Re: [Repeater-Builder] Antenna question
On Sun, 11 Oct 2009, Jacob Suter wrote: I thought the prefered poor-man's repeater antenna was a J-pole? Single folded dipole IMO. Out of curiosity - are the 'square dipole' (or 'gapped loop' or whatever they want to call them) antennas usable for repeater use? Example: http://www.hamuniverse.com/loop.htm Add an 'l' on the end of that. I've seen a 'hamsexy' Explorer around these parts (East Texas) with a stack of these on the roof at various frequencies. I personally dislike vertical antennas on cars (at best they generate wind noise, at worst they hit things and get bent/broken) these look like a decent option for truck/SUV use, assuming the other side is hpol too or you're willing to put up with the x-pol losses. It's horizontal-only and you've just found one of the few operators who probably works CW or SSB mobile. M-squared makes several bands of these. -- Kris Kirby, KE4AHR Disinformation Analyst
RE: [Repeater-Builder] Antenna question
Buy a commercial one and cry once. Failing to have the funds you may want to build a colinear out of coax sections. It don't get much cheaper than that. http://www.repeater-builder.com/antenna/wa6svt.html tom [Original Message] From: W3ML w...@arrl.net To: Repeater-Builder@yahoogroups.com Date: 10/11/2009 10:09:31 AM 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 Yahoo! Groups Links
Re: [Repeater-Builder] Antenna question
W3ML wrote: 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. 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 going to the site and climbing the tower to replace them) to equal $800. 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
RE: [Repeater-Builder] Antenna question
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] Antenna question
John, My suggestion is simple: Find the money to buy a decent antenna. Unless your time has no value, your gasoline is free, and you enjoy tower climbing, don't mess with cheap antennas. The great majority of available funds should go into the antenna, feedline, and outdoor mounting hardware- the things that are costly to buy, difficult to install, and the most likely to break during bad weather when it may be dangerous or impossible to get to the site to make repairs. Are you planning to support the Heliax with standoff cushion clamps made of stainless steel, or were you planning to just tie-wrap it to the tower legs? At $20 or so each, just the Heliax supports become a high-cost item when you install one every 3 or 4 feet. The indoor stuff like the repeater and duplexer can be upgraded over time, in the relative comfort and safety of the equipment shelter. Moreover, IMHO, it is not prudent to spend big bucks on the radio and duplexer up front, and then skimp on stuff that goes on the tower. The Hustler G7-144 is really too flimsy to have in repeater service where it is exposed to high winds and temperature extremes. I assembled a G7-144 antenna for my radio club's base station, and I took pains to use Penetrox on all aluminum joints and silicone sealant or Scotch-Kote on dissimilar-material joints. Despite these precautions, water leaked into the base and caused severe corrosion. It's practically junk now. If your repeater site is at one side of the desired coverage area, you might look into offset-pattern dipole antennas, Yagis, or corner reflectors. It makes no sense to put an omni antenna in service where all of the potential users are in one sector. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of W3ML Sent: Sunday, October 11, 2009 7:09 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 Andrew 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] Antenna question
On Sun, 11 Oct 2009, Thomas Oliver wrote: Buy a commercial one and cry once. What he said. Give until it hurts, but a DB-224 or a Super Stationmaster with upper brace are a necessity in environments where ice damage is a possible. Do it once, do it right. Or do it every week/month/year. Are you paying for a tower climber? Failing to have the funds you may want to build a colinear out of coax sections. It don't get much cheaper than that. http://www.repeater-builder.com/antenna/wa6svt.html Wait until that develops a crackle... -- Kris Kirby, KE4AHR Disinformation Analyst
Re: [Repeater-Builder] Antenna question
Kris Kirby wrote: On Sun, 11 Oct 2009, Thomas Oliver wrote: Buy a commercial one and cry once. What he said. Give until it hurts, but a DB-224 or a Super Stationmaster with upper brace are a necessity in environments where ice damage is a possible. Do it once, do it right. Or do it every week/month/year. Are you paying for a tower climber? Failing to have the funds you may want to build a colinear out of coax sections. It don't get much cheaper than that. http://www.repeater-builder.com/antenna/wa6svt.html http://www.repeater-builder.com/antenna/wa6svt.html Wait until that develops a crackle... -- Kris Kirby, KE4AHR Disinformation Analyst I thought the prefered poor-man's repeater antenna was a J-pole? Out of curiosity - are the 'square dipole' (or 'gapped loop' or whatever they want to call them) antennas usable for repeater use? Example: http://www.hamuniverse.com/loop.htm I've seen a 'hamsexy' Explorer around these parts (East Texas) with a stack of these on the roof at various frequencies. I personally dislike vertical antennas on cars (at best they generate wind noise, at worst they hit things and get bent/broken) these look like a decent option for truck/SUV use, assuming the other side is hpol too or you're willing to put up with the x-pol losses. JS
RE: [Repeater-Builder] Antenna question
Have a G7-144 on our ARMY MARS repeater here and has been up since 1998 with no antenna issues. We removed the clamps and drilled holes after tuning the antenna to our frequency and used sheet metal screws to secure the tubing. The antenna is mounted on the top of a building about 180 ft. David -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Eric Lemmon Sent: Sunday, October 11, 2009 11:45 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Antenna question John, My suggestion is simple: Find the money to buy a decent antenna. Unless your time has no value, your gasoline is free, and you enjoy tower climbing, don't mess with cheap antennas. The great majority of available funds should go into the antenna, feedline, and outdoor mounting hardware- the things that are costly to buy, difficult to install, and the most likely to break during bad weather when it may be dangerous or impossible to get to the site to make repairs. Are you planning to support the Heliax with standoff cushion clamps made of stainless steel, or were you planning to just tie-wrap it to the tower legs? At $20 or so each, just the Heliax supports become a high-cost item when you install one every 3 or 4 feet. The indoor stuff like the repeater and duplexer can be upgraded over time, in the relative comfort and safety of the equipment shelter. Moreover, IMHO, it is not prudent to spend big bucks on the radio and duplexer up front, and then skimp on stuff that goes on the tower. The Hustler G7-144 is really too flimsy to have in repeater service where it is exposed to high winds and temperature extremes. I assembled a G7-144 antenna for my radio club's base station, and I took pains to use Penetrox on all aluminum joints and silicone sealant or Scotch-Kote on dissimilar-material joints. Despite these precautions, water leaked into the base and caused severe corrosion. It's practically junk now. If your repeater site is at one side of the desired coverage area, you might look into offset-pattern dipole antennas, Yagis, or corner reflectors. It makes no sense to put an omni antenna in service where all of the potential users are in one sector. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com [mailto:Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com] On Behalf Of W3ML Sent: Sunday, October 11, 2009 7:09 AM To: Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com Subject: [Repeater-Builder] Antenna question Hi again, We are looking to replace that used antenna after getting 100 feet of new Andrew 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] Antenna question
How much line loss do you have? It could simply be an open at the connector on the antenna end. Try checking with an ohmmeter on the ground. It should show as a short from the center pin to the connector shell. Chuck WB2EDV - Original Message - From: Ian Miller [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, September 05, 2008 9:43 AM Subject: [Repeater-Builder] Antenna question Our group has a Sinclair 8 dipole array for UHF. The repeater was recently moved, and has not been behaving as usual. It hears OK, but seems weak on transmit. One of the members went up to the site last night with an MFJ antenna analyser - and he measured SWR at 3:1 - with no real resonant point. Our old UHF beam that was on the same tower and same feedline had an SWR of 1.5:1 measured on the same analyser. Is this method of measurement on an 8 dipole antenna correct? We have not put an SWR bridge on it. For the moment the repeater is off the air until the antenna question is resolved. What is inside the guts of one of those 8-bay antennas? Do they have a weak point where a bad connection can occur? Thanks Ian VA2IR Yahoo! Groups Links
RE: [Repeater-Builder] Antenna question
I have seen problems with using analyzers on dipole arrays, hopefully the bridge will give you a better report. Also might be an open connector as mentioned. Don Kirchner From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Ian Miller Sent: Friday, September 05, 2008 8:44 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Antenna question Our group has a Sinclair 8 dipole array for UHF. The repeater was recently moved, and has not been behaving as usual. It hears OK, but seems weak on transmit. One of the members went up to the site last night with an MFJ antenna analyser - and he measured SWR at 3:1 - with no real resonant point. Our old UHF beam that was on the same tower and same feedline had an SWR of 1.5:1 measured on the same analyser. Is this method of measurement on an 8 dipole antenna correct? We have not put an SWR bridge on it. For the moment the repeater is off the air until the antenna question is resolved. What is inside the guts of one of those 8-bay antennas? Do they have a weak point where a bad connection can occur? Thanks Ian VA2IR
Re: [Repeater-Builder] Antenna question
--- On Fri, 9/5/08, Ian Miller [EMAIL PROTECTED] wrote: From: Ian Miller [EMAIL PROTECTED] Subject: [Repeater-Builder] Antenna question To: Repeater-Builder@yahoogroups.com Date: Friday, September 5, 2008, 9:43 AM Our group has a Sinclair 8 dipole array for UHF. The repeater was recently moved, and has not been behaving as usual. It hears OK, but seems weak on transmit. One of the members went up to the site last night with an MFJ antenna analyser - and he measured SWR at 3:1 - with no real resonant point. Our old UHF beam that was on the same tower and same feedline had an SWR of 1.5:1 measured on the same analyser. Is this method of measurement on an 8 dipole antenna correct? We have not put an SWR bridge on it. I would use a real swr meter/directional watt meter on it. Sometimes those analizers will pick up power from other transmitters that are near it and not give a correct reading.
Re: [Repeater-Builder] Antenna question
Ian, As some others have pointed out, I too have seen a little odd response from the MFJ analyzer too. I very recently used one to toy around with several DB420 antennas. The MFJ wasn't wrong really, but it did not give the same response that two different SWR/Wattmeters powered by two different transmitters did (the Wattmeter SWR combos always matched). BTW: All of my testing was at the antenna feed point. In the end, reflected power at the transmitter and how well the system works in the real world are what are most important to me, but since you have real-world problems, jumping to the antenna in an attempt to start at one and and work your way back is the right thing to do. 73 DE N0MJS On Sep 5, 2008, at 8:43 AM, Ian Miller wrote: Our group has a Sinclair 8 dipole array for UHF. The repeater was recently moved, and has not been behaving as usual. It hears OK, but seems weak on transmit. One of the members went up to the site last night with an MFJ antenna analyser - and he measured SWR at 3:1 - with no real resonant point. Our old UHF beam that was on the same tower and same feedline had an SWR of 1.5:1 measured on the same analyser. Is this method of measurement on an 8 dipole antenna correct? We have not put an SWR bridge on it. For the moment the repeater is off the air until the antenna question is resolved. What is inside the guts of one of those 8-bay antennas? Do they have a weak point where a bad connection can occur? Thanks Ian VA2IR -- Cort Buffington H: +1-785-838-3034 M: +1-785-865-7206
Re: [Repeater-Builder] Antenna question
Impedance is impedance. The MFJ analyzer should be as accurate for that antenna as any other. However, the analyzer's signal is very small, and at any site where other transmitters are nearby, the analyzer's internal SWR bridge can be fooled by signals other than its own, leading to erroneous readings. You may need to use an external SWR bridge or directional wattmeter and run some significant power to get an accurate reading. That said, your symptoms suggest you have a real problem, possibly with the feedline, inter-element harness, or a connector. 73, Paul, AE4KR - Original Message - From: Ian Miller To: Repeater-Builder@yahoogroups.com Sent: Friday, September 05, 2008 7:43 AM Subject: [Repeater-Builder] Antenna question Our group has a Sinclair 8 dipole array for UHF. The repeater was recently moved, and has not been behaving as usual. It hears OK, but seems weak on transmit. One of the members went up to the site last night with an MFJ antenna analyser - and he measured SWR at 3:1 - with no real resonant point. Our old UHF beam that was on the same tower and same feedline had an SWR of 1.5:1 measured on the same analyser. Is this method of measurement on an 8 dipole antenna correct? We have not put an SWR bridge on it. For the moment the repeater is off the air until the antenna question is resolved. What is inside the guts of one of those 8-bay antennas? Do they have a weak point where a bad connection can occur? Thanks Ian VA2IR
Re: [Repeater-Builder] antenna question - Dip It and Scotch Kote and Krylon
For what it's worth, I'll add my two cents: After assembling and tuning a 2 meter Ringo antenna, I wiped it down with rubbing alcohol and then sprayed it with urethane spar (marine) varnish, which I bought at K-mart. I used an entire can (12 ounces maybe). The antenna performed well through twenty years of northeastern Ohio weather. That's when we moved and I had to take it down. Although there were a few places where the coating was wearing thin, most of it was still intact. I ended up throwing out the antenna because I couldn't get the darn PL-259 off. Between the tape and varnish, that bugger was set for life. I've also used this method on other antennas with excellent results; however the Ringo was up much longer than any of the others. If any of you want to try this, I offer two suggestions. First. and this is important, make sure the antenna is oil and grease free by wiping it down thoroughly with alcohol before applying the spar varnish. Afterwards, wear gloves or use a rag to handle it. Second, you might want to consider applying two coats of varnish, leaving sufficient time between coats for the antenna and feed-point connections to dry. 73 and aloha, Eric KH6CQ --- On Mon, 5/5/08, Wayne [EMAIL PROTECTED] wrote: From: Wayne [EMAIL PROTECTED] Subject: Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote and Krylon To: Repeater-Builder@yahoogroups.com Date: Monday, May 5, 2008, 2:56 AM 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 Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
Re: [Repeater-Builder] antenna question - Dip It and Scotch Kote and Kry
On Sun, 4 May 2008, Bruce Bagwell 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. Paint it any color but clear, copper, silver, or gold if you want to remain the owner of it. -- Kris Kirby, KE4AHR [EMAIL PROTECTED] But remember, with no superpowers comes no responsibility. --rly
RE: [Repeater-Builder] antenna question
At 08:44 AM 05/01/08, Ron Wright, N9EE wrote: (big chunk cut out) One other plus for folded dipole antennas, the fiberglass antennas are much more prone to become toothpicks with a lightning strike where a 224 will most likely survive. Plus in windy areas they need a top support to prevent self-destructive flexing. Yes. it will take some time to show up but it will happen eventually. The only prevention is to side mount it and buy the top support at the same time you buy the antenna and install them on the same trip. Mike
RE: [Repeater-Builder] antenna question
At 5/3/2008 11:44, you wrote: At 08:44 AM 05/01/08, Ron Wright, N9EE wrote: (big chunk cut out) One other plus for folded dipole antennas, the fiberglass antennas are much more prone to become toothpicks with a lightning strike where a 224 will most likely survive. Plus in windy areas they need a top support to prevent self-destructive flexing. Yes. it will take some time to show up but it will happen eventually. ...and when it does the effects can be very hideous. I once had desense on my 2 meter repeater that was caused by a UHF RX antenna 6 feet away from my RX only antenna (both antennas were on top of the tower, where no TXing was allowed). The bad antenna was a commercial fiberglass omni, about 10 to 12 ft. long. Bob NO6B
Re: [Repeater-Builder] antenna question
hi all, I am about to replace a DB224 side mounted at 1175 ft above ground. The antenna is close to the Gulf, 0.5 mi, and think the salt air got to it. It has been up about 12 years and now has an SWR of 2:1. The coverage is very noticeably less. I am thinking of a Super Station Master fiberglass enclosed antenna as a replacement. The Celwave/RFS 220 is my thinking. Any thoughts about this from some who have experience with salt air. I like the DB224 and many locally use them. I like being able to skew the pattern, but others locally have had similar salt air problems with VHF and UHF exposed dipoles. I've also seen the Super Station Masters last decades in harsh environments. 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: [Repeater-Builder] antenna question
Ron, I am a big proponent of the DB line of antennas but I also add that they must be set up correctly before they are installed, especially in a high humidity/salt air environment like you are talking about. The following is what I learned form the two engineers that developed the DB line of folded dipole antennas decades ago. I have posted this several times on R/B and will do it again. When you get a brand new antenna from DB you must take all the nuts off where the coax connects to the dipoles and tighten the screws and nuts through the dipole, you will find many are finger tight. Once these screws and nuts are tight then put the coax terminal back on the dipole. 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. Warning, don't get it on your skin, you will wear it for several days. You can clean it up a little with MEK. By the way, I did some research and MEK is not as bad of a carcinogen as some people would lead you to believe. I have installed several DB 224 antennas in the Tampa area with this method with few problems. While the fiberglass antennas have the radome they are still vented to the salt air and you can't get in them to seal the potential bimetal corrosion problems like you can the DB antennas. One other plus for folded dipole antennas, the fiberglass antennas are much more prone to become toothpicks with a lightning strike where a 224 will most likely survive. Paul -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Ron Wright Sent: Thursday, May 01, 2008 9:39 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] antenna question hi all, I am about to replace a DB224 side mounted at 1175 ft above ground. The antenna is close to the Gulf, 0.5 mi, and think the salt air got to it. It has been up about 12 years and now has an SWR of 2:1. The coverage is very noticeably less. I am thinking of a Super Station Master fiberglass enclosed antenna as a replacement. The Celwave/RFS 220 is my thinking. Any thoughts about this from some who have experience with salt air. I like the DB224 and many locally use them. I like being able to skew the pattern, but others locally have had similar salt air problems with VHF and UHF exposed dipoles. I've also seen the Super Station Masters last decades in harsh environments. 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. Yahoo! Groups Links No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.7/1408 - Release Date: 4/30/2008 6:10 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.7/1408 - Release Date: 4/30/2008 6:10 PM 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: RE: [Repeater-Builder] antenna question
Paul, I know this DB224 was prepared for the weather. I was not the one who did it, but know the person who did and he is very particular. He has same problem with other exposed dipole antennas close to the gulf. I will check to see what coating he used. I did see him prepare a DB224 for install. All of what you did was done, but not sure about this antenna. 73, ron, n9ee/r From: Paul Finch [EMAIL PROTECTED] Date: 2008/05/01 Thu AM 10:44:37 CDT To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] antenna question Ron, I am a big proponent of the DB line of antennas but I also add that they must be set up correctly before they are installed, especially in a high humidity/salt air environment like you are talking about. The following is what I learned form the two engineers that developed the DB line of folded dipole antennas decades ago. I have posted this several times on R/B and will do it again. When you get a brand new antenna from DB you must take all the nuts off where the coax connects to the dipoles and tighten the screws and nuts through the dipole, you will find many are finger tight. Once these screws and nuts are tight then put the coax terminal back on the dipole. 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. Warning, don't get it on your skin, you will wear it for several days. You can clean it up a little with MEK. By the way, I did some research and MEK is not as bad of a carcinogen as some people would lead you to believe. I have installed several DB 224 antennas in the Tampa area with this method with few problems. While the fiberglass antennas have the radome they are still vented to the salt air and you can't get in them to seal the potential bimetal corrosion problems like you can the DB antennas. One other plus for folded dipole antennas, the fiberglass antennas are much more prone to become toothpicks with a lightning strike where a 224 will most likely survive. Paul -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Ron Wright Sent: Thursday, May 01, 2008 9:39 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] antenna question hi all, I am about to replace a DB224 side mounted at 1175 ft above ground. The antenna is close to the Gulf, 0.5 mi, and think the salt air got to it. It has been up about 12 years and now has an SWR of 2:1. The coverage is very noticeably less. I am thinking of a Super Station Master fiberglass enclosed antenna as a replacement. The Celwave/RFS 220 is my thinking. Any thoughts about this from some who have experience with salt air. I like the DB224 and many locally use them. I like being able to skew the pattern, but others locally have had similar salt air problems with VHF and UHF exposed dipoles. I've also seen the Super Station Masters last decades in harsh environments. 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. Yahoo! Groups Links No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.7/1408 - Release Date: 4/30/2008 6:10 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.7/1408 - Release Date: 4/30/2008 6:10 PM 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] antenna question
Paul Finch wrote: I have posted this several times on R/B and will do it again. When you get Maybe it should be an article? :-) Nate WY0X
Re: RE: [Repeater-Builder] antenna question
Paul, I talked with my friend about the DB224. He said as you did. When you get it you have to tighten the hardware. Some was more than finger loose. This is for all antennas, but more for DB Products. He has used the Scotchkote. He likes it, but noted lasted only 3-5 years. He has remove antennas it was used on and at places where he had put black tape then coated it with the Scotchkote the tape was there, but the Scotchkote was gone especially on the side of the sun exposure. He did not know what the MEK was. Another problem he and I also have seen with the DB224 is where the high side of the coax connects to the folded dipoles. There is a small think fiberglass tubing to secure the loop ends together. We have noted on antennas that have been up for a while this piece is either gone or badly damaged. Mainly a structure component. I'm giving myself about a week to think on the DB224 or Station Master. I like both, but lean toward the Station Master. 73, ron, n9ee/r From: Paul Finch [EMAIL PROTECTED] Date: 2008/05/01 Thu AM 10:44:37 CDT To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] antenna question Ron, I am a big proponent of the DB line of antennas but I also add that they must be set up correctly before they are installed, especially in a high humidity/salt air environment like you are talking about. The following is what I learned form the two engineers that developed the DB line of folded dipole antennas decades ago. I have posted this several times on R/B and will do it again. When you get a brand new antenna from DB you must take all the nuts off where the coax connects to the dipoles and tighten the screws and nuts through the dipole, you will find many are finger tight. Once these screws and nuts are tight then put the coax terminal back on the dipole. 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. Warning, don't get it on your skin, you will wear it for several days. You can clean it up a little with MEK. By the way, I did some research and MEK is not as bad of a carcinogen as some people would lead you to believe. I have installed several DB 224 antennas in the Tampa area with this method with few problems. While the fiberglass antennas have the radome they are still vented to the salt air and you can't get in them to seal the potential bimetal corrosion problems like you can the DB antennas. One other plus for folded dipole antennas, the fiberglass antennas are much more prone to become toothpicks with a lightning strike where a 224 will most likely survive. Paul -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Ron Wright Sent: Thursday, May 01, 2008 9:39 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] antenna question hi all, I am about to replace a DB224 side mounted at 1175 ft above ground. The antenna is close to the Gulf, 0.5 mi, and think the salt air got to it. It has been up about 12 years and now has an SWR of 2:1. The coverage is very noticeably less. I am thinking of a Super Station Master fiberglass enclosed antenna as a replacement. The Celwave/RFS 220 is my thinking. Any thoughts about this from some who have experience with salt air. I like the DB224 and many locally use them. I like being able to skew the pattern, but others locally have had similar salt air problems with VHF and UHF exposed dipoles. I've also seen the Super Station Masters last decades in harsh environments. 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. Yahoo! Groups Links No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.7/1408 - Release Date: 4/30/2008 6:10 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.7/1408 - Release Date: 4/30/2008 6:10 PM 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: RE: [Repeater-Builder] antenna question
Have you considered a DB-264E? 73 de N5NPO Norm - Original Message - From: Repeater-Builder@yahoogroups.com Repeater-Builder@yahoogroups.com To: Repeater-Builder@yahoogroups.com Repeater-Builder@yahoogroups.com Sent: Thu May 01 18:43:03 2008 Subject: Re: RE: [Repeater-Builder] antenna question Paul, I talked with my friend about the DB224. He said as you did. When you get it you have to tighten the hardware. Some was more than finger loose. This is for all antennas, but more for DB Products. He has used the Scotchkote. He likes it, but noted lasted only 3-5 years. He has remove antennas it was used on and at places where he had put black tape then coated it with the Scotchkote the tape was there, but the Scotchkote was gone especially on the side of the sun exposure. He did not know what the MEK was. Another problem he and I also have seen with the DB224 is where the high side of the coax connects to the folded dipoles. There is a small think fiberglass tubing to secure the loop ends together. We have noted on antennas that have been up for a while this piece is either gone or badly damaged. Mainly a structure component. I'm giving myself about a week to think on the DB224 or Station Master. I like both, but lean toward the Station Master. 73, ron, n9ee/r From: Paul Finch [EMAIL PROTECTED] mailto:dpaulfinch%40azlecomm.com Date: 2008/05/01 Thu AM 10:44:37 CDT To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: RE: [Repeater-Builder] antenna question Ron, I am a big proponent of the DB line of antennas but I also add that they must be set up correctly before they are installed, especially in a high humidity/salt air environment like you are talking about. The following is what I learned form the two engineers that developed the DB line of folded dipole antennas decades ago. I have posted this several times on R/B and will do it again. When you get a brand new antenna from DB you must take all the nuts off where the coax connects to the dipoles and tighten the screws and nuts through the dipole, you will find many are finger tight. Once these screws and nuts are tight then put the coax terminal back on the dipole. 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. Warning, don't get it on your skin, you will wear it for several days. You can clean it up a little with MEK. By the way, I did some research and MEK is not as bad of a carcinogen as some people would lead you to believe. I have installed several DB 224 antennas in the Tampa area with this method with few problems. While the fiberglass antennas have the radome they are still vented to the salt air and you can't get in them to seal the potential bimetal corrosion problems like you can the DB antennas. One other plus for folded dipole antennas, the fiberglass antennas are much more prone to become toothpicks with a lightning strike where a 224 will most likely survive. Paul -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of Ron Wright Sent: Thursday, May 01, 2008 9:39 AM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: Re: [Repeater-Builder] antenna question hi all, I am about to replace a DB224 side mounted at 1175 ft above ground. The antenna is close to the Gulf, 0.5 mi, and think the salt air got to it. It has been up about 12 years and now has an SWR of 2:1. The coverage is very noticeably less. I am thinking of a Super Station Master fiberglass enclosed antenna as a replacement. The Celwave/RFS 220 is my thinking. Any thoughts about this from some who have experience with salt air. I like the DB224 and many locally use them. I like being able to skew the pattern, but others locally have had similar salt air problems with VHF and UHF exposed dipoles. I've also seen the Super Station Masters last decades in harsh environments. 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. Yahoo! Groups Links No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.7/1408 - Release Date: 4/30/2008 6:10 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.7/1408 - Release Date: 4/30/2008 6:10 PM 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] antenna question
Ron Wright wrote: I'm giving myself about a week to think on the DB224 or Station Master. I like both, but lean toward the Station Master. Heh, my usual comment... everyone will be expecting this one... Have you considered a Sinclair with the harness internal to the antenna? I still think that's the elegant solution to the above question. You still get the dipole array, but keep the harness out of the sunlight and weather. Ultimately it is up to personal preference. Like a lot of things, if you like it, you'll put up with problems from it and fix it. (Why people drive and rebuild classic cars... even though they're not nearly as reliable as say, an early 90's Honda Civic. Because the Civic is boring.) If you don't like it, you'll get ticked off when you have to fix it, and it won't be fun. :-) Nate WY0X
RE: RE: [Repeater-Builder] antenna question
Take a look at the Antenex YDAF series. These antenna's are manufactured by Bluewave for Antenex. Jeff -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Ron Wright Sent: Thursday, May 01, 2008 4:43 PM To: Repeater-Builder@yahoogroups.com Subject: Re: RE: [Repeater-Builder] antenna question Paul, I talked with my friend about the DB224. He said as you did. When you get it you have to tighten the hardware. Some was more than finger loose. This is for all antennas, but more for DB Products. He has used the Scotchkote. He likes it, but noted lasted only 3-5 years. He has remove antennas it was used on and at places where he had put black tape then coated it with the Scotchkote the tape was there, but the Scotchkote was gone especially on the side of the sun exposure. He did not know what the MEK was. Another problem he and I also have seen with the DB224 is where the high side of the coax connects to the folded dipoles. There is a small think fiberglass tubing to secure the loop ends together. We have noted on antennas that have been up for a while this piece is either gone or badly damaged. Mainly a structure component. I'm giving myself about a week to think on the DB224 or Station Master. I like both, but lean toward the Station Master. 73, ron, n9ee/r
Re: Re: [Repeater-Builder] antenna question
Nate, My problem is not the harness, but the exposed dipoles. 73, ron, n9ee/r From: Nate Duehr [EMAIL PROTECTED] Date: 2008/05/01 Thu PM 07:00:56 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] antenna question Ron Wright wrote: I'm giving myself about a week to think on the DB224 or Station Master. I like both, but lean toward the Station Master. Heh, my usual comment... everyone will be expecting this one... Have you considered a Sinclair with the harness internal to the antenna? I still think that's the elegant solution to the above question. You still get the dipole array, but keep the harness out of the sunlight and weather. Ultimately it is up to personal preference. Like a lot of things, if you like it, you'll put up with problems from it and fix it. (Why people drive and rebuild classic cars... even though they're not nearly as reliable as say, an early 90's Honda Civic. Because the Civic is boring.) If you don't like it, you'll get ticked off when you have to fix it, and it won't be fun. :-) 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] Antenna Question
Hello, Like he said, it depends on several things. You have to consider the Antennas, power, frequency, split and quality of receiver and transmitter. On the receiver you have to look at selectivity and on the transmitter you have to look at transmit noise. I have 80 feet between my two high band antennas running a 2 meter repeater with no desense at all and no filtering. I have seen as little as 60 feet on an old GE Progress line repeater, the first repeater I ever built. The tower was only 120 feet so more would have made the repeater fairly ineffective. It also worked well with 60 watts out. If you are using something like a GE Mastr II or equivalent you could probably go as close as 60 feet with no desense. If you find you do have desense or transmit noise problem you can always use a couple of notch filters to correct the problem with little system loss. Best thing to do is try it and see what happens and address problems later. That's the fun of Ham Radio. Paul _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Monday, April 21, 2008 9:06 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Antenna Question It depends on band, split, power, and antenna gain. On Tue, 22 Apr 2008 02:00:23 - Christopher Hodgdon HYPERLINK mailto:chris.hodgdon%40kaufman-ares.org[EMAIL PROTECTED] wrote: We are looking at setting up a basic (I know there is no such thing) repeater. What I need to know, if you do not have a duplexer to run your antenna through, but have two antennas, with one on the TX and one on the RX how far apart do they have to be to be able to correctly operate? No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.2/1388 - Release Date: 4/20/2008 3:01 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.3/1390 - Release Date: 4/21/2008 4:23 PM
Re: [Repeater-Builder] Antenna Question
At 07:00 PM 04/21/08, you wrote: We are looking at setting up a basic (I know there is no such thing) repeater. What I need to know, if you do not have a duplexer to run your antenna through, but have two antennas, with one on the TX and one on the RX how far apart do they have to be to be able to correctly operate? http://www.repeater-builder.com/antenna/separation.html http://www.repeater-builder.com/antenna/thoughts-on-isolation.html Mike WA6ILQ
Re: [Repeater-Builder] Antenna Question
It depends on band, split, power, and antenna gain. On Tue, 22 Apr 2008 02:00:23 - Christopher Hodgdon [EMAIL PROTECTED] wrote: We are looking at setting up a basic (I know there is no such thing) repeater. What I need to know, if you do not have a duplexer to run your antenna through, but have two antennas, with one on the TX and one on the RX how far apart do they have to be to be able to correctly operate?
RE: [Repeater-Builder] Antenna Question
Christopher, According to my CommShop program, a 144 MHz repeater with a 50 watt transmitter and a receiver having 0.3 uV sensitivity will require around 90 dB of isolation to avoid desense with a typical receiver. That isolation can be achieved with about 220 feet of vertical separation or about 21,300 feet (four miles!) of horizontal separation. I made the assumption that you're planning a 2m repeater, which has only 600 kHz of TX-RX separation. If the repeater is going to be a 70cm machine, with 5 MHz separation, the numbers are easier to swallow. With the same power level and sensitivity, a vertical separation of 40 feet or a horizontal separation of 975 feet would give the needed 72 dB isolation. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Christopher Hodgdon Sent: Monday, April 21, 2008 7:00 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Antenna Question We are looking at setting up a basic (I know there is no such thing) repeater. What I need to know, if you do not have a duplexer to run your antenna through, but have two antennas, with one on the TX and one on the RX how far apart do they have to be to be able to correctly operate?
Re: Re: [Repeater-Builder] Antenna question
There is a DB224 with internal harness. Not made for Ham band, but for 150-160, etc. 73, ron, n9ee/r From: Larry Wagoner [EMAIL PROTECTED] Date: 2008/03/24 Mon PM 05:41:52 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Antenna question At 05:37 PM 3/24/2008, you wrote: You may have something else. The SRL-224 has an external harness. Hmmm - this thing has a harness interior to the mast and which runs through the center of the arms which hold the bays. Ideas? Larry N5WLW 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] Antenna question
Maybe that's what he has, even though he said it wasn't a DB products. But he said antenna rod, not tubing. Was that particular model made with rod? Chuck WB2EDV - Original Message - From: Ron Wright [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, March 25, 2008 7:57 AM Subject: Re: Re: [Repeater-Builder] Antenna question There is a DB224 with internal harness. Not made for Ham band, but for 150-160, etc. 73, ron, n9ee/r From: Larry Wagoner [EMAIL PROTECTED] Date: 2008/03/24 Mon PM 05:41:52 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Antenna question At 05:37 PM 3/24/2008, you wrote: You may have something else. The SRL-224 has an external harness. Hmmm - this thing has a harness interior to the mast and which runs through the center of the arms which hold the bays. Ideas? Larry N5WLW 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: Re: [Repeater-Builder] Antenna question
At 10:07 AM 3/25/2008, you wrote: Maybe that's what he has, even though he said it wasn't a DB products. But he said antenna rod, not tubing. Was that particular model made with rod? Chuck - have been told by someone else that it is a Sinclair. I can find no tag or ID on it that tells me that - so I am looking for information. I hope to grab a digital pix of the thing - or at least one of the bays - to help people figure out what it is. Thing is - on the MFJ 259 - it seems to be resonant at 147.1 Thanks. Larry N5WLW
Re: [Repeater-Builder] Antenna question
You may have something else. The SRL-224 has an external harness. Chuck WB2EDV - Original Message - From: Larry Wagoner [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, March 24, 2008 6:09 PM Subject: [Repeater-Builder] Antenna question I have what may see to be a dumb question ... I have in my possession what I am told is a Sinclair 224 VHF four-bay folded dipole. My MFJ 259 says the antenna is resonant at 147.1 - which is close enough for the frequency where I want to use it: 145.150. This is an older antenna - and I am wondering - if I determine that the harness is faulty - is there a way to make up a harness to run external to the mast like a DB 224 does? Larry N5WLW Yahoo! Groups Links
Re: [Repeater-Builder] Antenna question
At 05:37 PM 3/24/2008, you wrote: You may have something else. The SRL-224 has an external harness. Hmmm - this thing has a harness interior to the mast and which runs through the center of the arms which hold the bays. Ideas? Larry N5WLW
Re: [Repeater-Builder] Antenna question
Is there a blob of heat-shrink tubing at the middle of the element - furthest away from the mast? If so, that sounds like their SRL-210C-4. Go look on the Sinclair web site. Chuck WB2EDV - Original Message - From: Larry Wagoner [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, March 24, 2008 6:41 PM Subject: Re: [Repeater-Builder] Antenna question At 05:37 PM 3/24/2008, you wrote: You may have something else. The SRL-224 has an external harness. Hmmm - this thing has a harness interior to the mast and which runs through the center of the arms which hold the bays. Ideas? Larry N5WLW Yahoo! Groups Links
Re: [Repeater-Builder] Antenna question
At 05:48 PM 3/24/2008, you wrote: Is there a blob of heat-shrink tubing at the middle of the element - furthest away from the mast? Nope - just aluminum rod Larry N5WLW
Re: [Repeater-Builder] Antenna question
At 05:48 PM 3/24/2008, you wrote: Is there a blob of heat-shrink tubing at the middle of the element - furthest away from the mast? One other thing ... the arms holding the dipole away from the mast is only about 8 inches long - and extends to both the inside and outside of the dipole. Not sure how to describe this ... Larry N5WLW
Re: [Repeater-Builder] Antenna question
Could you find it on the Sinclair web site? How about a picture of one of the elements? You can email one to me. Chuck wb2edv at roadrunner dot com - Original Message - From: Larry Wagoner [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, March 24, 2008 7:28 PM Subject: Re: [Repeater-Builder] Antenna question At 05:48 PM 3/24/2008, you wrote: Is there a blob of heat-shrink tubing at the middle of the element - furthest away from the mast? Nope - just aluminum rod Larry N5WLW
Re: [Repeater-Builder] Antenna question
Than it's not a SRL-224. On those, the element attaches directly to the mast (and the harness is external). Chuck WB2EDV - Original Message - From: Larry Wagoner [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, March 24, 2008 7:36 PM Subject: Re: [Repeater-Builder] Antenna question At 05:48 PM 3/24/2008, you wrote: Is there a blob of heat-shrink tubing at the middle of the element - furthest away from the mast? One other thing ... the arms holding the dipole away from the mast is only about 8 inches long - and extends to both the inside and outside of the dipole. Not sure how to describe this ... Larry N5WLW Yahoo! Groups Links
Re: [Repeater-Builder] Antenna question for the forum.
Hi Steve, First, avoid using LMR-400 for duplex use. This and 9913 are not good for duplex. Aluminum shield and tinned copper braid rubbing together and setting up corrosion causing noise. This is not a very long run, try and get some 1/2 hardline, you will not be disappointed. Spend all you can on antenna and feedline. Take a look at the Hustler G6-270R antenna. Short and one piece, you only need to install the radials. (Use No-OX on the bolts that holed them in when building.)Low angle of radiation, built pretty solid. N connector. And the bonus is you can add a Diplexer in the repeater cabinet to add a 440 control receiver. I have this setup at 150' on a cell tower and it has unbelievable coverage. I have had a G7-144 in the air for almost 20 years, no problem. Top mounted at 71' to the tip. The G6-144 has less sturdy radials and a little less gain. They both will last a long time but figure on replacing ANY fiberglass antenna 15-20 years down the road even if it don't get a direct hit. The fiberglass just weathers out. Not to mention some of them suffer broken connections internally. Oh, by the way all of the Hustler antennas mentioned are DC shorted so less likely to take a hit if grounded properly. The Diamond and Comet antennas will probably only last one or two seasons in your weather! I could write two pages of faults in construction on these brands. Just not build sturdy enough. They don't last long here in Michigan. I am in the Detroit area. Good Luck, Shanon KA8SPW 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 [EMAIL PROTECTED] Yahoo! Groups Links
Re: [Repeater-Builder] Antenna question for the forum.
At 02:24 PM 2/1/2008, you wrote: Hi Steve, The Diamond and Comet antennas will probably only last one or two seasons in your weather! I could write two pages of faults in construction on these brands. Just not build sturdy enough. They don't last long here in Michigan. I am in the Detroit area. ---Of course, YMMV. I used a Diamond X3000 at the 10,000' level on Mt. Haleakala on Maui for many years with no problems (believe it or not, lots of ice buildup and 80+ MPH winds during the winter is quite common. I was running a Diamond F22 on a UHF repeater for several years as well with no problems here in Oregon. I am now using a Diamond X510 with likewise great results. The secret is to not trust their o-ring seals and use some of that weatherproof goop on the joints. In my case, I also use a fiberglass arm at the 15' point (side mounted on a 160' tower) of the antenna's radome for additional support. Diamond antenna are great for long term repeater use IF you do some minor mods as above. And they perform like all get out to boot! Ken (my 2 cents) -- President and CTO - Arcom Communications Makers of repeater controllers and accessories. http://www.arcomcontrollers.com/ Authorized Dealers for Kenwood and Telewave and we offer complete repeater packages! AH6LE/R - IRLP Node 3000 http://www.irlp.net We don't just make 'em. We use 'em!
Re: [Repeater-Builder] Antenna question for the forum.
If either takes a lightning strike the fiberglass will explode. I have had that happen with both. Check into Tram antennas. they seem electrically and mechanically similar to the diamond but are a lot cheaper! WB5OXQ - Original Message - From: w2sxk To: Repeater-Builder@yahoogroups.com Sent: Friday, January 25, 2008 3:43 PM Subject: [Repeater-Builder] Antenna question for the forum. 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 [EMAIL PROTECTED]
Re: [Repeater-Builder] Antenna question for the forum.
Check out: www.repeater-builder.com/products Look under the antenna section for Tram antennas. Scott Scott Zimmerman Amateur Radio Call N3XCC 612 Barnett Road Boswell, PA 15531 - Original Message - From: Jim Miller WB5OXQ in Waco To: Repeater-Builder@yahoogroups.com Sent: Saturday, January 26, 2008 2:59 PM Subject: Re: [Repeater-Builder] Antenna question for the forum. If either takes a lightning strike the fiberglass will explode. I have had that happen with both. Check into Tram antennas. they seem electrically and mechanically similar to the diamond but are a lot cheaper! WB5OXQ - Original Message - From: w2sxk To: Repeater-Builder@yahoogroups.com Sent: Friday, January 25, 2008 3:43 PM Subject: [Repeater-Builder] Antenna question for the forum. 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 [EMAIL PROTECTED] -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.16/1251 - Release Date: 1/30/2008 9:29 AM
Re: [Repeater-Builder] Antenna question for the forum.
You'll hear this from others -- DO NOT use the LMR-400 cable in duplex situations. This subject comes up about every other week here. Chuck WB2EDV - Original Message - From: w2sxk [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, January 25, 2008 4:43 PM Subject: [Repeater-Builder] Antenna question for the forum. 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 [EMAIL PROTECTED]
RE: [Repeater-Builder] Antenna Question
Hi Rod, That antenna we started using for our Passport system here in Oregon and had many problems with the antenna. It will eventually fail you. We use exclusively the Telewave ANT150D antenna have had NO problems. Mike Oregon Repeater Linking Group Mike Mullarkey -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Friday, December 30, 2005 11:52 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Antenna Question Hello to the list. Has anyone used or using the MFB1503 Series antenna as a repeater antenna? If so, what do you think of it? This will be for 2 meter use, at about 3,200' here in Washington state; will get ice and snow build up. Any comments? Thank you. Rod Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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] antenna question for 2M ham. . .
If you have your wind averages sticking a Big ole stick in the sky I found this web site useful in planning wind loads. try http://www.championradio.com/tn-topten-mistakes.html Good place for anyone to start. I searched MSN and used the words Radio + Antenna + Wind + Load there is some stuff technical in nature nad some in PDF file Mark Holman AB8RU Happy Holidays - Original Message - From: talviar4499 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, December 21, 2004 1:45 PM Subject: [Repeater-Builder] antenna question for 2M ham. . . OK. One of the repeaters I help maintain (145.170 located in Connellsville, PA on the mountain) recently lost an antenna in the wind storms that hit us around the beginning of December. Antenna we had on the tower was a Celwave PD340-3 (If you have never seen a 4 bay folded dipole with the top 3/4 of the antenna flapping in the wind, trust me you don't want to. . . Saw the darn thing in the middle of the wind storm blowing straight out side ways from the tower holding on by the harness. . . ) Past experience with trying to find a new replacement shows that Celwave doesn't make this model anymore. (Last summer replacing the antenna on 147.045 for W3PIE) Along the lines of the 4 Bay folded dipole arrays what does anyone recommend? (Familiar with the DB224E antenna) Anyone making these with an internal harness instead of an external harness? (Weather in SW PA is not user friendly especially when putting the antennas on the top of a mountain) If this has been covered in the list prior I apologize, have not had time to look in the archives so if covered prior give me a rough idea of when so I can look. Otherwise, reply on the list or direct to [EMAIL PROTECTED] would be appreciated. Thanks Tony, KA3VOR Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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] antenna question for 2M ham. . .
Sinclair makes excellent dipoles. We switched to them several years ago and never looked back. http://www.sinctech.com/ Mike K6MJU OK. One of the repeaters I help maintain (145.170 located in Connellsville, PA on the mountain) recently lost an antenna in the wind storms that hit us around the beginning of December. Antenna we had on the tower was a Celwave PD340-3 (If you have never seen a 4 bay folded dipole with the top 3/4 of the antenna flapping in the wind, trust me you don't want to. . . Saw the darn thing in the middle of the wind storm blowing straight out side ways from the tower holding on by the harness. . . ) Past experience with trying to find a new replacement shows that Celwave doesn't make this model anymore. (Last summer replacing the antenna on 147.045 for W3PIE) Along the lines of the 4 Bay folded dipole arrays what does anyone recommend? (Familiar with the DB224E antenna) Anyone making these with an internal harness instead of an external harness? (Weather in SW PA is not user friendly especially when putting the antennas on the top of a mountain) If this has been covered in the list prior I apologize, have not had time to look in the archives so if covered prior give me a rough idea of when so I can look. Otherwise, reply on the list or direct to [EMAIL PROTECTED] would be appreciated. Thanks Tony, KA3VOR Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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] antenna question for 2M ham. . .
Yes they do. Chuck WB2EDV - Original Message - From: mike [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, December 21, 2004 3:42 PM Subject: Re: [Repeater-Builder] antenna question for 2M ham. . . Sinclair makes excellent dipoles. We switched to them several years ago and never looked back. http://www.sinctech.com/ Mike K6MJU OK. One of the repeaters I help maintain (145.170 located in Connellsville, PA on the mountain) recently lost an antenna in the wind storms that hit us around the beginning of December. Antenna we had on the tower was a Celwave PD340-3 (If you have never seen a 4 bay folded dipole with the top 3/4 of the antenna flapping in the wind, trust me you don't want to. . . Saw the darn thing in the middle of the wind storm blowing straight out side ways from the tower holding on by the harness. . . ) Past experience with trying to find a new replacement shows that Celwave doesn't make this model anymore. (Last summer replacing the antenna on 147.045 for W3PIE) Along the lines of the 4 Bay folded dipole arrays what does anyone recommend? (Familiar with the DB224E antenna) Anyone making these with an internal harness instead of an external harness? (Weather in SW PA is not user friendly especially when putting the antennas on the top of a mountain) If this has been covered in the list prior I apologize, have not had time to look in the archives so if covered prior give me a rough idea of when so I can look. Otherwise, reply on the list or direct to [EMAIL PROTECTED] would be appreciated. Thanks Tony, KA3VOR Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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/
