not performing as it should? When an antenna has a corrosion problem, can it still have good VSWR? I think it can. A resistor can have good VSWR. So what should I do to find out whether I need a new antenna? I'd like to benefit from your experience. Thanks for any advice you can give me. John AF4PD -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of georgiaskywarn Sent: Saturday, May 03, 2008 9:15 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: antenna question Well I thought the same thing. I have a db408 that I have treated with plastic dip AND liquid tape. Long story but have several layers (about 3 or 4) of this stuff on there. Each layer I allowed to dry before putting on the next. In the pictures you can see that every joint (metal to metal) is protected by this stuff. I also went up the dipoles far enough for any possible egress of moisture. Might not be pretty, but think it will work. The pics are taken with the antenna temporarily on the side of my tower (not hooked up yet). http://f1.grp. http://f1.grp.yahoofs.com/v1/0GEcSFgRqZpJVmTlqpB72pv8w7tAZtRcCcnp5vmv6q Vr44p8O-ZFzec_HaY2Ga6TgV2Yj_3lzSUfcMnhJ3JGc57pcJsE-k5gcErJ/pix/IMG_1277. JPG yahoofs.com/v1/0GEcSFgRqZpJVmTlqpB72pv8w7tAZtRcCcnp5vmv6qVr44p8O-ZFzec_H aY2Ga6TgV2Yj_3lzSUfcMnhJ3JGc57pcJsE-k5gcErJ/pix/IMG_1277.JPG http://f1.grp. http://f1.grp.yahoofs.com/v1/0GEcSHs2jQFJVmTl6X_XYxKmmCUXuduBzeXqkRzKHC 6GBZz7otBoFOgQDzYeQt3Umjq9dbwHhiGcSIrqsKi9wt2JEamLwVt1E_-7/pix/IMG_1278. JPG yahoofs.com/v1/0GEcSHs2jQFJVmTl6X_XYxKmmCUXuduBzeXqkRzKHC6GBZz7otBoFOgQD zYeQt3Umjq9dbwHhiGcSIrqsKi9wt2JEamLwVt1E_-7/pix/IMG_1278.JPG (remember, you might have to copy and paste it) This antenna has the bracing that wraps around the pipe, not the hose clamp style dipoles. So I drilled through the metal straps and into the pipe. After that I riveted each strap into the pipe. Waiting for my contractor to get the go ahead from the county to replace a Diamond UHF antenna. 73, Robert KD4YDC --- In Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com, Craig [EMAIL PROTECTED] wrote: Paul and others: Other than using Scotchkote has anyone used DIP-IT which is that plastic coating sold in cans designed for dipping tools into to build up a rubber coating on them. Like the scotchkote you would probably have to put sveral coats on, but since it's a rubber base it may last longer than the Scotchkote which harderns. Craig --- In Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com, Paul Finch dpaulfinch@ wrote: Ron, ... The second part of making a new DB folded dipole antenna last is sealing every nook and cranny of the antenna with 3M Scotchkote. I paint at least two coats on every screwhead, coax end, nut, plastic molded junction and anything that could be a point of bimetal corrosion or coax water leak. If I could dip it in Scotchkote I would. ... __ NOD32 2918 (20080303) Information __ This message was checked by NOD32 antivirus system. http://www.eset.com
RE: [Repeater-Builder] Re: antenna question
John, By all means it can, I have seen a good dummy load DB224 antenna several times. It had fairly good reflected reading but like I said, it resembled a dummy load more than an antenna. These problems can be addressed. There can be water in the coax harness or straight out corrosion on the connections. You can check the antenna several ways. I have used a signal generator and a spectrum analyzer and do simple loss test to each dipole with a sniffer antenna. I have a friend that checks his harnesses with the dipoles disconnected with a small 5,000 VDC power supply, any water in the coax shows up really well that way. A really high range VOM and check the resistance will work pretty good also but the 5K VDC seems to ferret out all problems. So far, with the ScotchKote I have not had a problem. I have a DB408 that I am taking to Dayton that I got from my ex-boss when they closed the shop that had one coat of Scotchkote that was looks kind of thin. Before I take it to Dayton I will tighten all connections, check it and slop several coats of Scotchkote on it. I normally slop on at least three coats of the stuff, it's messy but I believe in it. So far I have not found anything better in the Texas sun. Paul _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of John Transue Sent: Saturday, May 03, 2008 8:52 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: antenna question So how do you know your antenna is not performing as it should? When an antenna has a corrosion problem, can it still have good VSWR? I think it can. A resistor can have good VSWR. So what should I do to find out whether I need a new antenna? I’d like to benefit from your experience. Thanks for any advice you can give me. John AF4PD -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of georgiaskywarn Sent: Saturday, May 03, 2008 9:15 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: antenna question Well I thought the same thing. I have a db408 that I have treated with plastic dip AND liquid tape. Long story but have several layers (about 3 or 4) of this stuff on there. Each layer I allowed to dry before putting on the next. In the pictures you can see that every joint (metal to metal) is protected by this stuff. I also went up the dipoles far enough for any possible egress of moisture. Might not be pretty, but think it will work. The pics are taken with the antenna temporarily on the side of my tower (not hooked up yet). HYPERLINK http://f1.grp.yahoofs.com/v1/0GEcSFgRqZpJVmTlqpB72pv8w7tAZtRcCcnp5vmv6qVr44 p8O-ZFzec_HaY2Ga6TgV2Yj_3lzSUfcMnhJ3JGc57pcJsE-k5gcErJ/pix/IMG_1277.JPGhttp ://f1.grp.-yahoofs.com/-v1/0GEcSFgRqZpJV-mTlqpB72pv8w7tAZ-tRcCcnp5vmv6qVr4-4 p8O-ZFzec_-HaY2Ga6TgV2Yj_-3lzSUfcMnhJ3JGc5-7pcJsE-k5gcErJ/-pix/IMG_1277.-JPG HYPERLINK http://f1.grp.yahoofs.com/v1/0GEcSHs2jQFJVmTl6X_XYxKmmCUXuduBzeXqkRzKHC6GBZ z7otBoFOgQDzYeQt3Umjq9dbwHhiGcSIrqsKi9wt2JEamLwVt1E_-7/pix/IMG_1278.JPGhttp ://f1.grp.-yahoofs.com/-v1/0GEcSHs2jQFJV-mTl6X_XYxKmmCUXu-duBzeXqkRzKHC6GB-Z z7otBoFOgQDzYeQ-t3Umjq9dbwHhiGcS-IrqsKi9wt2JEamLw-Vt1E_-7/pix/-IMG_1278.-JPG (remember, you might have to copy and paste it) This antenna has the bracing that wraps around the pipe, not the hose clamp style dipoles. So I drilled through the metal straps and into the pipe. After that I riveted each strap into the pipe. Waiting for my contractor to get the go ahead from the county to replace a Diamond UHF antenna. 73, Robert KD4YDC --- In HYPERLINK mailto:Repeater-Builder%40yahoogroups.com[EMAIL PROTECTED] m, Craig [EMAIL PROTECTED] wrote: Paul and others: Other than using Scotchkote has anyone used DIP-IT which is that plastic coating sold in cans designed for dipping tools into to build up a rubber coating on them. Like the scotchkote you would probably have to put sveral coats on, but since it's a rubber base it may last longer than the Scotchkote which harderns. Craig --- In HYPERLINK mailto:Repeater-Builder%40yahoogroups.com[EMAIL PROTECTED] m, Paul Finch [EMAIL PROTECTED] wrote: Ron, ... The second part of making a new DB folded dipole antenna last is sealing every nook and cranny of the antenna with 3M Scotchkote. I paint at least two coats on every screwhead, coax end, nut, plastic molded junction and anything that could be a point of bimetal corrosion or coax water leak. If I could dip it in Scotchkote I would. ... __ NOD32 2918 (20080303) Information __ This message was checked by NOD32 antivirus system. HYPERLINK http://www.eset.comhttp://www.eset.com No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1412 - Release Date: 5/2/2008 4:34 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.8/1412 - Release Date: 5/2/2008 4:34 PM
[Repeater-Builder] Re: antenna question
You don't have to use Scotchkote... it's just easy to find, well known and well trusted as a solution sealer. Dip-it breaks down pretty fast and I'm sure the sun would probably beat it up pretty bad. There are other sealers that work well... but Scotchkote is the most practical answer for most of the common projects where it fits well. cheers, s. Craig [EMAIL PROTECTED] wrote: Paul and others: Other than using Scotchkote has anyone used DIP-IT which is that plastic coating sold in cans designed for dipping tools into to build up a rubber coating on them. Like the scotchkote you would probably have to put sveral coats on, but since it's a rubber base it may last longer than the Scotchkote which harderns. Craig --- In Repeater-Builder@yahoogroups.com, Paul Finch dpaulfinch@ wrote: Ron, ... The second part of making a new DB folded dipole antenna last is sealing every nook and cranny of the antenna with 3M Scotchkote. I paint at least two coats on every screwhead, coax end, nut, plastic molded junction and anything that could be a point of bimetal corrosion or coax water leak. If I could dip it in Scotchkote I would. ...
[Repeater-Builder] Re: antenna question
Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC --- In Repeater-Builder@yahoogroups.com, skipp025 [EMAIL PROTECTED] wrote: You don't have to use Scotchkote... it's just easy to find, well known and well trusted as a solution sealer. Dip-it breaks down pretty fast and I'm sure the sun would probably beat it up pretty bad. There are other sealers that work well... but Scotchkote is the most practical answer for most of the common projects where it fits well. cheers, s. Craig kec@ wrote: Paul and others: Other than using Scotchkote has anyone used DIP-IT which is that plastic coating sold in cans designed for dipping tools into to build up a rubber coating on them. Like the scotchkote you would probably have to put sveral coats on, but since it's a rubber base it may last longer than the Scotchkote which harderns. Craig --- In Repeater-Builder@yahoogroups.com, Paul Finch dpaulfinch@ wrote: Ron, ... The second part of making a new DB folded dipole antenna last is sealing every nook and cranny of the antenna with 3M Scotchkote. I paint at least two coats on every screwhead, coax end, nut, plastic molded junction and anything that could be a point of bimetal corrosion or coax water leak. If I could dip it in Scotchkote I would. ...
[Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn [EMAIL PROTECTED] wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC skipp025 skipp025@ wrote: You don't have to use Scotchkote... it's just easy to find, well known and well trusted as a solution sealer. Dip-it breaks down pretty fast and I'm sure the sun would probably beat it up pretty bad. There are other sealers that work well... but Scotchkote is the most practical answer for most of the common projects where it fits well. cheers, s. Craig kec@ wrote: Paul and others: Other than using Scotchkote has anyone used DIP-IT which is that plastic coating sold in cans designed for dipping tools into to build up a rubber coating on them. Like the scotchkote you would probably have to put sveral coats on, but since it's a rubber base it may last longer than the Scotchkote which harderns. Craig --- In Repeater-Builder@yahoogroups.com, Paul Finch dpaulfinch@ wrote: Ron, ... The second part of making a new DB folded dipole antenna last is sealing every nook and cranny of the antenna with 3M Scotchkote. I paint at least two coats on every screwhead, coax end, nut, plastic molded junction and anything that could be a point of bimetal corrosion or coax water leak. If I could dip it in Scotchkote I would. ...
[Repeater-Builder] Re: antenna question
Paul and others: Other than using Scotchkote has anyone used DIP-IT which is that plastic coating sold in cans designed for dipping tools into to build up a rubber coating on them. Like the scotchkote you would probably have to put sveral coats on, but since it's a rubber base it may last longer than the Scotchkote which harderns. Craig --- In Repeater-Builder@yahoogroups.com, Paul Finch [EMAIL PROTECTED] wrote: Ron, ... The second part of making a new DB folded dipole antenna last is sealing every nook and cranny of the antenna with 3M Scotchkote. I paint at least two coats on every screwhead, coax end, nut, plastic molded junction and anything that could be a point of bimetal corrosion or coax water leak. If I could dip it in Scotchkote I would. ...
[Repeater-Builder] Re: Antenna question for the forum.
One of the problems with the multi-band antennas is the available bandwidth, which may not be enough within the frequency range where your repeater normally operates. The Dual Band Hustler Antenna I swept didn't do well in the lower range of the 440-450 band. Their mono banders are pretty nice units... The multi-band Diamond/Comet Antennas are also fairly narrow in available bandwidth. There doesn't seem to be any way to adjust the Fcenter of a multi band antenna. If you have reflected power because the antenna doesn't match well... it's going to try and go somewhere... and that somewhere might not be a good place. Stay away from LMR-400 coax. I've had enough problems with it to easily say it's potential trainwreck. cheers, s. Dan Cation [EMAIL PROTECTED] wrote: While I have not used either of those exact antennas, I have used the Hustler G7 and one of the Diamond Dual Band antennas. We had the Hustler G7 up at 190 feet on a 2 meter repeater on a Cement Plant for nearly 20 years with no problem, other than damage one time due to a lightning strike - we had to replace one of the coils and the top radiator section. The G6 is similar construction to the G7 but quite a bit smaller. The Diamond I have had experience with is quite a bit lighter and does have the protected connector, which I like, but I doubt if it would have stood up to our use at the cement plant. I'd opt for the G6. Just make sure you use dielectric grease on all the joints, make sure they are all tight, and seal it good before you put it up. On the LMR400 issue - the cost is certainly attractive and I know at least one radio dealer here using it on low power commercial and Public Safety repeaters without any problems (according to the dealer). If you already have the coax and don't mind replacing it if you have problems, You might it a try - but keep in mind that you might have to replace it if you have any problems with noise, IMD, or desense. You might get lucky. If you are only running 40 or 50 feet on 150 MHz, you aren't gaining much loss over standard RG8 style coax. 1/2 hardline would be the best choice - you might find a shop that has that much as a cut off or that has been taken out of service somewhere if you look around. 73 and good luck WB0SHN Dan --- In Repeater-Builder@yahoogroups.com, w2sxk w2sxk@ wrote: Goodafternoon, Me and a friend are putting up a secondary VHF repeater and have a antenna question. Being we are on a budget but have looked at these 2 antennas as options. Diamond F22A monoband base or the Husler G6-144B Any pros or cons to these antennas and which would you choose or you have another option? Antenna will be mounted between 30-40' on multiuse rohn 45 tower fed with LMR-400 and subjected to typical Northeast USA weather North of NYC. Ofcourse if money wasn't an issue, I would prompt for a more durible antenna specifically suited for repeater use. We need to keep antenna size down to less then 10' in length and cost down as well. My choice was the Diamond F22A. It apears similiar in size and construction to the X-200 dual band and I have not had any issues with my current intallation. Any comments or suggestions??? 73, Steve - W2SXK w2sxk@
