RE: [Repeater-Builder] Usage of Linked Repeater Systems vs. Stand Alone Repeaters
I had a UHF machine which simply passed user PL with flat enough response to achieve the same effect. Then, I got complaints from my control ops that during autopatches, they could hear only the telephone side of the conversation. Just can't win! 73, Paul, AE4KR _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Nate Duehr Sent: Friday, November 23, 2007 9:18 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Usage of Linked Repeater Systems vs. Stand Alone Repeaters On Nov 22, 2007, at 12:31 PM, Paul Plack wrote: For long-term monitoring, a repeater with inconspicuous CWID, minimalist courtesy tones and delays to kill squelch tails gets my vote every time. We built a machine that CTCSS TX from the repeater follows user input (user CTCSS in) -- the original reason was to do in-band linking for an EchoIRLP node. As an interesting side-effect, we've had a number of pleased reports from hams who've used commercial systems (and many who have commercial radios that have proper Reverse Burst or STE) who really like the SOUND of a dead quiet repeater where they don't even hear the repeater ID if it goes off in-between transmissions. The interesting part about that kind of setup is the techies/geeks who want the courtesy tones and gadgets can have them, they just run their receivers without CTCSS. Those things play, but aren't heard by anyone using CTCSS decoders. Something to think about for those looking for something new to play with. -- Nate Duehr, WY0X [EMAIL PROTECTED] mailto:nate%40natetech.com com
[Repeater-Builder] Re: Icom gives 5 more D-Star repeaters to the WIA
--- In Repeater-Builder@yahoogroups.com, Mark Thompson [EMAIL PROTECTED] wrote: Icom gives 5 more D-Star repeaters to the WIA . Let's see, iCOM gives away repeaters that can only be used with iCOM radios.
RE: [Repeater-Builder] Re: Icom gives 5 more D-Star repeaters to the WIA
Explaining the continued lack of interest in those specific repeaters.. Personally the conversion process of a junker IS the journey To: Repeater-Builder@yahoogroups.com From: [EMAIL PROTECTED] Date: Sat, 24 Nov 2007 10:20:27 + Subject: [Repeater-Builder] Re: Icom gives 5 more D-Star repeaters to the WIA --- In Repeater-Builder@yahoogroups.com, Mark Thompson [EMAIL PROTECTED] wrote: Icom gives 5 more D-Star repeaters to the WIA . Let's see, iCOM gives away repeaters that can only be used with iCOM radios. _ What are you waiting for? Join Lavalife FREE http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Flavalife9%2Eninemsn%2Ecom%2Eau%2Fclickthru%2Fclickthru%2Eact%3Fid%3Dninemsn%26context%3Dan99%26locale%3Den%5FAU%26a%3D30288_t=764581033_r=email_taglines_Join_free_OCT07_m=EXT
Re: [Repeater-Builder] Repeater Antenna Choice
I'd vote to stay with what you are using. You could decrease performance to hand-helds closer in if you go with a higher gain antenna, not to mention the added cost of the bigger antenna, more wind load, more weight, greater flexing (unless there's a top bracket). You'll see 3 dB increase at the horizon. Is this where you need coverage? If you've got a lot of users out at the very edge of coverage, it may make sense. Chuck WB2EDV - Original Message - From: Derek [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, November 23, 2007 5:55 PM Subject: [Repeater-Builder] Repeater Antenna Choice I'm looking for input on what kind of antenna to use for several 440 MHz amateur repeaters. Background: Suburban area surrounding metropolitan city of about 700,000. HAGL for antennas range from 260' to 320' on 400' and 500' towers. I'm looking to maximize mobile and portable input, even possibly looking to use 1-5/8 heliax as I recently installed this size hardline on my repeater and have been very satisfied with the results. I've used the DB-408 antenna and am happy with it's performance, but am wondering about significant difference in using a DB-420 for future repeaters. Also considering the RFS 1151 (Tessco # 435830) fiberglass antenna. It is tuned for 440-450 MHz and has 8dB gain, but I've heard some say fiberglass is not the way to go for repeaters. Any thoughts are appreciated. Derek Yahoo! Groups Links
[Repeater-Builder] Re: Repeater Antenna Choice
Derek, Going to the higher gain antenna may cause shadowing in some areas close in to the repeater site if its up real high. I also like the DB-408 antennas and am using them on my systems. The fiberglass antennas are OK also, But if they take a lightning hit they are gone. I had an ASP copy of a DB813 on a water tower and it took a direct hit and it still worked great. I had a big burn mark on one of the loops. It also had a red plastic cap on the top and it was burned and blackened. To me the loop style antennas are the way to go for antennas in areas the there is a good chance of being hit by lightning. If you are going to sidemount a fiberglass antenna you need to be 3 to 6 feet out from the side of the tower as the fiberglass antennas need room to flex. An arm out to the upper part of the fiberglass antenna is a good idea. With the antenna manufactures going overseas to build antennas the quality is not like the ones we got years ago. You may want to look at COMPROD antennas. There web site is www.comprodcom.com they build great antennas. 73 from Paul W9DWP
RE: [Repeater-Builder] Micor Repeaters Available
hu to bad for me,we would have need one for our radio club here :- http://www.emoticonesgratuites.ca/?icid=EMFRCA120
RE: [Repeater-Builder] Re: Icom gives 5 more D-Star repeaters to the WIA
to bad it does not arrived around here i would have tried this DSTAR system but for the moment i find the $$$ a little to much for an ham radio club that by definition have no money most of the time but many whishes gervais ve2ckn To: [EMAIL PROTECTED]: [EMAIL PROTECTED]: Sat, 24 Nov 2007 10:40:14 +Subject: RE: [Repeater-Builder] Re: Icom gives 5 more D-Star repeaters to the WIA Explaining the continued lack of interest in those specific repeaters.. Personally the conversion process of a junker IS the journey To: [EMAIL PROTECTED]: [EMAIL PROTECTED]: Sat, 24 Nov 2007 10:20:27 +Subject: [Repeater-Builder] Re: Icom gives 5 more D-Star repeaters to the WIA --- In Repeater-Builder@yahoogroups.com, Mark Thompson [EMAIL PROTECTED] wrote: Icom gives 5 more D-Star repeaters to the WIA . Let's see, iCOM gives away repeaters that can only be used with iCOMradios. Join Lavalife for free. What are you waiting for? _ Envoie un sourire, fais rire, amuse-toi! Employez-le maintenant! http://www.emoticonesgratuites.ca/?icid=EMFRCA120
RE: [Repeater-Builder] Re: Repeater Antenna Choice
Hi all we have been using here Sinclair SRL-210 a4 for many years ,they are well built,4 dipoles . they have been cloned by many telecom compagny as Comprod too we have tested Fiberglass antenna,after a time the coating of the fibreglass dissapear and the fiber of the fiberglass broke due to salted winds,we prefer metal antenna since then to bad i have one in my garage,srl210,which i dont used for many years 73/s all gervais http://www.emoticonesgratuites.ca/?icid=EMFRCA120
[Repeater-Builder] 6m Repeater with Tait T800 Series 1 or 2
Has anyone tried to convert T800 's to 6m? I believe there should be a chance with the TX T826 and RX T825. They normally provide 66-88MHz. Thank's for you answers in advance! regards Joerg - OE6VHF
[Repeater-Builder] Re: 2x RX's or 2x TX's on one Controller Port
It's not strange at all, that's how most Groups are configured. But those of us who read through the web interface do not see the attachments, because Yahoo does not retain them. If you upload them they become a part of the archive and everyone has access to them. Some groups do not allow attachments at all, perhaps to encourage uploading to the Group. Regards, Jeff --- In Repeater-Builder@yahoogroups.com, Jim Brown [EMAIL PROTECTED] wrote: Well, strangely enough, when I got my message back, the schematic was attached. I got Bob's schematic attachment also. Take another look at the original message and see if it is not attached, if you still have it. Guess it is in the archives in any case. 73 - Jim W5ZIT --- Jeff Kincaid [EMAIL PROTECTED] wrote: Hi Jim, How 'bout posting your circuit to the Group's file or picture area so we all can enjoy it? Jeff --- In Repeater-Builder@yahoogroups.com, Jim Brown w5zit@ wrote: Kevin, here is a circuit that I have used several times to combine a control receiver with the main receiver in a repeater controller. It can be used to provide a second frequency port to a repeater system with one port having precidence over the other, ie when one port has a signal, the other port is inhibited. I am sending this message direct since I don't think that the Yahoo groups can include an attachment. The circuit is for a positive going COS or RUS signal input, and provides DC isolation for direct connection to a discriminator output. De-emphasis is provided by adding the caps indicated when discriminator audio is used. It has also been used with an NHRC-4 to provide a third port. I use the fan output to control the transmitter PTT on the third port and parallel the audio to both transmitters. The fan output can be disabled to shut off the transmit on the third port. The second port receiver always has precedence over the third port, and both the second and third ports can be disabled by disabling the second port in the NHRC-4 and shutting off the fan control. I hope this is what you were looking for - 73 - Jim W5ZIT --- Kevin Natalia sparcnz@ wrote: Hi All, I am looking for a simple circuit that I could use to connect either 2x RX's or 2x TX's onto 1 port of my controller. Reason, I am dealing with a split site repeater. So I don't want to waste a port for half a system, that I could use for another use. I was then thinking about using the linking port to run the radio as required, and include a switch to switch in or out the radio. I am using a Link Comm RLC-3 controller, ports are nearly all filled up, that's why I am trying to save the port. Radio A (Link) RX --- Radio A (Link) TX | | |-Input to controller / Output from Controller | from site 1 from site 2 | Radio B (1/2 split) RX--X--- X- Radio B (1/2 split) TX X = switch to switch out the Split site repeater. Can I ask for some views on this, and any circuit/s that may help, even if I only get the audio lines working, this would be a help. Regards Kevin. Get Skype and call me for free. Get easy, one-click access to your favorites. Make Yahoo! your homepage. http://www.yahoo.com/r/hs Be a better sports nut! Let your teams follow you with Yahoo Mobile. Try it now. http://mobile.yahoo.com/sports;_ylt=At9_qDKvtAbMuh1G1SQtBI7ntAcJ
[Repeater-Builder] New file uploaded to Repeater-Builder
Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the Repeater-Builder group. File: /Combiner.jpg Uploaded by : w5zit [EMAIL PROTECTED] Description : Combine two audio signals to one input port You can access this file at the URL: http://groups.yahoo.com/group/Repeater-Builder/files/Combiner.jpg To learn more about file sharing for your group, please visit: http://help.yahoo.com/help/us/groups/files Regards, w5zit [EMAIL PROTECTED]
RE: [Repeater-Builder] 19 rack positioning question
Just remember heat rises so the hottest items usually go high in the stack , assuming you have a top mounted fan. To: Repeater-Builder@yahoogroups.com From: [EMAIL PROTECTED] Date: Sat, 24 Nov 2007 18:50:41 + Subject: [Repeater-Builder] 19 rack positioning question In the sprit of the only stupid question is the one that goes un- asked. Here goes: I have a Micor UHF repeater mounted in a 46 x 19 cabinet. It is now a ham band repeater that I have added a new NHRC-5 controller and IRLP interface. The modules are mounted as follows: Top: Custom built 12V PA cooling fan rack controlled by the NHRC-5 aligned with the top door vents. 75W PA Transmitter/ Antenna Network Control module (mostly empty now replaced with NHRC-5 and mods from this site) Receiver module Massive TPN1110B power supply 4 space Bottom: WaCom duplexer cannisters (4) I would like to put the power supply on the bottom so that it aligns with the vents in the cabinet doors and I can add some fans to cool the transformer (you can cook a grilled cheeze sandwitch on it) An added plus is that it will make the cabinet more stable with the weight on the bottom. Is there any issues mounting the duplexers between the receiver and the power supply with the powersupply on the bottom. I hate to move things around and have problems. And yes I will get help to lower the power supply and save some digits. I know the best solution is to replace the powersupply with a more modern one. I plan to do this when funds are better. When this time comes who makes the best replacement powersupply unit? (ok two Questions) Thanks gang Bill N5ZTW _ It's simple! Sell your car for just $30 at CarPoint.com.au http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Fsecure%2Dau%2Eimrworldwide%2Ecom%2Fcgi%2Dbin%2Fa%2Fci%5F450304%2Fet%5F2%2Fcg%5F801459%2Fpi%5F1004813%2Fai%5F859641_t=762955845_r=tig_OCT07_m=EXT
RE: [Repeater-Builder] 19 rack positioning question
Barry, With all due respect, I think the appropriate response to your statement is: Not necessarily. The typical Motorola Micor 100 watt repeater station will have the duplexer at the very bottom of the cabinet, with the power supply just above it. Then follows the unified chassis, and finally the 100 watt PA at the top. While your desire for cooling fans is well-intended, I daresay that the vast majority of 100 watt Micor stations- many of which remain in service today- are cooled solely by convection, and they seem to survive without fans. Let us keep in mind that fans do not cool anything; they simply move air around. If the ambient temperature in an uncooled transmitter shack is 120 degrees Fahrenheit, the fan will simply raise the temperature inside the cabinet to 120 degrees F- which might be higher than the temperature inside the cabinet if no fans were used. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Barry C' Sent: Saturday, November 24, 2007 3:37 PM To: repeater-builder@yahoogroups.com Subject: RE: [Repeater-Builder] 19 rack positioning question Just remember heat rises so the hottest items usually go high in the stack , assuming you have a top mounted fan. To: Repeater-Builder@yahoogroups.com From: [EMAIL PROTECTED] Date: Sat, 24 Nov 2007 18:50:41 + Subject: [Repeater-Builder] 19 rack positioning question In the sprit of the only stupid question is the one that goes un- asked. Here goes: I have a Micor UHF repeater mounted in a 46 x 19 cabinet. It is now a ham band repeater that I have added a new NHRC-5 controller and IRLP interface. The modules are mounted as follows: Top: Custom built 12V PA cooling fan rack controlled by the NHRC-5 aligned with the top door vents. 75W PA Transmitter/ Antenna Network Control module (mostly empty now replaced with NHRC-5 and mods from this site) Receiver module Massive TPN1110B power supply 4 space Bottom: WaCom duplexer cannisters (4) I would like to put the power supply on the bottom so that it aligns with the vents in the cabinet doors and I can add some fans to cool the transformer (you can cook a grilled cheeze sandwitch on it) An added plus is that it will make the cabinet more stable with the weight on the bottom. Is there any issues mounting the duplexers between the receiver and the power supply with the powersupply on the bottom. I hate to move things around and have problems. And yes I will get help to lower the power supply and save some digits. I know the best solution is to replace the powersupply with a more modern one. I plan to do this when funds are better. When this time comes who makes the best replacement powersupply unit? (ok two Questions) Thanks gang Bill N5ZTW Sell your car for just $30 at CarPoint.com.au. It's simple! http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Fsecure%2Dau%2Eimrworldwide% 2Ecom%2Fcgi%2Dbin%2Fa%2Fci%5F450304%2Fet%5F2%2Fcg%5F801459%2Fpi%5F1004813%2F ai%5F859641_t=762955845_r=tig_OCT07_m=EXT
Re: [Repeater-Builder] 19 rack positioning question
Hi Barry, My 2 cents! A 100 watt Micor lofts along regardless of temp. If you can stand it, so can a Micor. Not all of us have 72 degree air conditioned, clean rooms! If your PA has the BIG heatsink, its continuous duty, the mobile heatsink need some cooling because they are only rated at 35 watts tops! Before starting this into my Micor horror stories, I have had 100 watt V's and U's Micor in building penthouses where it was more than +130 degrees, and one in a grain silo -15 degrees below zero with 3 ft of ice in the lowest level. My biggest concern in the hot house was not dripping sweat on the radio. There was a thread here a few years back about your favorite varmint found living or otherwise in your radio cabinet! I have tried to follow the pictures in the Moto manuals, Duplexers on the bottom, PA's on top. 73, Brian, WD9HSY Your kid may be an Honor Student, Your Kid may be a Great Athlete, Your Kid may be a Doctor or a Lawyer, But My kid is in the US Air Force plays with ICBM's, Inter Continental Ballistic Missiles, And what was your Lat/Long? **Check out AOL's list of 2007's hottest products. (http://money.aol.com/special/hot-products-2007?NCID=aoltop000301)
Re: [Repeater-Builder] 19 rack positioning question
On Sat, 24 Nov 2007, TGundo 2003 wrote: My only input is that heat rises, and the heat of the PS will rise and keep the duplexer warm. I would be concerned that the heating of the duplexer (and likely cooling at off-peak times or climate change) would cause the metallic parts in the duplexer to expand and contract possibly throwing it out of tune. maybe a longshot, but the possibility would be enough for me to mount the duplexer farther away, or below the heat sources, or make sure you have some sort of cooling buffer below it. One thing to keep in mind is that crystal ovens use a simlar technique to minimize varitations in frequency. The crystal is held at a temperature far above ambient (about 170 degrees) with a controlled series of heaters. Since the temperature doesn't vary much, the crystal output drifts less as well, compared to a crystal allowed to drift with room temperature, or mounted in the trunk of a car. So keeping the duplexers at a higher temperature year round may actually minimize drift, if you have a means to control it reasonably. -- Kris Kirby, KE4AHR [EMAIL PROTECTED] But remember, with no superpowers comes no responsibility. --rly
RE: [Repeater-Builder] 19 rack positioning question
In my industry we also use rack mounting which is quite the reverse , with fan forced air flow to move the heat so in my experience I stick by the comments .Frankly having just installed a 3000 va ups here recently I prefer it being off the floor anyway . To: Repeater-Builder@yahoogroups.com From: [EMAIL PROTECTED] Date: Sat, 24 Nov 2007 16:14:59 -0800 Subject: RE: [Repeater-Builder] 19 rack positioning question Barry, With all due respect, I think the appropriate response to your statement is: Not necessarily. The typical Motorola Micor 100 watt repeater station will have the duplexer at the very bottom of the cabinet, with the power supply just above it. Then follows the unified chassis, and finally the 100 watt PA at the top. While your desire for cooling fans is well-intended, I daresay that the vast majority of 100 watt Micor stations- many of which remain in service today- are cooled solely by convection, and they seem to survive without fans. Let us keep in mind that fans do not cool anything; they simply move air around. If the ambient temperature in an uncooled transmitter shack is 120 degrees Fahrenheit, the fan will simply raise the temperature inside the cabinet to 120 degrees F- which might be higher than the temperature inside the cabinet if no fans were used. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Barry C' Sent: Saturday, November 24, 2007 3:37 PM To: repeater-builder@yahoogroups.com Subject: RE: [Repeater-Builder] 19 rack positioning question Just remember heat rises so the hottest items usually go high in the stack , assuming you have a top mounted fan. To: Repeater-Builder@yahoogroups.com From: [EMAIL PROTECTED] Date: Sat, 24 Nov 2007 18:50:41 + Subject: [Repeater-Builder] 19 rack positioning question In the sprit of the only stupid question is the one that goes un- asked. Here goes: I have a Micor UHF repeater mounted in a 46 x 19 cabinet. It is now a ham band repeater that I have added a new NHRC-5 controller and IRLP interface. The modules are mounted as follows: Top: Custom built 12V PA cooling fan rack controlled by the NHRC-5 aligned with the top door vents. 75W PA Transmitter/ Antenna Network Control module (mostly empty now replaced with NHRC-5 and mods from this site) Receiver module Massive TPN1110B power supply 4 space Bottom: WaCom duplexer cannisters (4) I would like to put the power supply on the bottom so that it aligns with the vents in the cabinet doors and I can add some fans to cool the transformer (you can cook a grilled cheeze sandwitch on it) An added plus is that it will make the cabinet more stable with the weight on the bottom. Is there any issues mounting the duplexers between the receiver and the power supply with the powersupply on the bottom. I hate to move things around and have problems. And yes I will get help to lower the power supply and save some digits. I know the best solution is to replace the powersupply with a more modern one. I plan to do this when funds are better. When this time comes who makes the best replacement powersupply unit? (ok two Questions) Thanks gang Bill N5ZTW Sell your car for just $30 at CarPoint.com.au. It's simple! http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Fsecure%2Dau%2Eimrworldwide% 2Ecom%2Fcgi%2Dbin%2Fa%2Fci%5F450304%2Fet%5F2%2Fcg%5F801459%2Fpi%5F1004813%2F ai%5F859641_t=762955845_r=tig_OCT07_m=EXT _ New music from the Rogue Traders - listen now! http://ninemsn.com.au/share/redir/adTrack.asp?mode=clickclientID=832referral=hotmailtaglineOct07URL=http://music.ninemsn.com.au/roguetraders
Re: [Repeater-Builder] 19 rack positioning question
I mount heavy stuff at the bottom of the rack, lighter stuff working upwards. Heat rise is incidental to my overall systems, those components are designed to take it. Yes, fans move the ambient temperature around. In the grand scheme of things, it has never been an issue for me. VHF duplexers and cavities are rarely mounted in the same rack as the transmitters due to size alone. Barry C' wrote: In my industry we also use rack mounting which is quite the reverse , with fan forced air flow to move the heat so in my experience I stick by the comments .Frankly having just installed a 3000 va ups here recently I prefer it being off the floor anyway . To: Repeater-Builder@yahoogroups.com From: [EMAIL PROTECTED] Date: Sat, 24 Nov 2007 16:14:59 -0800 Subject: RE: [Repeater-Builder] 19 rack positioning question Barry, With all due respect, I think the appropriate response to your statement is: Not necessarily. The typical Motorola Micor 100 watt repeater station will have the duplexer at the very bottom of the cabinet, with the power supply just above it. Then follows the unified chassis, and finally the 100 watt PA at the top. While your desire for cooling fans is well-intended, I daresay that the vast majority of 100 watt Micor stations- many of which remain in service today- are cooled solely by convection, and they seem to survive without fans. Let us keep in mind that fans do not cool anything; they simply move air around. If the ambient temperature in an uncooled transmitter shack is 120 degrees Fahrenheit, the fan will simply raise the temperature inside the cabinet to 120 degrees F- which might be higher than the temperature inside the cabinet if no fans were used. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Barry C' Sent: Saturday, November 24, 2007 3:37 PM To: repeater-builder@yahoogroups.com Subject: RE: [Repeater-Builder] 19 rack positioning question Just remember heat rises so the hottest items usually go high in the stack , assuming you have a top mounted fan. To: Repeater-Builder@yahoogroups.com From: [EMAIL PROTECTED] Date: Sat, 24 Nov 2007 18:50:41 + Subject: [Repeater-Builder] 19 rack positioning question In the sprit of the only stupid question is the one that goes un- asked. Here goes: I have a Micor UHF repeater mounted in a 46 x 19 cabinet. It is now a ham band repeater that I have added a new NHRC-5 controller and IRLP interface. The modules are mounted as follows: Top: Custom built 12V PA cooling fan rack controlled by the NHRC-5 aligned with the top door vents. 75W PA Transmitter/ Antenna Network Control module (mostly empty now replaced with NHRC-5 and mods from this site) Receiver module Massive TPN1110B power supply 4 space Bottom: WaCom duplexer cannisters (4) I would like to put the power supply on the bottom so that it aligns with the vents in the cabinet doors and I can add some fans to cool the transformer (you can cook a grilled cheeze sandwitch on it) An added plus is that it will make the cabinet more stable with the weight on the bottom. Is there any issues mounting the duplexers between the receiver and the power supply with the powersupply on the bottom. I hate to move things around and have problems. And yes I will get help to lower the power supply and save some digits. I know the best solution is to replace the powersupply with a more modern one. I plan to do this when funds are better. When this time comes who makes the best replacement powersupply unit? (ok two Questions) Thanks gang Bill N5ZTW Sell your car for just $30 at CarPoint.com.au. It's simple! http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Fsecure%2Dau%2Eimrworldwide% 2Ecom%2Fcgi%2Dbin%2Fa%2Fci%5F450304%2Fet%5F2%2Fcg%5F801459%2Fpi%5F1004813%2F ai%5F859641_t=762955845_r=tig_OCT07_m=EXT _ New music from the Rogue Traders - listen now! http://ninemsn.com.au/share/redir/adTrack.asp?mode=clickclientID=832referral=hotmailtaglineOct07URL=http://music.ninemsn.com.au/roguetraders
RE: [Repeater-Builder] 19 rack positioning question
I put a VHF repeater together this summer in a Stromberg Carlson cabinet that the phone company retired and had to install a fan in the top of the cabinet to get the heat removed. The cabinet was insulated with one inch foam on top, bottom, sides and doors. It was a side-by-side rack cabnet with 19 inch rack on one side and 26 inch rack on the other. By adding some 2 inch spacers to extend the rack rails forward, a GE Mastr II repeater fit on the 19 inch side, and by removing the 26 inch rack rails, the duplexer fit into the other side of the cabinet. There were places for two exhaust blowers in the top of the cabinet with a flapper to close off the blower hole when it was not energized. The air entered the cabinet directly under the 19 inch rack side, with an RFI screen covering the hole and an air filter to clean any debris out of the incoming air. The whole thing sits up about 2 feet off the ground, so it is real handy to get at the equipment. The 19 inch rack side hinges out and access to the rear of the repeater is excellent. The GE power supply is on the bottom, with the controller above it and the repeater at the top of the rack. I originally mounted the 50 deg C (about 105 F) thermal switch on the power amp heat sink, but found the temp got too high in the cabinet before the fan came on. By mounting the thermal switch to the top plate of the power supply, I got the best temperature control. I only used one exhaust blower as the flapper keeps the other hole sealed. On a warm sunny day at 7000 ft, the temp inside the cabinet rose to an uncomfortable 120 degrees (80 deg outside) until the fan was installed. With the fan controlled by the thermal switch on top of the power supply, the temp felt as cool inside the cabinet as outside the cabinet. I should mention that this is an outdoor cabinet and is sealed completely to keep any water out. All entry points for wiring and coax are on the bottom of the cabinet. Exhaust air is into a pleneum at the top of the cabined with a screened outlet across the front. The GE power supply has vent holes in the bottom, which wound up being directly above the 1 foot square vent hole in the bottom of the cabinet, so as soon as the fan comes on, outside air is brought directly into and around the power supply. I plugged the entry hole in the other side of the cabinet with a piece of plywood, and the duplexer sits above it, so no outside air necessary there. It took a crane to get this cabinet installed on the concrete footers we poured, as it weighs about 1500 # with the equipment installed. There are a number of pictures of this installation if anyone is interested: http://sbarcnm.org/CamelotInstallThumbnails.html 73 - Jim W5ZIT --- Eric Lemmon [EMAIL PROTECTED] wrote: Barry, With all due respect, I think the appropriate response to your statement is: Not necessarily. The typical Motorola Micor 100 watt repeater station will have the duplexer at the very bottom of the cabinet, with the power supply just above it. Then follows the unified chassis, and finally the 100 watt PA at the top. While your desire for cooling fans is well-intended, I daresay that the vast majority of 100 watt Micor stations- many of which remain in service today- are cooled solely by convection, and they seem to survive without fans. Let us keep in mind that fans do not cool anything; they simply move air around. If the ambient temperature in an uncooled transmitter shack is 120 degrees Fahrenheit, the fan will simply raise the temperature inside the cabinet to 120 degrees F- which might be higher than the temperature inside the cabinet if no fans were used. 73, Eric Lemmon WB6FLY Be a better pen pal. Text or chat with friends inside Yahoo! Mail. See how. http://overview.mail.yahoo.com/
RE: [Repeater-Builder] 19 rack positioning question
Very familiar with these , wonderfully well made and will outlast all of us although in my part of the world they have fans Std . To: Repeater-Builder@yahoogroups.com From: [EMAIL PROTECTED] Date: Sat, 24 Nov 2007 19:39:45 -0800 Subject: RE: [Repeater-Builder] 19 rack positioning question I put a VHF repeater together this summer in a Stromberg Carlson cabinet that the phone company retired and had to install a fan in the top of the cabinet to get the heat removed. The cabinet was insulated with one inch foam on top, bottom, sides and doors. It was a side-by-side rack cabnet with 19 inch rack on one side and 26 inch rack on the other. By adding some 2 inch spacers to extend the rack rails forward, a GE Mastr II repeater fit on the 19 inch side, and by removing the 26 inch rack rails, the duplexer fit into the other side of the cabinet. There were places for two exhaust blowers in the top of the cabinet with a flapper to close off the blower hole when it was not energized. The air entered the cabinet directly under the 19 inch rack side, with an RFI screen covering the hole and an air filter to clean any debris out of the incoming air. The whole thing sits up about 2 feet off the ground, so it is real handy to get at the equipment. The 19 inch rack side hinges out and access to the rear of the repeater is excellent. The GE power supply is on the bottom, with the controller above it and the repeater at the top of the rack. I originally mounted the 50 deg C (about 105 F) thermal switch on the power amp heat sink, but found the temp got too high in the cabinet before the fan came on. By mounting the thermal switch to the top plate of the power supply, I got the best temperature control. I only used one exhaust blower as the flapper keeps the other hole sealed. On a warm sunny day at 7000 ft, the temp inside the cabinet rose to an uncomfortable 120 degrees (80 deg outside) until the fan was installed. With the fan controlled by the thermal switch on top of the power supply, the temp felt as cool inside the cabinet as outside the cabinet. I should mention that this is an outdoor cabinet and is sealed completely to keep any water out. All entry points for wiring and coax are on the bottom of the cabinet. Exhaust air is into a pleneum at the top of the cabined with a screened outlet across the front. The GE power supply has vent holes in the bottom, which wound up being directly above the 1 foot square vent hole in the bottom of the cabinet, so as soon as the fan comes on, outside air is brought directly into and around the power supply. I plugged the entry hole in the other side of the cabinet with a piece of plywood, and the duplexer sits above it, so no outside air necessary there. It took a crane to get this cabinet installed on the concrete footers we poured, as it weighs about 1500 # with the equipment installed. There are a number of pictures of this installation if anyone is interested: http://sbarcnm.org/CamelotInstallThumbnails.html 73 - Jim W5ZIT --- Eric Lemmon [EMAIL PROTECTED] wrote: Barry, With all due respect, I think the appropriate response to your statement is: Not necessarily. The typical Motorola Micor 100 watt repeater station will have the duplexer at the very bottom of the cabinet, with the power supply just above it. Then follows the unified chassis, and finally the 100 watt PA at the top. While your desire for cooling fans is well-intended, I daresay that the vast majority of 100 watt Micor stations- many of which remain in service today- are cooled solely by convection, and they seem to survive without fans. Let us keep in mind that fans do not cool anything; they simply move air around. If the ambient temperature in an uncooled transmitter shack is 120 degrees Fahrenheit, the fan will simply raise the temperature inside the cabinet to 120 degrees F- which might be higher than the temperature inside the cabinet if no fans were used. 73, Eric Lemmon WB6FLY __ Be a better pen pal. Text or chat with friends inside Yahoo! Mail. See how. http://overview.mail.yahoo.com/ _ Overpaid or Underpaid? Check our comprehensive Salary Centre http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Fcontent%2Emycareer%2Ecom%2Eau%2Fsalary%2Dcentre%3Fs%5Fcid%3D595810_t=766724125_r=Hotmail_Email_Tagline_MyCareer_Oct07_m=EXT
RE: [Repeater-Builder] 19 rack positioning question
I agree. This rack had the mounting for the fans, but they had been stripped out by the time it made it to us. The hard part was figuring out just what dimension fan would fit - 73 - Jim W5ZIT --- Barry C' [EMAIL PROTECTED] wrote: Very familiar with these , wonderfully well made and will outlast all of us although in my part of the world they have fans Std . Be a better pen pal. Text or chat with friends inside Yahoo! Mail. See how. http://overview.mail.yahoo.com/
