Re: [Repeater-Builder] Mastr II mods and parts
Thank you for your help. I appreciate it! I've put a couple of questions inline below. On Sat, Jan 2, 2010 at 4:18 PM, Kevin Custer kug...@kuggie.com wrote: Michael Cox wrote: I justed purchased a GE MAST II UHF repeater that has a 450-460 split (see it at http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemitem=230415711221ssPageName=STRK:MEWNX:IT ) I need to get a power adapter, a CWID, You mean a Power Amplifier or simply called a PA. You're right. Thx. For a CWID, I recommend a real repeater controller. and, depening on the price, a duplexer. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. I'd like to modify this to use on either a GMRS repeater or a 40cm ham band. This will be my first repeater. I think you meant 70 cm ham band... Modification is easy, as no RF mods need made for either use. You just need to make it duplex. Information on www.mastr2.com will help you there. Yes, I did mean 70 cm. :) I'm assuming that I could get this http://www.repeater-builder.com/products/ampbd.html for the power adapter. You could, but I'd just buy the right PA. They are on eBay all the time. http://cgi.ebay.com/GE-Ericsson-VHF-Mastr-II-Master-Repeater-100watt-amp_W0QQitemZ260529220211QQcmdZViewItemQQptZ2_Way_Radios_FRS?hash=item3ca8c06a73 Are these what I'm looking for? It looks liek there is a UHF and a VHF version of the PA. Is that correct? Are they not compatible with each other? http://cgi.ebay.com/GE-Ericsson-VHF-Mastr-II-Master-Repeater-100watt-amp_W0QQitemZ260529220211QQcmdZViewItemQQptZ2_Way_Radios_FRS?hash=item3ca8c06a73 http://cgi.ebay.com/GE-Ma-COM-100-watt-amplifier-20-watt-input-MASTR-II_W0QQitemZ200422213614QQcmdZViewItemQQptZ2_Way_Radios_FRS?hash=item2eaa1847ee http://cgi.ebay.com/GE-MASTR-II-100-WATT-AMPLIFIER-VHF_W0QQitemZ140370861181QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item20aec15c7d http://cgi.ebay.com/GE-Ericsson-Mastr-II-Repeater-Cabinet-Console-45W-PA_W0QQitemZ300382163124QQcmdZViewItemQQptZ2_Way_Radios_FRS?hash=item45f02c10b4 Do you have any recommendations for the duplexer and CWID? Duplexer - used WACOM Products WP-678 (or similar), also available from eBay. I couldn't find any on eBay. Any guesses what I'd be paying for something like this? Controller - I recommend a NHRC model that plugs into the Systems board, or, one of the Pion Simon models that plug into the card cage. http://www.nhrc.net/ge-stuff.php http://www.pionsimon.com/products.htm It looks like I can use the NHRC-4/M2 to make it a linked repeater. If I go with the Ham repeater, I'll most likely do that. That would require, if I understand correctly, another radio connected in, so that will have to be done later with future funds. :) If I decide to make it a GMRS repeater, I won't have to worry about that and will go with the PSE508-2, as its a little less expensive. Good luck, Kevin Custer -- --- Michael H. Cox michaelh...@gmail.com
[Repeater-Builder] Moto amp conversion
Has anyone had any success converting a Motorola Micor TLB1413C amplifier to 6 meters. I know the C is 36-42 Mhz split but I have one available. Any help would be appreciated. Charles, NM4V
[Repeater-Builder] Audio Mixer for multiple repeaters
Hi everyone , Happy new year! We are a club looking for an audio mixer that can mix up to 3 or 4 repeaters with different impedance, we are hooking up 3 different repeaters together. We built an homemade audio mixer but not very stable , we hope to find something solid and well shielded because there are lots of interference at that specific site. Any ideas where we could get such thing pre built or built ? Thank you
Re: [Repeater-Builder] Mastr II mods and parts
Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case. The determining factor usually ends up being the length and size of feed-line necessary to get from the repeater to the antenna. On UHF, unless the feed-line length is really short, you'll want to use some type of hard-line cable. The cost of this cable, depending on type and length, can be costly. It may be less costly to use one antenna and a duplexer then to install two antennas and have two runs of feed-line. In addition, you'll usually end up with a better balanced system using one antenna because using two can cause a disparity if both antennas don't have the exact same pattern - which could be difficult to achieve depending on the tower space available. In installations where you have to pay rent on tower space - it's usually by far cheaper to purchase a duplexer. RE: Power Amplifier Are these what I'm looking for? Generically - Yes. It looks like there is a UHF and a VHF version of the PA. Is that correct? Yes. Are they not compatible with each other? No. VHF and UHF are two totally different bands. You cannot use a UHF PA on a VHF repeater and vice-versa. The third one you listed is a Mobile PA - not something you'll want. You want a UHF Station PA like the second one you listed - but it isn't the exact one either. The one you want requires 200 mW of drive - not 20 watts - but, the correct one looks very similar to the one in your number two listing. I don't presently see a good candidate on eBay - but they show up all the time. Duplexer - used WACOM Products WP-678 (or similar), also available from eBay. I couldn't find any on eBay. Any guesses what I'd be paying for something like this? $250 plus shipping. Controller - I recommend a NHRC model that plugs into the Systems board, or, one of the Pion Simon models that plug into the card cage. http://www.nhrc.net/ge-stuff.php http://www.pionsimon.com/products.htm It looks like I can use the NHRC-4/M2 to make it a linked repeater. If I go with the Ham repeater, I'll most likely do that. That would require, if I understand correctly, another radio connected in, so that will have to be done later with future funds. :) Correct. If I decide to make it a GMRS repeater, I won't have to worry about that and will go with the PSE508-2, as its a little less expensive. Also a good choice. Kevin
[Repeater-Builder] Re: Audio Mixer for multiple repeaters
Re: Audio Mixer for multiple repeaters I know it wouldn't at first glance be considered a mixer... but using an LDG Voter as a mixer (and voter) works out very well. http://www.ldgelectronics.com/c/252/products/5/19/1 If you don't need as many inputs, consider the CAT Auto RLS-1000B. http://www.catauto.com/rls1000.html And of course many repeater controllers are multi-port boxes. s. adjiqc adj...@... wrote: Hi everyone , Happy new year! We are a club looking for an audio mixer that can mix up to 3 or 4 repeaters with different impedance, we are hooking up 3 different repeaters together. We built an homemade audio mixer but not very stable , we hope to find something solid and well shielded because there are lots of interference at that specific site. Any ideas where we could get such thing pre built or built ? Thank you
Re: [Repeater-Builder] Mastr II mods and parts
For fun we operated a 400 watt erp repeater with two antennas and no duplexer. We were able to achieve about 100db attenuation by using the roof equipment penthouse. The transmit antenna was mounted on the top of the penthouse and the receive antenna was installed diagonally from the transmit antenna on the roof below the penthouse. Each antenna was physically separated by the penthouse structure. Transmit performance was good and receiver performance was good about 270 degrees minus the abstructed zone. No feedback or other issues. Eventually, we installed TXRX 6 can duplexer and utilized the penthouse antenna. Receive coverage regained 360 degree coverage. So, it is doable if you have the right antenna site. Best, dave wa3gin - Original Message - From: Kevin Custer To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 11:12 AM Subject: Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case. The determining factor usually ends up being the length and size of feed-line necessary to get from the repeater to the antenna. On UHF, unless the feed-line length is really short, you'll want to use some type of hard-line cable. The cost of this cable, depending on type and length, can be costly. It may be less costly to use one antenna and a duplexer then to install two antennas and have two runs of feed-line. In addition, you'll usually end up with a better balanced system using one antenna because using two can cause a disparity if both antennas don't have the exact same pattern - which could be difficult to achieve depending on the tower space available. In installations where you have to pay rent on tower space - it's usually by far cheaper to purchase a duplexer. RE: Power Amplifier Are these what I'm looking for? Generically - Yes. It looks like there is a UHF and a VHF version of the PA. Is that correct? Yes. Are they not compatible with each other? No. VHF and UHF are two totally different bands. You cannot use a UHF PA on a VHF repeater and vice-versa. The third one you listed is a Mobile PA - not something you'll want. You want a UHF Station PA like the second one you listed - but it isn't the exact one either. The one you want requires 200 mW of drive - not 20 watts - but, the correct one looks very similar to the one in your number two listing. I don't presently see a good candidate on eBay - but they show up all the time. Duplexer - used WACOM Products WP-678 (or similar), also available from eBay. I couldn't find any on eBay. Any guesses what I'd be paying for something like this? $250 plus shipping. Controller - I recommend a NHRC model that plugs into the Systems board, or, one of the Pion Simon models that plug into the card cage. http://www.nhrc.net/ge-stuff.php http://www.pionsimon.com/products.htm It looks like I can use the NHRC-4/M2 to make it a linked repeater. If I go with the Ham repeater, I'll most likely do that. That would require, if I understand correctly, another radio connected in, so that will have to be done later with future funds. :) Correct. If I decide to make it a GMRS repeater, I won't have to worry about that and will go with the PSE508-2, as its a little less expensive. Also a good choice. Kevin
Re: [Repeater-Builder] Mastr II mods and parts
Kevin mentioned feedline, but didn't mention to stay away from LMR or 9913 type foil/shield combinations in duplex service. Chuck WB2EDV - Original Message - From: Kevin Custer To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 11:12 AM Subject: Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case.
Re: [Repeater-Builder] Mastr II mods and parts
I believe the issues with LMR were resolved years ago Chuck. Can you refresh the group on some of the primary issues? Thanks, dave p.s. we've been using it for five years at ten sites with no problems. - Original Message - From: Chuck Kelsey To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 12:48 PM Subject: Re: [Repeater-Builder] Mastr II mods and parts Kevin mentioned feedline, but didn't mention to stay away from LMR or 9913 type foil/shield combinations in duplex service. Chuck WB2EDV - Original Message - From: Kevin Custer To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 11:12 AM Subject: Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case.
RE: [Repeater-Builder] Mastr II mods and parts
A local group here in Florida just replaced their feed line to their antenna with LMR 400 coax this past weekend. I cringed after I heard that they had done this. But, am I now hearing that the use of LMR 400 is no longer taboo? - thanks.. - Mike From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of WA3GIN Sent: Sunday, January 03, 2010 1:35 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts I believe the issues with LMR were resolved years ago Chuck. Can you refresh the group on some of the primary issues? Thanks, dave p.s. we've been using it for five years at ten sites with no problems. - Original Message - From: Chuck Kelsey mailto:wb2...@roadrunner.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 12:48 PM Subject: Re: [Repeater-Builder] Mastr II mods and parts Kevin mentioned feedline, but didn't mention to stay away from LMR or 9913 type foil/shield combinations in duplex service. Chuck WB2EDV - Original Message - From: Kevin Custer mailto:kug...@kuggie.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 11:12 AM Subject: Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case. __ Information from ESET NOD32 Antivirus, version of virus signature database 4740 (20100103) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
Re: [Repeater-Builder] Mastr II mods and parts
Yes, it was resolved at a lot of commercial sites by not allowing it to be used ;-) Usually after a bit of time, the cable will start to become a source of noise as the two dissimilar metals start to react with each other. There are many documented cases of this problem. Search this group's messages and you'll see this has been discussed over and over. It comes up about every other week. The manufacturers do not list these cables for low PIM. There's info on the Repeater Builder site here: http://www.repeater-builder.com/antenna/pdf/recommended-coax-and-connectors-for-iden.pdf Personally, I've seen it cause problems on several sites. Getting it out of service solved the problem. Chuck WB2EDV - Original Message - From: WA3GIN To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 1:34 PM Subject: Re: [Repeater-Builder] Mastr II mods and parts I believe the issues with LMR were resolved years ago Chuck. Can you refresh the group on some of the primary issues? Thanks, dave p.s. we've been using it for five years at ten sites with no problems.
Re: [Repeater-Builder] Mastr II mods and parts
At least when it starts causing noise, you'll know where to look. It may take a while, or it could happen pretty soon. Like with anything, some people have managed to dodge the bullet for quite some time. I've seen nothing official that says the problem was resolved. Chuck WB2EDV - Original Message - From: Michael Ryan To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 1:41 PM Subject: RE: [Repeater-Builder] Mastr II mods and parts A local group here in Florida just replaced their feed line to their antenna with LMR 400 coax this past weekend. I cringed after I heard that they had done this. But, am I now hearing that the use of LMR 400 is no longer taboo? - thanks.. - Mike From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of WA3GIN Sent: Sunday, January 03, 2010 1:35 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts I believe the issues with LMR were resolved years ago Chuck. Can you refresh the group on some of the primary issues? Thanks, dave p.s. we've been using it for five years at ten sites with no problems. - Original Message - From: Chuck Kelsey To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 12:48 PM Subject: Re: [Repeater-Builder] Mastr II mods and parts Kevin mentioned feedline, but didn't mention to stay away from LMR or 9913 type foil/shield combinations in duplex service. Chuck WB2EDV - Original Message - From: Kevin Custer To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 11:12 AM Subject: Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case. __ Information from ESET NOD32 Antivirus, version of virus signature database 4740 (20100103) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -- No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.725 / Virus Database: 270.14.124/2597 - Release Date: 01/02/10 03:22:00
Re: [Repeater-Builder] Mastr II mods and parts
Didn't the CEO or someone of similar heft at Times Microwave have a letter in QST a while back stating the entire LMR series wasn't designed for PIM performance, referring potential repeater-use customers to their line of low-PIM cables? No luck on a wildcard search on the ARRL site... Go figure. On Sun, Jan 3, 2010 at 12:18 PM, Chuck Kelsey wb2...@roadrunner.com wrote: At least when it starts causing noise, you'll know where to look. It may take a while, or it could happen pretty soon. Like with anything, some people have managed to dodge the bullet for quite some time. I've seen nothing official that says the problem was resolved. Chuck WB2EDV - Original Message - *From:* Michael Ryan mryan...@tampabay.rr.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Sunday, January 03, 2010 1:41 PM *Subject:* RE: [Repeater-Builder] Mastr II mods and parts A local group here in Florida just replaced their feed line to their antenna with LMR 400 coax this past weekend. I cringed after I heard that they had done this. But, am I now hearing that the use of LMR 400 is no longer taboo? – thanks…. - Mike *From:* Repeater-Builder@yahoogroups.com [mailto: repeater-buil...@yahoogroups.com] *On Behalf Of *WA3GIN *Sent:* Sunday, January 03, 2010 1:35 PM *To:* Repeater-Builder@yahoogroups.com *Subject:* Re: [Repeater-Builder] Mastr II mods and parts I believe the issues with LMR were resolved years ago Chuck. Can you refresh the group on some of the primary issues? Thanks, dave p.s. we've been using it for five years at ten sites with no problems. - Original Message - *From:* Chuck Kelsey wb2...@roadrunner.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Sunday, January 03, 2010 12:48 PM *Subject:* Re: [Repeater-Builder] Mastr II mods and parts Kevin mentioned feedline, but didn't mention to stay away from LMR or 9913 type foil/shield combinations in duplex service. Chuck WB2EDV - Original Message - *From:* Kevin Custer kug...@kuggie.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Sunday, January 03, 2010 11:12 AM *Subject:* Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case. __ Information from ESET NOD32 Antivirus, version of virus signature database 4740 (20100103) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -- No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.725 / Virus Database: 270.14.124/2597 - Release Date: 01/02/10 03:22:00
Re: [Repeater-Builder] Mastr II mods and parts
Yes, it said that in the article. However, the article went on to say that some of the ham dealers sold it for duplex service all the time, so the writer concluded (somehow) that it was OK to use. Go figure. Chuck WB2EDV - Original Message - From: AJ To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 2:17 PM Subject: Re: [Repeater-Builder] Mastr II mods and parts Didn't the CEO or someone of similar heft at Times Microwave have a letter in QST a while back stating the entire LMR series wasn't designed for PIM performance, referring potential repeater-use customers to their line of low-PIM cables? No luck on a wildcard search on the ARRL site... Go figure. On Sun, Jan 3, 2010 at 12:18 PM, Chuck Kelsey wb2...@roadrunner.com wrote: At least when it starts causing noise, you'll know where to look. It may take a while, or it could happen pretty soon. Like with anything, some people have managed to dodge the bullet for quite some time. I've seen nothing official that says the problem was resolved. Chuck WB2EDV
[Repeater-Builder] Re: Audio Mixer for multiple repeaters
If you are just mixing audio, a cheap mixing board for music applications works well. http://www.zzounds.com/item--BEHMX400 -or- http://www.zzounds.com/item--BEHXENTX802 Behringer is not normally know for it's quality, but some of their items work really well. Here are some higher priced units. http://www.zzounds.com/item--PEVPV6 -or- http://www.zzounds.com/item--MAC402VLZ3 Dwayne Kincaid WD8OYG --- In Repeater-Builder@yahoogroups.com, skipp025 skipp...@... wrote: Re: Audio Mixer for multiple repeaters I know it wouldn't at first glance be considered a mixer... but using an LDG Voter as a mixer (and voter) works out very well. http://www.ldgelectronics.com/c/252/products/5/19/1 If you don't need as many inputs, consider the CAT Auto RLS-1000B. http://www.catauto.com/rls1000.html And of course many repeater controllers are multi-port boxes. s. adjiqc adjiqc@ wrote: Hi everyone , Happy new year! We are a club looking for an audio mixer that can mix up to 3 or 4 repeaters with different impedance, we are hooking up 3 different repeaters together. We built an homemade audio mixer but not very stable , we hope to find something solid and well shielded because there are lots of interference at that specific site. Any ideas where we could get such thing pre built or built ? Thank you
[Repeater-Builder] DB Bp cans to BpBr for duplexers
Hi fellas, I need some input... I have 11, yes 11 DB products Bp cans from various combiners. They are 8 in diameter and have the model #SP8145-VT1 or SP8145-VT2 on some of them. I want to turn them into BpBr cans in order to make duplexers out of them. I think I will need some of those little variable caps or is there another way? Where does one get those caps? I think they are made by johanson or something like that. Has anyone ever tried this? Thanks!!! 73 de N5NPO Norm
Re: [Repeater-Builder] Mastr II mods and parts
At 1/3/2010 11:11, you wrote: Yes, it was resolved at a lot of commercial sites by not allowing it to be used ;-) For me, the resolution came from a Times Microwave sales rep. who admitted that LMR-400 is not appropriate for duplex use. Having said that, you can get away with using it in situations such as temporary/portable repeater installations provided the connectors are installed properly the feedline is not used near the antenna, where RF can couple to the outer braided shield. In no circumstances would I ever use it at a shared comm. site. Usually after a bit of time, the cable will start to become a source of noise as the two dissimilar metals start to react with each other. There are many documented cases of this problem. Search this group's messages and you'll see this has been discussed over and over. It comes up about every other week. BTW, they don't need to be dissemilar metals. I once confirmed a 100% copper braided RG-213 jumper as a PIM source. I only use silver-plated braided coax beyond the duplexer from now on. Bob NO6B
[Repeater-Builder] FS: repeater system stuff individual this time
Hey gang, it's me again. The repeater package didn't sell as a whole so I'll offer the stuff individually. Just make me your best offer on whatever you want. I'm not thrilled about shipping the duplexers but I'll do my best. -- ok, you can look over the pictures from the links below, i'll try to cover it here in text. top to bottom: mastr exec II - this was a uhf combination but has 33 split rx and tx modules. crystalled and tuned to 53.45 tx and 51.75 rx (1.7 meg offset) it has g.e. tone board (big red) in rx only mode on 146.2 better than .3uv rx from the hp 8924c. 42 watts out of the duplexer cabinet. squirrel cage blower on the heatsink fins with circuit connected to the controller. homebrew (by me) power supply - has run and will run 3 100 watt amplifiers or rigs all day long. it has been my primary supply for years. it has 4 35amp bridges and is very heavy duty. it used to run a 6m 100 watt amp, 70cm 100 watt amp, icom 746 @ 100 watts as remote base. tone panel - NOT for sale arcom rc210 repeater controller - this is fairly new. it's the latest hardware version and running 4.74 firmware. ibm thinkpad 760xl - programming the rc210. this DOES go but i've got to take the hard drive or spend an hour cleaning alinco dr-135t - hooked up to the rc210 on port 2. does a great job. I've got the mic, box, manual, mount for this. mini itx computer running centos irlp distro. node 3185. all passwords etc etc passes to buyer. master II 13 split rx drawer. NOT hooked up at present. but has been checked out with said 8924c and works fine. crystalled on 29.600 if i remember correctly. had been connected to aux audio on the rc210. db-4030 duplexer - coils clipped by me and tuned to repeater pair. obviously this notch only 4 can setup doesn't provide desense free isolation. it does work very well @ the 1.7mHz split though. I'll have to find a good size box for this, it's heavy too! sinclair q202g - this set is the higher split for vhf but tuned ok @ 147.045+ 1 can has been opened to reseat the plunger but the 8924c couldn't tell. never got a coordination so there it sits. Pretty heavy so shipping won't be cheap. not in the pictures is a vhf mastr exec II desktop matching the 6m. it has NOT been duplexed or recrystalled. it has been benched and works fine on the stock crystals. also, a uhf mastr exec II desktop that also works but doesn't have the LED clock in it. another vhf mastr exec II desktop. a 13 split mastr II mobile a mastr exec II mobile i think a 33 split but could be an 88. i didn't dig it out. 1 accessory group for an exec II mobile. 1 accessory group for a mastr II mobile. i'm in Salem, Missouri. that is 30 minutes south of Rolla, Missouri. that is on i-44 halfway between sprinfield missouri and st. louis missouri. Payment via paypal is preferred. (so much easier to print the shipping label for ups) i appreciate the bandwith and hope this pile can help someone or their club out. chris kb0wlf
Re: [Repeater-Builder] Mastr II mods and parts
Very interesting...all our sites are dense with RF from Public Safety radio systems 800, 700, VHF, etc. No problems in five years. I suspect it has more to do with how the RF connections are made than the LMR cable. Just my subjective opinion of one. 73, dave wa3gin - Original Message - From: n...@no6b.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 2:45 PM Subject: Re: [Repeater-Builder] Mastr II mods and parts At 1/3/2010 11:11, you wrote: Yes, it was resolved at a lot of commercial sites by not allowing it to be used ;-) For me, the resolution came from a Times Microwave sales rep. who admitted that LMR-400 is not appropriate for duplex use. Having said that, you can get away with using it in situations such as temporary/portable repeater installations provided the connectors are installed properly the feedline is not used near the antenna, where RF can couple to the outer braided shield. In no circumstances would I ever use it at a shared comm. site. Usually after a bit of time, the cable will start to become a source of noise as the two dissimilar metals start to react with each other. There are many documented cases of this problem. Search this group's messages and you'll see this has been discussed over and over. It comes up about every other week. BTW, they don't need to be dissemilar metals. I once confirmed a 100% copper braided RG-213 jumper as a PIM source. I only use silver-plated braided coax beyond the duplexer from now on. Bob NO6B
Re: [Repeater-Builder] DB Bp cans to BpBr for duplexers
Havent opened on of the dB cans, but if it is like these sinclairs I have, Replace the ground lug on the coupling loop with a Johansen cap. For VHF you will need the 1-20 caps or 1-30pF. For 220 and UHF use the 2-10pF. This has to do with the split, for me it is about 8pF for the notch to appear on the high side and 16pF for the other on VHF. Remove the opposite loop and replace with a metal plate or a hole plug. Johansens can be obtained from RF Parts, Surplus Sales of Nebraska or Ebay. Just be sure the cap you get will fit, I just got a whole bunch of Russian Johansen clones that are about triple the volume, but won't fit in the can. On Sun, Jan 3, 2010 at 12:43 PM, NORM KNAPP nkn...@twowayradio.net wrote: Hi fellas, I need some input... I have 11, yes 11 DB products Bp cans from various combiners. They are 8 in diameter and have the model #SP8145-VT1 or SP8145-VT2 on some of them. I want to turn them into BpBr cans in order to make duplexers out of them. I think I will need some of those little variable caps or is there another way? Where does one get those caps? I think they are made by johanson or something like that. Has anyone ever tried this? Thanks!!! 73 de N5NPO Norm Yahoo! Groups Links
Re: [Repeater-Builder] DB Bp cans to BpBr for duplexers
Also you may wish to try building dual loop BpBr as described here http://www.repeater-builder.com/antenna/pdf/ve2azx-duplexerinfo.pdf Takes more connectors and tees, but you don't have to modify the original cavity. On Sun, Jan 3, 2010 at 1:06 PM, DCFluX dcf...@gmail.com wrote: Havent opened on of the dB cans, but if it is like these sinclairs I have, Replace the ground lug on the coupling loop with a Johansen cap. For VHF you will need the 1-20 caps or 1-30pF. For 220 and UHF use the 2-10pF. This has to do with the split, for me it is about 8pF for the notch to appear on the high side and 16pF for the other on VHF. Remove the opposite loop and replace with a metal plate or a hole plug. Johansens can be obtained from RF Parts, Surplus Sales of Nebraska or Ebay. Just be sure the cap you get will fit, I just got a whole bunch of Russian Johansen clones that are about triple the volume, but won't fit in the can. On Sun, Jan 3, 2010 at 12:43 PM, NORM KNAPP nkn...@twowayradio.net wrote: Hi fellas, I need some input... I have 11, yes 11 DB products Bp cans from various combiners. They are 8 in diameter and have the model #SP8145-VT1 or SP8145-VT2 on some of them. I want to turn them into BpBr cans in order to make duplexers out of them. I think I will need some of those little variable caps or is there another way? Where does one get those caps? I think they are made by johanson or something like that. Has anyone ever tried this? Thanks!!! 73 de N5NPO Norm Yahoo! Groups Links
RE: [Repeater-Builder] Mastr II mods and parts
Very interesting...all our sites are dense with RF from Public Safety radio systems 800, 700, VHF, etc. No problems in five years. I suspect it has more to do with how the RF connections are made than the LMR cable. Just my subjective opinion of one. Actually it is the cable. My discussion with two engineers at TimesMicrowave indicated that it was not so much the dissimilar metals that were the issue, but the foil over braid and two somewhat independent shields. No mention was made of this being a termination or connection issue. As with everything, Your Mileage May Vary. I use the stuff in non duplex telemetry applications by the 1000 roll, not a problem. We have some on site in use for non duplex applications, but many well engineered public safety sites will not allow the product on site regardless of the use. My personal preference is a 100% copper shield obtained with any of the smaller superflexible Andrews and other products. I try to use ¼, 3/8 and ½ superflex for those duplexer to the radio and duplexer to the lighting arrestor runs. IMHO, nothing says 100% shielded like solid copper. 73 Daron N7HQR
[Repeater-Builder] Re: 220 repeater
Yes, that's one of them. Darn thing only ran for 30 years before it broke. :) 'JK --- In Repeater-Builder@yahoogroups.com, n...@... wrote: At 1/2/2010 13:20, you wrote: G.E. pre-Prog. 'JK Is that 224.660 W6GAA on PV? Can't key it this evening. Bob NO6B
Re: [Repeater-Builder] Mastr II mods and parts
Yes, I agree. Various plated connectors can also be a problem. Unfortunately most antenna manufacturers don't use silver plated coax in their pigtails and harnesses. Chuck WB2EDV - Original Message - From: n...@no6b.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 2:45 PM Subject: Re: [Repeater-Builder] Mastr II mods and parts At 1/3/2010 11:11, you wrote: Yes, it was resolved at a lot of commercial sites by not allowing it to be used ;-) For me, the resolution came from a Times Microwave sales rep. who admitted that LMR-400 is not appropriate for duplex use. Having said that, you can get away with using it in situations such as temporary/portable repeater installations provided the connectors are installed properly the feedline is not used near the antenna, where RF can couple to the outer braided shield. In no circumstances would I ever use it at a shared comm. site. Usually after a bit of time, the cable will start to become a source of noise as the two dissimilar metals start to react with each other. There are many documented cases of this problem. Search this group's messages and you'll see this has been discussed over and over. It comes up about every other week. BTW, they don't need to be dissemilar metals. I once confirmed a 100% copper braided RG-213 jumper as a PIM source. I only use silver-plated braided coax beyond the duplexer from now on. Bob NO6B Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.725 / Virus Database: 270.14.124/2597 - Release Date: 01/02/10 03:22:00
[Repeater-Builder] Cold temps and repeaters
Down here in Florida this week we are ENJOYING somewhat of a cold wave. Today's high around Tampa about 45 degrees. A bit unusual. My repeater on 224 mhz is having a fit today. Sounds like some kind of a mix getting in, sometimes not strong enough to open the squelch, sometimes it will creep in after the repeater is keyed either by the id'er or someone keying the machine and tripping the cor. My machine is not out in the elements but is also not in a particularly climate controlled location, inside a warehouse. Can the below nom temps be creating some issues with the nearby environment and some equipment elsewhere or is it more likely that something is 'chilly' in my own rack? - Mike
Re: [Repeater-Builder] Cold temps and repeaters
I've seen it happen. Changes in temperature can affect the stability of a transmitter causing it to spur. Intermod sources can come and go with weather changes as well. It's 12 chilly degrees here in western New York and the snow has been heavy all day. 45 would be a heat wave ;-) Chuck WB2EDV - Original Message - From: Michael Ryan To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 3:45 PM Subject: [Repeater-Builder] Cold temps and repeaters Down here in Florida this week we are ENJOYING somewhat of a cold wave. Today's high around Tampa about 45 degrees. A bit unusual. My repeater on 224 mhz is having a fit today. Sounds like some kind of a mix getting in, sometimes not strong enough to open the squelch, sometimes it will creep in after the repeater is keyed either by the id'er or someone keying the machine and tripping the cor. My machine is not out in the elements but is also not in a particularly climate controlled location, inside a warehouse. Can the below nom temps be creating some issues with the nearby environment and some equipment elsewhere or is it more likely that something is 'chilly' in my own rack? - Mike __ Information from ESET NOD32 Antivirus, version of virus signature database 4740 (20100103) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -- No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.725 / Virus Database: 270.14.124/2597 - Release Date: 01/02/10 03:22:00
RE: [Repeater-Builder] Cold temps and repeaters
Mike, The first question that comes to mind is, what is the make and model of your repeater? Some repeaters have better low-temperature performance than others, especially when fully-compensated channel elements are used. Perhaps the duplexer is affected by the temperature, although 45 degrees is hardly an extreme. It may be worthwhile to install a simple thermostat-controlled resistive heater inside the cabinet. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Michael Ryan Sent: Sunday, January 03, 2010 12:45 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Cold temps and repeaters Down here in Florida this week we are ENJOYING somewhat of a cold wave. Today's high around Tampa about 45 degrees. A bit unusual. My repeater on 224 MHz is having a fit today. Sounds like some kind of a mix getting in, sometimes not strong enough to open the squelch, sometimes it will creep in after the repeater is keyed either by the id'er or someone keying the machine and tripping the cor. My machine is not out in the elements but is also not in a particularly climate controlled location, inside a warehouse. Can the below nom temps be creating some issues with the nearby environment and some equipment elsewhere or is it more likely that something is 'chilly' in my own rack? - Mike
Re: [Repeater-Builder] Cold temps and repeaters
Our local vhf machine experienced a loosening squelch and verhy long tail with extremely low temps (-30f). A slight tweak on the squelch solved the issue. Its in an unheated environment. Sent on the TELUS Mobility network with BlackBerry -Original Message- From: Eric Lemmon wb6...@verizon.net Date: Sun, 03 Jan 2010 13:01:26 To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Cold temps and repeaters Mike, The first question that comes to mind is, what is the make and model of your repeater? Some repeaters have better low-temperature performance than others, especially when fully-compensated channel elements are used. Perhaps the duplexer is affected by the temperature, although 45 degrees is hardly an extreme. It may be worthwhile to install a simple thermostat-controlled resistive heater inside the cabinet. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Michael Ryan Sent: Sunday, January 03, 2010 12:45 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Cold temps and repeaters Down here in Florida this week we are ENJOYING somewhat of a cold wave. Today's high around Tampa about 45 degrees. A bit unusual. My repeater on 224 MHz is having a fit today. Sounds like some kind of a mix getting in, sometimes not strong enough to open the squelch, sometimes it will creep in after the repeater is keyed either by the id'er or someone keying the machine and tripping the cor. My machine is not out in the elements but is also not in a particularly climate controlled location, inside a warehouse. Can the below nom temps be creating some issues with the nearby environment and some equipment elsewhere or is it more likely that something is 'chilly' in my own rack? - Mike
RE: [Repeater-Builder] Cold temps and repeaters
I plan to run over tonight and put a drop light in the rack with a 100 or 150 watt light bulb to put off some heat. I might also tighten up the squelch a frog hair. The repeater is a RANGER unit with a Neutec transceiver on 220. The duplexer is 4 Telwave cans. - Mike From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Eric Lemmon Sent: Sunday, January 03, 2010 4:01 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Cold temps and repeaters Mike, The first question that comes to mind is, what is the make and model of your repeater? Some repeaters have better low-temperature performance than others, especially when fully-compensated channel elements are used. Perhaps the duplexer is affected by the temperature, although 45 degrees is hardly an extreme. It may be worthwhile to install a simple thermostat-controlled resistive heater inside the cabinet. 73, Eric Lemmon WB6FLY -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 Michael Ryan Sent: Sunday, January 03, 2010 12:45 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] Cold temps and repeaters Down here in Florida this week we are ENJOYING somewhat of a cold wave. Today's high around Tampa about 45 degrees. A bit unusual. My repeater on 224 MHz is having a fit today. Sounds like some kind of a mix getting in, sometimes not strong enough to open the squelch, sometimes it will creep in after the repeater is keyed either by the id'er or someone keying the machine and tripping the cor. My machine is not out in the elements but is also not in a particularly climate controlled location, inside a warehouse. Can the below nom temps be creating some issues with the nearby environment and some equipment elsewhere or is it more likely that something is 'chilly' in my own rack? - Mike __ Information from ESET NOD32 Antivirus, version of virus signature database 4740 (20100103) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
RE: [Repeater-Builder] Cold temps and repeaters
Did you say 12 degrees? My freezer doesn't get that cold.they open the homeless shelters down here when it gets much below 50 degrees. I will add some heat inside the rack tonight and stir. - Mike From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Sunday, January 03, 2010 3:59 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Cold temps and repeaters I've seen it happen. Changes in temperature can affect the stability of a transmitter causing it to spur. Intermod sources can come and go with weather changes as well. It's 12 chilly degrees here in western New York and the snow has been heavy all day. 45 would be a heat wave ;-) Chuck WB2EDV - Original Message - From: Michael Ryan mailto:mryan...@tampabay.rr.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 3:45 PM Subject: [Repeater-Builder] Cold temps and repeaters Down here in Florida this week we are ENJOYING somewhat of a cold wave. Today's high around Tampa about 45 degrees. A bit unusual. My repeater on 224 mhz is having a fit today. Sounds like some kind of a mix getting in, sometimes not strong enough to open the squelch, sometimes it will creep in after the repeater is keyed either by the id'er or someone keying the machine and tripping the cor. My machine is not out in the elements but is also not in a particularly climate controlled location, inside a warehouse. Can the below nom temps be creating some issues with the nearby environment and some equipment elsewhere or is it more likely that something is 'chilly' in my own rack? - Mike __ Information from ESET NOD32 Antivirus, version of virus signature database 4740 (20100103) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com _ No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.725 / Virus Database: 270.14.124/2597 - Release Date: 01/02/10 03:22:00 __ Information from ESET NOD32 Antivirus, version of virus signature database 4740 (20100103) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
Re: [Repeater-Builder] Mastr II mods and parts
At 1/3/2010 12:16, you wrote: Yes, I agree. Various plated connectors can also be a problem. Unfortunately most antenna manufacturers don't use silver plated coax in their pigtails and harnesses. This is probably why all Cushcraft 4-pole antennas eventually cause desense to the systems they're connected to. I have one in use for a TX-only link. Someday I'll take it down replace that harness with RG142 or RG214. Bob NO6B
Re: [Repeater-Builder] Mastr II mods and parts
Well Cushcraft what can I say? I never saw one I liked. Gamma matches make pretty poor performers in my opinion. I don't believe any of the Decibel line over the years used anything but standard copper braid on any of their antennas. My thought is that while the copper braid may occasionally cause PIM, it's most likely very rare. The foil/braid combo is another story. Chuck - Original Message - From: n...@no6b.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 3:50 PM Subject: Re: [Repeater-Builder] Mastr II mods and parts At 1/3/2010 12:16, you wrote: Yes, I agree. Various plated connectors can also be a problem. Unfortunately most antenna manufacturers don't use silver plated coax in their pigtails and harnesses. This is probably why all Cushcraft 4-pole antennas eventually cause desense to the systems they're connected to. I have one in use for a TX-only link. Someday I'll take it down replace that harness with RG142 or RG214. Bob NO6B Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.725 / Virus Database: 270.14.124/2597 - Release Date: 01/02/10 03:22:00
[Repeater-Builder] Micor 12W PA Modification
The recent discussion about converting a Micor 2W UHF station to 12W by modifying the TLE1893B Antenna Network is a rehash of the same topic that was discussed on R-B back in May 2004. One of the key points made was that the voltage representing reflected power is scaled differently in the 12W TLE1670B antenna network, than it is in the 2W TLE1893B network. Bypassing the attenuator changes the forward power to 12W, but failure to add the four components may leave the power control module- and possibly the PA as well- vulnerable to damage from reflected power. The two capacitors and the one resistor that must be added are easy; the identification of thermistor RT602 is not. Is there any reader of this list who can identify this thermistor by its part number and its characteristics? I, too, have a 2W Micor repeater that I'd like to convert to 12W, so I would appreciate some information about a commercial device that matches the original Motorola part. 73, Eric Lemmon WB6FLY
[Repeater-Builder] duplexer tuning uk please
hello looking for someone to tune some duplexers for me couple of vhf and a uhf will pay what ever i need to and cover postage costs for return, licenced supplier and will send copys of licences if required thank you phill bridlington east yorkshire
Re: [Repeater-Builder] duplexer tuning uk please
Phil; Check with KA1RCI, Steve (st...@ka1rci ) He bought a couple of sets of 220 mc. duplexers from me and retuned them to our band. He has all the equipment. Clay W 8 J V V - Original Message - From: phillmobile To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 17 08 Subject: [Repeater-Builder] duplexer tuning uk please hello looking for someone to tune some duplexers for me couple of vhf and a uhf will pay what ever i need to and cover postage costs for return, licenced supplier and will send copys of licences if required thank you phill bridlington east yorkshire
Re: [Repeater-Builder] Re: Audio Mixer for multiple repeaters
Hi Skipp025, How would this handle the core and the PTT adio and would it be easy to match the impedance from all the repeaters ? Thanks for thr info. GV From: skipp025 skipp...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Sun, January 3, 2010 11:25:50 AM Subject: [Repeater-Builder] Re: Audio Mixer for multiple repeaters Re: Audio Mixer for multiple repeaters I know it wouldn't at first glance be considered a mixer... but using an LDG Voter as a mixer (and voter) works out very well. http://www.ldgelect ronics.com/ c/252/products/ 5/19/1 If you don't need as many inputs, consider the CAT Auto RLS-1000B. http://www.catauto. com/rls1000. html And of course many repeater controllers are multi-port boxes. s. adjiqc adj...@... wrote: Hi everyone , Happy new year! We are a club looking for an audio mixer that can mix up to 3 or 4 repeaters with different impedance, we are hooking up 3 different repeaters together. We built an homemade audio mixer but not very stable , we hope to find something solid and well shielded because there are lots of interference at that specific site. Any ideas where we could get such thing pre built or built ? Thank you __ Be smarter than spam. See how smart SpamGuard is at giving junk email the boot with the All-new Yahoo! Mail. Click on Options in Mail and switch to New Mail today or register for free at http://mail.yahoo.ca
[Repeater-Builder] Re: 220 repeater
To follow up on Roger's 13-509 story, we built one also in the mid 70's and has been in continuous service in the Dallas area since, along with a pair of home built 224-JJ antennas (DB called them a 244 back then) - no duplexer (easy to do when you are on a 1500' tower). The radios may be hard to find but ask around, someone probably has a unit sitting in a closet. Mike/W5JR 1.1. Re: 220 repeater Posted by: w5rdwrwhitete...@verizon.net w5rdw Date: Sat Jan 2, 2010 5:23 am ((PST)) If you are interested in building it youself, a modified Clegg FM-76 or Midland 13-509 transceiver (xtal controlled rigs) can be modified very easily into a 220 repeater. I have done a number of repeaters like this, the first one in the late 1970's, into a very nice 10 watt repeater with a receiver that can't be beat as far as sensitivity is concerned. Very simple and reliable. Numerous articles on this modification are available on the web. Also available is the Maggiore repeaters line fromhttp://www.hiprorepeaters.com I have one of these on 224.18 MHz in Dallas and it has been trouble free many, many years. I have up at 350 ft. a dB224JJ antenna (no longer made) from dB Products (out of business, but a nice antenna). 73, Roger White W5RDW Murphy, Texas
[Repeater-Builder] Cold MVP
Well speaking of cold we have a MVP remote RX which is a duplexed 2 meter rx to 70 cm tx that is in a elevator room on top of a 15 story building and that room is largly at near ambient temperature and now with the cold seems slow to come up. The elements were temp compensated etc and I really don't think that it is coming up off frequency. If anything it seems it there at extremely low power but not confirmed at this point. The site is in a secure site so is hard to get access to for testing. What thoughts does anyone have on this. Randy
RE: [Repeater-Builder] Cold MVP
Randy, I am surprised that your building inspector allowed your repeater to be installed at that location. Article 620.37(A) of the National Electrical Code forbids any equipment or wiring not directly associated with the elevator to be installed in elevator control rooms or machinery spaces. In my area, a paging company installed a paging transmitter in the elevator control room at a hospital, but was ordered to remove it when the building inspector made a routine walk-through. Ironically, that paging system was installed to support the hospital's own doctor paging system! Since the hospital is the tallest building in the city, the management had another masonry room installed on the roof, with a separate entrance, specifically to contain radio equipment. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Randy Sent: Sunday, January 03, 2010 4:38 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Cold MVP Well speaking of cold we have a MVP remote RX which is a duplexed 2 meter rx to 70 cm tx that is in a elevator room on top of a 15 story building and that room is largely at near ambient temperature and now with the cold seems slow to come up. The elements were temp compensated etc and I really don't think that it is coming up off frequency. If anything it seems it there at extremely low power but not confirmed at this point. The site is in a secure site so is hard to get access to for testing. What thoughts does anyone have on this. Randy
Re: [Repeater-Builder] Cold MVP
Interesting note about that article. I used to do maintenance on a couple stations that were located in an elevator control room at a hospital in NW wash DC. I wounder now if they have been moved? It was a very erie place to work on a station when one of the elevators would start running. -Richard From: Eric Lemmon wb6...@verizon.net To: Repeater-Builder@yahoogroups.com Sent: Sun, January 3, 2010 8:26:41 PM Subject: RE: [Repeater-Builder] Cold MVP Randy, I am surprised that your building inspector allowed your repeater to be installed at that location. Article 620.37(A) of the National Electrical Code forbids any equipment or wiring not directly associated with the elevator to be installed in elevator control rooms or machinery spaces. In my area, a paging company installed a paging transmitter in the elevator control room at a hospital, but was ordered to remove it when the building inspector made a routine walk-through. Ironically, that paging system was installed to support the hospital's own doctor paging system! Since the hospital is the tallest building in the city, the management had another masonry room installed on the roof, with a separate entrance, specifically to contain radio equipment. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@ yahoogroups. com [mailto:Repeater-Builder@ yahoogroups. com] On Behalf Of Randy Sent: Sunday, January 03, 2010 4:38 PM To: Repeater-Builder@ yahoogroups. com Subject: [Repeater-Builder] Cold MVP Well speaking of cold we have a MVP remote RX which is a duplexed 2 meter rx to 70 cm tx that is in a elevator room on top of a 15 story building and that room is largely at near ambient temperature and now with the cold seems slow to come up. The elements were temp compensated etc and I really don't think that it is coming up off frequency. If anything it seems it there at extremely low power but not confirmed at this point. The site is in a secure site so is hard to get access to for testing. What thoughts does anyone have on this. Randy
Re: [Repeater-Builder] Cold MVP
At 1/3/2010 04:37 PM, you wrote: Well speaking of cold we have a MVP remote RX which is a duplexed 2 meter rx to 70 cm tx that is in a elevator room on top of a 15 story building and that room is largly at near ambient temperature and now with the cold seems slow to come up. The elements were temp compensated etc and I really don't think that it is coming up off frequency. If anything it seems it there at extremely low power but not confirmed at this point. The site is in a secure site so is hard to get access to for testing. What thoughts does anyone have on this. If you have the power turned down on it (such as for driving an external RFPA), the power level will drop with colder ambient temperature, but will eventually come back up if the TX is kept on for a while. I have 2 on a mountaintop site (0 to 100 °F ambient): one duplex link one repeater. The repeater radio runs at full power I never have any power issues with it. The link is set to around 3-4 watts, when it gets well below freezing it takes a couple of seconds for the TX to make enough power to establish the link. Bob NO6B
[Repeater-Builder] Re: Cold MVP
Well Eric, I guess I am not sure if it really qualifys as the elevator room or not as I beleive that is a story below. Only time anyone has been there is when we installed it. Therefore it has been a long time since I have been there, as the need hasn't happened. Since a trip that requires such work to get too we have avoided going less absolutely needed too. So guess I can't say it is or isn't in the elevator area and guess there has been no complaints maybe it is Ok. In any case I am not sure this problem will even evoke a trip as it is only in the extreme cold and it is only one site of three available, albeit it is as good one. Randy --- In Repeater-Builder@yahoogroups.com, Eric Lemmon wb6...@... wrote: Randy, I am surprised that your building inspector allowed your repeater to be installed at that location. Article 620.37(A) of the National Electrical Code forbids any equipment or wiring not directly associated with the elevator to be installed in elevator control rooms or machinery spaces. In my area, a paging company installed a paging transmitter in the elevator control room at a hospital, but was ordered to remove it when the building inspector made a routine walk-through. Ironically, that paging system was installed to support the hospital's own doctor paging system! Since the hospital is the tallest building in the city, the management had another masonry room installed on the roof, with a separate entrance, specifically to contain radio equipment. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Randy Sent: Sunday, January 03, 2010 4:38 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Cold MVP Well speaking of cold we have a MVP remote RX which is a duplexed 2 meter rx to 70 cm tx that is in a elevator room on top of a 15 story building and that room is largely at near ambient temperature and now with the cold seems slow to come up. The elements were temp compensated etc and I really don't think that it is coming up off frequency. If anything it seems it there at extremely low power but not confirmed at this point. The site is in a secure site so is hard to get access to for testing. What thoughts does anyone have on this. Randy
[Repeater-Builder] Re: Cold MVP
Well you might have hit the nail on the head. It is turned down to about 3-4 watts as that was all we needed to make the path. I only noticed this last winter and this one now but guess it could have been like that from the beginning without us noticing it. Next time I have one to test I will put it in the freezer and test that. I was thinking maybe the relay or the COR switch might be not switching. The radio was made to take it better than the controller. Randy If you have the power turned down on it (such as for driving an external RFPA), the power level will drop with colder ambient temperature, but will eventually come back up if the TX is kept on for a while. I have 2 on a mountaintop site (0 to 100 °F ambient): one duplex link one repeater. The repeater radio runs at full power I never have any power issues with it. The link is set to around 3-4 watts, when it gets well below freezing it takes a couple of seconds for the TX to make enough power to establish the link. Bob NO6B
[Repeater-Builder] Re: MSR2000 Power Supply part needed
Thanks, George, for the chart. Today I put the board on the bench and applied power as noted in the manual for bench testing. First thing I tested was the reference voltage and lo and behold it was wandering around (light bulb above head begins to glow!). Close inspection of the ref voltage components revealed a dark discoloration of the board and a general corroded look to the solder connections. Looks very much like cold solder joints. The rest of the board connections are all shiny. (bulb is getting brighter) Also the tinning on some of the PC traces was etched down to copper. A few minutes work with an acid brush and some alcohol cleaned up the gunk on the board and the joints were all touched up with a soldering iron. (Bulb fully on!) It has been running on the bench for 5 hours and the reference voltage hasn't budged from 6.5v !! I will install the card back in the power supply this week and see if our voltage problem goes away, and it carries the repeater load. Interestingly enough our initial indications of a problem was when the repeater would drop off the air . We thought the problem was with the PA, since we could still see some drive coming out of the exciter. Eventually it completely failed, but not until after we replaced the PA only to see the same problem come back. Oh well, we now have a spare PA! As the NTSB would put it: Probable Cause - corrosion of solder connections due to caustic substance. To put it plainly - mouse droppings/pee! We had the same thing happen to an RC-850 controller a few years ago that nearly killed the board. The repeater is in an unheated building in a field away from other structures (it is a microwave tower that the Navy lets us use), so the mice seem to like the warmth. Next project is to make a mouse shield for the repeater box! I'll let you know how it turns out. We are hoping for K3HKI = 1, Mice = 0 73 de Tom/W4OKW Pax River George Henry wrote: Attached is the troubleshooting chart for that PS... maybe it will be of some help. - Original Message - From: Tom Clarke w4...@md.metrocast.net To: ka3...@att.net Sent: Saturday, January 02, 2010 10:25 PM Subject: Re: MSR2000 Power Supply part needed Hi George, Thanks for the tip. We already tried that with no joy. R7 just moves the voltage +/- .5v or so around 8.5 so the problem is probably upstream. We also are not getting the 9.3v on Tx, but that may be related to the 14 v reg problem. I need to go back and look at the 9.4v reg also to see if it is working OK. I have looked at the reg card and don't see any obvious crispy critters! 73 Tom/W4OKW near DC
Re: [Repeater-Builder] Cold temps and repeaters
I remember the 146.79 repeater in Henrietta (Rochester) NY back in the mid/late 70's It was housed in an old 'fridge in a shed in the middle of a farm field, at the base of the tower. IIRC, it had a fan to cool it in the summer, and a 25-watt light buld to keep it warm in the winter. KISS at it's best. George, KA3HSW / WQGJ413 - Original Message - From: Chuck Kelsey wb2...@roadrunner.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 2:58 PM Subject: Re: [Repeater-Builder] Cold temps and repeaters I've seen it happen. Changes in temperature can affect the stability of a transmitter causing it to spur. Intermod sources can come and go with weather changes as well. It's 12 chilly degrees here in western New York and the snow has been heavy all day. 45 would be a heat wave ;-) Chuck WB2EDV
Re: [Repeater-Builder] Mastr II mods and parts
Will this Duplexer work with the Mastr II repeater? http://cgi.ebay.com/UHF-50W-6-CAVITY-DUPLEXER-FOR-REPEATER-FREE-TUNING_W0QQitemZ350300447727QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item518f88a3ef On Sun, Jan 3, 2010 at 9:32 AM, WA3GIN wa3...@comcast.net wrote: For fun we operated a 400 watt erp repeater with two antennas and no duplexer. We were able to achieve about 100db attenuation by using the roof equipment penthouse. The transmit antenna was mounted on the top of the penthouse and the receive antenna was installed diagonally from the transmit antenna on the roof below the penthouse. Each antenna was physically separated by the penthouse structure. Transmit performance was good and receiver performance was good about 270 degrees minus the abstructed zone. No feedback or other issues. Eventually, we installed TXRX 6 can duplexer and utilized the penthouse antenna. Receive coverage regained 360 degree coverage. So, it is doable if you have the right antenna site. Best, dave wa3gin - Original Message - *From:* Kevin Custer kug...@kuggie.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Sunday, January 03, 2010 11:12 AM *Subject:* Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case. The determining factor usually ends up being the length and size of feed-line necessary to get from the repeater to the antenna. On UHF, unless the feed-line length is really short, you'll want to use some type of hard-line cable. The cost of this cable, depending on type and length, can be costly. It may be less costly to use one antenna and a duplexer then to install two antennas and have two runs of feed-line. In addition, you'll usually end up with a better balanced system using one antenna because using two can cause a disparity if both antennas don't have the exact same pattern - which could be difficult to achieve depending on the tower space available. In installations where you have to pay rent on tower space - it's usually by far cheaper to purchase a duplexer. RE: Power Amplifier Are these what I'm looking for? Generically - Yes. It looks like there is a UHF and a VHF version of the PA. Is that correct? Yes. Are they not compatible with each other? No. VHF and UHF are two totally different bands. You cannot use a UHF PA on a VHF repeater and vice-versa. The third one you listed is a Mobile PA - not something you'll want. You want a UHF Station PA like the second one you listed - but it isn't the exact one either. The one you want requires 200 mW of drive - not 20 watts - but, the correct one looks very similar to the one in your number two listing. I don't presently see a good candidate on eBay - but they show up all the time. Duplexer - used WACOM Products WP-678 (or similar), also available from eBay. I couldn't find any on eBay. Any guesses what I'd be paying for something like this? $250 plus shipping. Controller - I recommend a NHRC model that plugs into the Systems board, or, one of the Pion Simon models that plug into the card cage. http://www.nhrc.net/ge-stuff.php http://www.pionsimon.com/products.htm It looks like I can use the NHRC-4/M2 to make it a linked repeater. If I go with the Ham repeater, I'll most likely do that. That would require, if I understand correctly, another radio connected in, so that will have to be done later with future funds. :) Correct. If I decide to make it a GMRS repeater, I won't have to worry about that and will go with the PSE508-2, as its a little less expensive. Also a good choice. Kevin -- --- Michael H. Cox michaelh...@gmail.com
[Repeater-Builder] Re: Mastr II mods and parts
I totally agree with that Bob. I believe the dissimilar metal *thing* has far less to do with generating noise and PIM, than the simple fact that we have separate wires and elements constructing the shield that have very bad electrical connections with each other. Aluminum is known to always form a non-conducting oxide on it when exposed to air. Non-silver plated copper braid wires can have the same problem, though not quite as readily if kept dry. In any case, there are thousands of potential diode mixers per foot of cable. I too, use only silver-plated braid or solid copper such as Superflex. I'll never forget the piece of RG213 that I once had feeding a repeater antenna that easily generated noise when taken in hand and flexed. I say all the good luck to those that successfully use 9913 and similar cables in duplex service. I'll use cables that are virtually certain to *not* generate duplex noise in my installations. Laryn K8TVZ BTW, they don't need to be dissemilar metals. I once confirmed a 100% copper braided RG-213 jumper as a PIM source. I only use silver-plated braided coax beyond the duplexer from now on. Bob NO6B
Re: [Repeater-Builder] Re: Mastr II mods and parts
What cable do you guys recommend? Thanks, Michael H. Cox michaelh...@gmail.com -Original Message- From: larynl2 lar...@hotmail.com Date: Mon, 04 Jan 2010 05:36:20 To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Mastr II mods and parts I totally agree with that Bob. I believe the dissimilar metal *thing* has far less to do with generating noise and PIM, than the simple fact that we have separate wires and elements constructing the shield that have very bad electrical connections with each other. Aluminum is known to always form a non-conducting oxide on it when exposed to air. Non-silver plated copper braid wires can have the same problem, though not quite as readily if kept dry. In any case, there are thousands of potential diode mixers per foot of cable. I too, use only silver-plated braid or solid copper such as Superflex. I'll never forget the piece of RG213 that I once had feeding a repeater antenna that easily generated noise when taken in hand and flexed. I say all the good luck to those that successfully use 9913 and similar cables in duplex service. I'll use cables that are virtually certain to *not* generate duplex noise in my installations. Laryn K8TVZ BTW, they don't need to be dissemilar metals. I once confirmed a 100% copper braided RG-213 jumper as a PIM source. I only use silver-plated braided coax beyond the duplexer from now on. Bob NO6B
[Repeater-Builder] Re: Mastr II mods and parts
For connection between duplexer and radios I like 1/4 Superflex, but RG400 or RG142 is also great. To a duplex antenna for short runs those same cables could be used, keeping loss figures in mind. Otherwise appropriately sized Heliax or equivalent cables should be used. Laryn K8TVZ --- In Repeater-Builder@yahoogroups.com, Michael H. Cox michaelh...@... wrote: What cable do you guys recommend? Thanks,
Re: [Repeater-Builder] Mastr II mods and parts
I would not recommend that duplexer for a repeater. -- Original Message -- Received: Sun, 03 Jan 2010 08:47:16 PM PST From: Michael Cox michaelh...@gmail.com To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts Will this Duplexer work with the Mastr II repeater? http://cgi.ebay.com/UHF-50W-6-CAVITY-DUPLEXER-FOR-REPEATER-FREE-TUNING_W0QQitemZ350300447727QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item518f88a3ef On Sun, Jan 3, 2010 at 9:32 AM, WA3GIN wa3...@comcast.net wrote: For fun we operated a 400 watt erp repeater with two antennas and no duplexer. We were able to achieve about 100db attenuation by using the roof equipment penthouse. The transmit antenna was mounted on the top of the penthouse and the receive antenna was installed diagonally from the transmit antenna on the roof below the penthouse. Each antenna was physically separated by the penthouse structure. Transmit performance was good and receiver performance was good about 270 degrees minus the abstructed zone. No feedback or other issues. Eventually, we installed TXRX 6 can duplexer and utilized the penthouse antenna. Receive coverage regained 360 degree coverage. So, it is doable if you have the right antenna site. Best, dave wa3gin - Original Message - *From:* Kevin Custer kug...@kuggie.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Sunday, January 03, 2010 11:12 AM *Subject:* Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case. The determining factor usually ends up being the length and size of feed-line necessary to get from the repeater to the antenna. On UHF, unless the feed-line length is really short, you'll want to use some type of hard-line cable. The cost of this cable, depending on type and length, can be costly. It may be less costly to use one antenna and a duplexer then to install two antennas and have two runs of feed-line. In addition, you'll usually end up with a better balanced system using one antenna because using two can cause a disparity if both antennas don't have the exact same pattern - which could be difficult to achieve depending on the tower space available. In installations where you have to pay rent on tower space - it's usually by far cheaper to purchase a duplexer. RE: Power Amplifier Are these what I'm looking for? Generically - Yes. It looks like there is a UHF and a VHF version of the PA. Is that correct? Yes. Are they not compatible with each other? No. VHF and UHF are two totally different bands. You cannot use a UHF PA on a VHF repeater and vice-versa. The third one you listed is a Mobile PA - not something you'll want. You want a UHF Station PA like the second one you listed - but it isn't the exact one either. The one you want requires 200 mW of drive - not 20 watts - but, the correct one looks very similar to the one in your number two listing. I don't presently see a good candidate on eBay - but they show up all the time. Duplexer - used WACOM Products WP-678 (or similar), also available from eBay. I couldn't find any on eBay. Any guesses what I'd be paying for something like this? $250 plus shipping. Controller - I recommend a NHRC model that plugs into the Systems board, or, one of the Pion Simon models that plug into the card cage. http://www.nhrc.net/ge-stuff.php http://www.pionsimon.com/products.htm It looks like I can use the NHRC-4/M2 to make it a linked repeater. If I go with the Ham repeater, I'll most likely do that. That would require, if I understand correctly, another radio connected in, so that will have to be done later with future funds. :) Correct. If I decide to make it a GMRS repeater, I won't have to worry about that and will go with the PSE508-2, as its a little less expensive. Also a good choice. Kevin -- --- Michael H. Cox michaelh...@gmail.com
Re: [Repeater-Builder] Mastr II mods and parts
Any reasons? Thanks, Michael H. Cox michaelh...@gmail.com -Original Message- From: JOHN MACKEY jmac...@usa.net Date: Sun, 03 Jan 2010 21:55:33 To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts I would not recommend that duplexer for a repeater. -- Original Message -- Received: Sun, 03 Jan 2010 08:47:16 PM PST From: Michael Cox michaelh...@gmail.com To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts Will this Duplexer work with the Mastr II repeater? http://cgi.ebay.com/UHF-50W-6-CAVITY-DUPLEXER-FOR-REPEATER-FREE-TUNING_W0QQitemZ350300447727QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item518f88a3ef On Sun, Jan 3, 2010 at 9:32 AM, WA3GIN wa3...@comcast.net wrote: For fun we operated a 400 watt erp repeater with two antennas and no duplexer. We were able to achieve about 100db attenuation by using the roof equipment penthouse. The transmit antenna was mounted on the top of the penthouse and the receive antenna was installed diagonally from the transmit antenna on the roof below the penthouse. Each antenna was physically separated by the penthouse structure. Transmit performance was good and receiver performance was good about 270 degrees minus the abstructed zone. No feedback or other issues. Eventually, we installed TXRX 6 can duplexer and utilized the penthouse antenna. Receive coverage regained 360 degree coverage. So, it is doable if you have the right antenna site. Best, dave wa3gin - Original Message - *From:* Kevin Custer kug...@kuggie.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Sunday, January 03, 2010 11:12 AM *Subject:* Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case. The determining factor usually ends up being the length and size of feed-line necessary to get from the repeater to the antenna. On UHF, unless the feed-line length is really short, you'll want to use some type of hard-line cable. The cost of this cable, depending on type and length, can be costly. It may be less costly to use one antenna and a duplexer then to install two antennas and have two runs of feed-line. In addition, you'll usually end up with a better balanced system using one antenna because using two can cause a disparity if both antennas don't have the exact same pattern - which could be difficult to achieve depending on the tower space available. In installations where you have to pay rent on tower space - it's usually by far cheaper to purchase a duplexer. RE: Power Amplifier Are these what I'm looking for? Generically - Yes. It looks like there is a UHF and a VHF version of the PA. Is that correct? Yes. Are they not compatible with each other? No. VHF and UHF are two totally different bands. You cannot use a UHF PA on a VHF repeater and vice-versa. The third one you listed is a Mobile PA - not something you'll want. You want a UHF Station PA like the second one you listed - but it isn't the exact one either. The one you want requires 200 mW of drive - not 20 watts - but, the correct one looks very similar to the one in your number two listing. I don't presently see a good candidate on eBay - but they show up all the time. Duplexer - used WACOM Products WP-678 (or similar), also available from eBay. I couldn't find any on eBay. Any guesses what I'd be paying for something like this? $250 plus shipping. Controller - I recommend a NHRC model that plugs into the Systems board, or, one of the Pion Simon models that plug into the card cage. http://www.nhrc.net/ge-stuff.php http://www.pionsimon.com/products.htm It looks like I can use the NHRC-4/M2 to make it a linked repeater. If I go with the Ham repeater, I'll most likely do that. That would require, if I understand correctly, another radio connected in, so that will have to be done later with future funds. :) Correct. If I decide to make it a GMRS repeater, I won't have to worry about that and will go with the PSE508-2, as its a little less expensive. Also a good choice. Kevin -- --- Michael H. Cox michaelh...@gmail.com
RE: [Repeater-Builder] Mastr II mods and parts
Any reasons? First, it could be used as a duplexer, however you don't get all the benefit you would get from a BpBr duplexer. The one in question is a notch only duplexer, the cavities are designed to notch the two frequencies in use. While it can work, you generally cannot get the required isolation for a fairly sensitive repeater with much of a power output. A more typical duplexer would have band pass cavities, or better yet, band pass band reject cavities. There is a wealth of information on the web regarding the theory and design of duplexers. In short, with a BpBr duplexer, you get two cavities that ONLY pass the receive frequency, and they also notch the transmit frequency. On the transmit side, you get the same double action. This yields more isolation and protects the front end of the receiver a bit from adjacent channel signals by only 'passing' the correct signal. With the notch only duplexer, there is no front end receive protection provided, simply a notch where the transmitter is. If there are other nearby signals they could very well interfere with the receiver. Do the right thing and get a Band Pass Band Reject duplexer, you'll be much happier. 73 Daron N7HQR
Re: [Repeater-Builder] Mastr II mods and parts
Excellent. Thanks for the info. This is going to be my first repeater and so I'm still learning. Thx. Thanks, Michael H. Cox michaelh...@gmail.com -Original Message- From: Daron Wilson daronwil...@yahoo.com Date: Sun, 3 Jan 2010 22:22:05 To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Mastr II mods and parts Any reasons? First, it could be used as a duplexer, however you don't get all the benefit you would get from a BpBr duplexer. The one in question is a notch only duplexer, the cavities are designed to notch the two frequencies in use. While it can work, you generally cannot get the required isolation for a fairly sensitive repeater with much of a power output. A more typical duplexer would have band pass cavities, or better yet, band pass band reject cavities. There is a wealth of information on the web regarding the theory and design of duplexers. In short, with a BpBr duplexer, you get two cavities that ONLY pass the receive frequency, and they also notch the transmit frequency. On the transmit side, you get the same double action. This yields more isolation and protects the front end of the receiver a bit from adjacent channel signals by only 'passing' the correct signal. With the notch only duplexer, there is no front end receive protection provided, simply a notch where the transmitter is. If there are other nearby signals they could very well interfere with the receiver. Do the right thing and get a Band Pass Band Reject duplexer, you'll be much happier. 73 Daron N7HQR
Re: [Repeater-Builder] Cold temps and repeaters
You might want to inspect your connectors first to see if you have any moisture going into the connectors good Amp connectors help out with extremes. Used to have a repeater in NYC. When it snowed or got wet, it squealed and grunted with 9914. Swapped out the old cabe to the good stuff Heiiax and only the connectors gave up problems. On 2010-01-03, George Henry ka3...@att.net wrote: I remember the 146.79 repeater in Henrietta (Rochester) NY back in the mid/late 70's It was housed in an old 'fridge in a shed in the middle of a farm field, at the base of the tower. IIRC, it had a fan to cool it in the summer, and a 25-watt light buld to keep it warm in the winter. KISS at it's best. George, KA3HSW / WQGJ413 - Original Message - From: Chuck Kelsey wb2...@roadrunner.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 03, 2010 2:58 PM Subject: Re: [Repeater-Builder] Cold temps and repeaters I've seen it happen. Changes in temperature can affect the stability of a transmitter causing it to spur. Intermod sources can come and go with weather changes as well. It's 12 chilly degrees here in western New York and the snow has been heavy all day. 45 would be a heat wave ;-) Chuck WB2EDV
Re: [Repeater-Builder] Mastr II mods and parts
mobile duplexers generally have poor performance, not enough for a decent repeater. The model you suggested is one of the worst. -- Original Message -- Received: Sun, 03 Jan 2010 10:04:33 PM PST From: Michael H. Cox michaelh...@gmail.com To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts Any reasons? Thanks, Michael H. Cox michaelh...@gmail.com -Original Message- From: JOHN MACKEY jmac...@usa.net Date: Sun, 03 Jan 2010 21:55:33 To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts I would not recommend that duplexer for a repeater. -- Original Message -- Received: Sun, 03 Jan 2010 08:47:16 PM PST From: Michael Cox michaelh...@gmail.com To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts Will this Duplexer work with the Mastr II repeater? http://cgi.ebay.com/UHF-50W-6-CAVITY-DUPLEXER-FOR-REPEATER-FREE-TUNING_W0QQitemZ350300447727QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item518f88a3ef On Sun, Jan 3, 2010 at 9:32 AM, WA3GIN wa3...@comcast.net wrote: For fun we operated a 400 watt erp repeater with two antennas and no duplexer. We were able to achieve about 100db attenuation by using the roof equipment penthouse. The transmit antenna was mounted on the top of the penthouse and the receive antenna was installed diagonally from the transmit antenna on the roof below the penthouse. Each antenna was physically separated by the penthouse structure. Transmit performance was good and receiver performance was good about 270 degrees minus the abstructed zone. No feedback or other issues. Eventually, we installed TXRX 6 can duplexer and utilized the penthouse antenna. Receive coverage regained 360 degree coverage. So, it is doable if you have the right antenna site. Best, dave wa3gin - Original Message - *From:* Kevin Custer kug...@kuggie.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Sunday, January 03, 2010 11:12 AM *Subject:* Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case. The determining factor usually ends up being the length and size of feed-line necessary to get from the repeater to the antenna. On UHF, unless the feed-line length is really short, you'll want to use some type of hard-line cable. The cost of this cable, depending on type and length, can be costly. It may be less costly to use one antenna and a duplexer then to install two antennas and have two runs of feed-line. In addition, you'll usually end up with a better balanced system using one antenna because using two can cause a disparity if both antennas don't have the exact same pattern - which could be difficult to achieve depending on the tower space available. In installations where you have to pay rent on tower space - it's usually by far cheaper to purchase a duplexer. RE: Power Amplifier Are these what I'm looking for? Generically - Yes. It looks like there is a UHF and a VHF version of the PA. Is that correct? Yes. Are they not compatible with each other? No. VHF and UHF are two totally different bands. You cannot use a UHF PA on a VHF repeater and vice-versa. The third one you listed is a Mobile PA - not something you'll want. You want a UHF Station PA like the second one you listed - but it isn't the exact one either. The one you want requires 200 mW of drive - not 20 watts - but, the correct one looks very similar to the one in your number two listing. I don't presently see a good candidate on eBay - but they show up all the time. Duplexer - used WACOM Products WP-678 (or similar), also available from eBay. I couldn't find any on eBay. Any guesses what I'd be paying for something like this? $250 plus shipping. Controller - I recommend a NHRC model that plugs into the Systems board, or, one of the Pion Simon models that plug into the card cage. http://www.nhrc.net/ge-stuff.php http://www.pionsimon.com/products.htm It looks like I can use the NHRC-4/M2 to make it a linked repeater. If I go with the Ham repeater, I'll most likely do that. That would require, if I understand correctly, another radio connected in, so that will have to be done later with future
Re: [Repeater-Builder] Mastr II mods and parts
Ok. Thx for info. I appreciate it. Thanks, Michael H. Cox michaelh...@gmail.com -Original Message- From: JOHN MACKEY jmac...@usa.net Date: Sun, 03 Jan 2010 22:43:41 To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts mobile duplexers generally have poor performance, not enough for a decent repeater. The model you suggested is one of the worst. -- Original Message -- Received: Sun, 03 Jan 2010 10:04:33 PM PST From: Michael H. Cox michaelh...@gmail.com To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts Any reasons? Thanks, Michael H. Cox michaelh...@gmail.com -Original Message- From: JOHN MACKEY jmac...@usa.net Date: Sun, 03 Jan 2010 21:55:33 To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts I would not recommend that duplexer for a repeater. -- Original Message -- Received: Sun, 03 Jan 2010 08:47:16 PM PST From: Michael Cox michaelh...@gmail.com To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mastr II mods and parts Will this Duplexer work with the Mastr II repeater? http://cgi.ebay.com/UHF-50W-6-CAVITY-DUPLEXER-FOR-REPEATER-FREE-TUNING_W0QQitemZ350300447727QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item518f88a3ef On Sun, Jan 3, 2010 at 9:32 AM, WA3GIN wa3...@comcast.net wrote: For fun we operated a 400 watt erp repeater with two antennas and no duplexer. We were able to achieve about 100db attenuation by using the roof equipment penthouse. The transmit antenna was mounted on the top of the penthouse and the receive antenna was installed diagonally from the transmit antenna on the roof below the penthouse. Each antenna was physically separated by the penthouse structure. Transmit performance was good and receiver performance was good about 270 degrees minus the abstructed zone. No feedback or other issues. Eventually, we installed TXRX 6 can duplexer and utilized the penthouse antenna. Receive coverage regained 360 degree coverage. So, it is doable if you have the right antenna site. Best, dave wa3gin - Original Message - *From:* Kevin Custer kug...@kuggie.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Sunday, January 03, 2010 11:12 AM *Subject:* Re: [Repeater-Builder] Mastr II mods and parts Michael Cox wrote: Thank you for your help. I appreciate it! I've put a couple of questions inline below. Well - you'll need a duplexer no mater the price... grin I was under the impression that if I had two antennas, I could get by without a duplexer. Thanks for the heads up. While two antennas will work, and you'd initially think there is a cost savings using two antennas, that isn't always the case. The determining factor usually ends up being the length and size of feed-line necessary to get from the repeater to the antenna. On UHF, unless the feed-line length is really short, you'll want to use some type of hard-line cable. The cost of this cable, depending on type and length, can be costly. It may be less costly to use one antenna and a duplexer then to install two antennas and have two runs of feed-line. In addition, you'll usually end up with a better balanced system using one antenna because using two can cause a disparity if both antennas don't have the exact same pattern - which could be difficult to achieve depending on the tower space available. In installations where you have to pay rent on tower space - it's usually by far cheaper to purchase a duplexer. RE: Power Amplifier Are these what I'm looking for? Generically - Yes. It looks like there is a UHF and a VHF version of the PA. Is that correct? Yes. Are they not compatible with each other? No. VHF and UHF are two totally different bands. You cannot use a UHF PA on a VHF repeater and vice-versa. The third one you listed is a Mobile PA - not something you'll want. You want a UHF Station PA like the second one you listed - but it isn't the exact one either. The one you want requires 200 mW of drive - not 20 watts - but, the correct one looks very similar to the one in your number two listing. I don't presently see a good candidate on eBay - but they show up all the time. Duplexer - used WACOM Products WP-678 (or similar), also available from eBay. I couldn't find any on eBay. Any guesses what I'd be paying for something like this? $250 plus shipping. Controller - I recommend a NHRC model that plugs into the Systems board, or, one of the Pion Simon models that plug into the card cage. http://www.nhrc.net/ge-stuff.php http://www.pionsimon.com/products.htm
