Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
At 12/13/2007 13:01, you wrote: By the way, if you have not noticed it yet, the RUS signal on a GE system is a combination of the COS and CTCSS signals, and works great as the COS input to your controller. It shows a slight delay coming up (while the CTCSS decoder locks up) but turns off Actually, I've found that the RUS line has a slight delay even without using CTCSS. This has the effect of making picket fencing sound much worse because the squelch stays closed for a greater percentage of the time. I use the CAS signal (J912 on the MVP SAS board) add a 3.3 uF cap to pin 13 of U901 to make the MVP squelch work like a Mastr II mobile squelch. Also, be sure to do the squelch mod documented on the RB site. You will be very pleased with the results. If you use a stock SAS board from a station, it will cause a lot of pops and such in the audio as the COS goes up and down when a station is picket fencing. The squelch mod completely eliminates that problem. You may find the caps already installed, but the .82 cap needs to be replaced with the larger value. I've yet to try this mod., but am concerned that increasing C631 (C905 on the MVP) may degrade the fast squelch action, which is already a few milliseconds slower to release on strong signals than the Micor squelch. Has anyone measured the difference in short squelch mode before after this mod? Bob NO6B
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
At 12/13/2007 09:48, you wrote: Randy, I've experienced problems similar to what you describe on several MII and found it to be harmonic noise on the ptt (osc 10v) line. Installing a 10 uh inductor where the line enters the exciter pcb did wonders for mine. You may also want to install a pair of inductors on the 12v lines in the PA (at the feed through caps). The original GE design has this on a number of their PAs. While, once I did have a spur that required me to move the entire mobile radio away from another mobile cased unit, I've never had a desense problem internally between the tx and rx in a mobile. NO6B may want to revisit his problem MII and look at the ptt line. He may be pleasantly surprised. I'll have to try that next time I have the radio in front of me; thanks Steve.The spurs I'm seeing are not being manufactured in the PA, as they're present on the exciter output. I tried capacitive bypassing on the OSC 10V line, but perhaps that wasn't enough. Bob NO6B
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
At 12/14/2007 07:50, you wrote: At 12/13/2007 13:01, you wrote: By the way, if you have not noticed it yet, the RUS signal on a GE system is a combination of the COS and CTCSS signals, and works great as the COS input to your controller. It shows a slight delay coming up (while the CTCSS decoder locks up) but turns off Actually, I've found that the RUS line has a slight delay even without using CTCSS. This has the effect of making picket fencing sound much worse because the squelch stays closed for a greater percentage of the time. I use the CAS signal (J912 on the MVP SAS board) add a 3.3 uF cap to pin 13 of U901 to make the MVP squelch work like a Mastr II mobile squelch. Oops, that should have been 4.7 uF on pin 13 (had Micor squelch on my mind) of course it goes to ground. Bob NO6B
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
You're welcome. The spurs I was referring to weren't from the PA either. They were generated in the exciter. The PA just appeared to amplify them. Moving the exciter output from the PA and into the service monitor, showed the spurs. After installing the inductor where the ptt line enters the exciter pcb, caused the spur to be lost in the noise floor. Then after moving the exciter output back to the PA, the spurs appeared clearly above the noise floor. Installing the inductors on the PA reduced them back into the noise floor. That is probably why GE put the inductors on their problematic PA version's voltage Supply. Again, the spurs were actually being generated in the exciter, by the icom's osc, from noise on the ptt line feeding it. The sources of that noise could be many -- even external to the MII. -Steve - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, December 14, 2007 7:57 AM Subject: Re: [Repeater-Builder] Re: MastrII Mobil repeater spur At 12/13/2007 09:48, you wrote: Randy, I've experienced problems similar to what you describe on several MII and found it to be harmonic noise on the ptt (osc 10v) line. Installing a 10 uh inductor where the line enters the exciter pcb did wonders for mine. You may also want to install a pair of inductors on the 12v lines in the PA (at the feed through caps). The original GE design has this on a number of their PAs. While, once I did have a spur that required me to move the entire mobile radio away from another mobile cased unit, I've never had a desense problem internally between the tx and rx in a mobile. NO6B may want to revisit his problem MII and look at the ptt line. He may be pleasantly surprised. I'll have to try that next time I have the radio in front of me; thanks Steve.The spurs I'm seeing are not being manufactured in the PA, as they're present on the exciter output. I tried capacitive bypassing on the OSC 10V line, but perhaps that wasn't enough. Bob NO6B Yahoo! Groups Links
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
Bob, I have four repeaters in service using a Zetron 38A controller, and had the following experience. When I enabled the courtesy tone at the end of a transmission a station that was on the edge and 'picket fencing' would be unreadable for all the beeps the controller would insert. It seems the Zetron would insert the beep for any drop in the CAS line. I had to disable the courtesy tone on all the repeaters. When I did the squelch board mod, this problem went away. I was able to put the courtesy tone back in on all the repeaters as I modified the SAS boards with the new capacitor values and no extraneous beeps occured with a 'picket fencing' signal. It seems that the quick cycling of the CAS line was triggering off the beeps even though the CAS came right back up, but the Zetron was committed to outputing the beep, and destroying the intelligability of the station transmitting. I think the problem you have experienced when using RUS in place of CAS would go away if you had also implemented the SAS mod recommended on the RB site. Those problems sure went away for me as I first had the problem and then saw it go completely away when the squelch mod was performed. It was so bad that one of the repeaters was operated open squelch to keep the problem from occuring. (That turned out to be a disaster when the power was removed from the Zetron and brought back up with the squelch open (the repeater was dead)- the Zetron will not initialize properly with the squelch open) 73 - Jim W5ZIT --- [EMAIL PROTECTED] wrote: At 12/13/2007 13:01, you wrote: By the way, if you have not noticed it yet, the RUS signal on a GE system is a combination of the COS and CTCSS signals, and works great as the COS input to your controller. It shows a slight delay coming up (while the CTCSS decoder locks up) but turns off Actually, I've found that the RUS line has a slight delay even without using CTCSS. This has the effect of making picket fencing sound much worse because the squelch stays closed for a greater percentage of the time. I use the CAS signal (J912 on the MVP SAS board) add a 3.3 uF cap to pin 13 of U901 to make the MVP squelch work like a Mastr II mobile squelch. Also, be sure to do the squelch mod documented on the RB site. You will be very pleased with the results. If you use a stock SAS board from a station, it will cause a lot of pops and such in the audio as the COS goes up and down when a station is picket fencing. The squelch mod completely eliminates that problem. You may find the caps already installed, but the .82 cap needs to be replaced with the larger value. I've yet to try this mod., but am concerned that increasing C631 (C905 on the MVP) may degrade the fast squelch action, which is already a few milliseconds slower to release on strong signals than the Micor squelch. Has anyone measured the difference in short squelch mode before after this mod? Bob NO6B Looking for last minute shopping deals? Find them fast with Yahoo! Search. http://tools.search.yahoo.com/newsearch/category.php?category=shopping
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
At 12/14/2007 17:56, you wrote: Bob, I have four repeaters in service using a Zetron 38A controller, and had the following experience. When I enabled the courtesy tone at the end of a transmission a station that was on the edge and 'picket fencing' would be unreadable for all the beeps the controller would insert. It seems the Zetron would insert the beep for any drop in the CAS line. I had to disable the courtesy tone on all the repeaters. I don't/wouldn't use a controller that didn't have any courtesy tone delay. When I did the squelch board mod, this problem went away. I was able to put the courtesy tone back in on all the repeaters as I modified the SAS boards with the new capacitor values and no extraneous beeps occured with a 'picket fencing' signal. It seems that the quick cycling of the CAS line was triggering off the beeps even though the CAS came right back up, but the Zetron was committed to outputing the beep, and destroying the intelligability of the station transmitting. I think the problem you have experienced when using RUS in place of CAS would go away if you had also implemented the SAS mod recommended on the RB site. I don't see how increasing the value of a capacitor would reduce the squelch attack time. OTOH it may increase the fast squelch release time, which would be very undesirable IMO. If I get some time I'll try the mod. measure the length of the FQ squelch tail before after the capacitor change. Bob NO6B
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
Randy, The conversion I did was based on instructions from the guy who sold the radios, out of a shop in Colorado or Wyoming, if I recall...he suggested just running the controller cable through a hole in the front of the rig, and soldering the wires inside the radio. I did that, put a DB25 plug on the cable to mate with the 7K, and it worked out fine. His conversions also called for removing the audio transformer from the receiver, and I was glad I did that one. Less weight, less current draw on receive. That mobile conversion went on the air on 442.250 in Orlando as AE4KR/R in about 1995. i left it with friends when I moved away in 1997. It ate a PA in 2004, but is otherwise still running fine, now known as AE4KO/R. (Yep - Aaron and I got our Extra Class tickets in the same VE session!) 73, Paul, AE4KR - Original Message - From: wb8art To: Repeater-Builder@yahoogroups.com Sent: Thursday, December 13, 2007 4:44 AM Subject: [Repeater-Builder] Re: MastrII Mobil repeater spur Thanks Bob Paul for the response. Yes it is the unit with the compensation line running between all ICOMS. This is kind of where I have been leaning to.. Course the consternation is that its been working for a long time without an issue or at least one on that freq. It may have just moved to a location to be noticed. I will purse it some more and Bob I suspect you maybe ahead of us on this. I have a station I am working on to replace the mobiles so may not worry about this to long. Question while on the topic. How do you guys generally connect the controller to a station? Do you get the Molex connectors and pins or what exactly? If so, you have a easy source on and nos. for the pins and plugs? Thanks Randy --- In Repeater-Builder@yahoogroups.com, Paul Plack [EMAIL PROTECTED] wrote: Randy, I'm trying to recall...is this a rig where one ICOM has the temperature compensation network, and develops a control voltage which is then distributed and shared by all the other ICOMs in the radio? If so, and the problem just showed up one day, perhaps there's some RF bypass cap or other component that's failed within the ICOM itself, allowing RF to travel that DC temperature control line. It's been 10 years since my last MII mobile conversion, so the memories are somewhat dusty, but I'd try another ICOM to see. 73, Paul, AE4KR - Original Message - From: wb8art To: Repeater-Builder@yahoogroups.com Sent: Wednesday, December 12, 2007 6:06 AM Subject: [Repeater-Builder] MastrII Mobil repeater spur One for the wonderfull experts here. I have been working to many nights this week to be able to think straight. Our MastrII converted mobil developed a spur problem last nite. Were on 145.43 and the spur was on 145.11. Very strong and subbing in a standy unit produced the same results. The only components used in both are the ICOMs and the stock tone card (used to encode tone only). The fix was to pull the reciever ICOM (144.83)killing the local rx. Guys what are your thoughts on this and the possible fix. Randy
[Repeater-Builder] Re: MastrII Mobil repeater spur
Thanks Bob Paul for the response. Yes it is the unit with the compensation line running between all ICOMS. This is kind of where I have been leaning to.. Course the consternation is that its been working for a long time without an issue or at least one on that freq. It may have just moved to a location to be noticed. I will purse it some more and Bob I suspect you maybe ahead of us on this. I have a station I am working on to replace the mobiles so may not worry about this to long. Question while on the topic. How do you guys generally connect the controller to a station? Do you get the Molex connectors and pins or what exactly? If so, you have a easy source on and nos. for the pins and plugs? Thanks Randy --- In Repeater-Builder@yahoogroups.com, Paul Plack [EMAIL PROTECTED] wrote: Randy, I'm trying to recall...is this a rig where one ICOM has the temperature compensation network, and develops a control voltage which is then distributed and shared by all the other ICOMs in the radio? If so, and the problem just showed up one day, perhaps there's some RF bypass cap or other component that's failed within the ICOM itself, allowing RF to travel that DC temperature control line. It's been 10 years since my last MII mobile conversion, so the memories are somewhat dusty, but I'd try another ICOM to see. 73, Paul, AE4KR - Original Message - From: wb8art To: Repeater-Builder@yahoogroups.com Sent: Wednesday, December 12, 2007 6:06 AM Subject: [Repeater-Builder] MastrII Mobil repeater spur One for the wonderfull experts here. I have been working to many nights this week to be able to think straight. Our MastrII converted mobil developed a spur problem last nite. Were on 145.43 and the spur was on 145.11. Very strong and subbing in a standy unit produced the same results. The only components used in both are the ICOMs and the stock tone card (used to encode tone only). The fix was to pull the reciever ICOM (144.83)killing the local rx. Guys what are your thoughts on this and the possible fix. Randy
[Repeater-Builder] Re: MastrII Mobil repeater spur
Yes I checked power levels and change in power has no effect on the issue. Yes see where the connections are on a station/repeater. More a question of how of it. With Molex connectors on backplane or what works the best? Randy --- In Repeater-Builder@yahoogroups.com, Jim Brown [EMAIL PROTECTED] wrote: If the spur is causing a particular problem to someone and is caused by some harmonic of the LO chain beating with the transmitter, you could move the beat by changing to the opposite side injection on the receiver. Check the new beat frequencies to make sure you are not just trading one problem for another. Another possible source of a spur is if you have reduced the power output of the final amp below about 60% of full power. Some amps will not tolerate running below rated output without developing spurs. By the way, check the Repeater-Builder web site for suggestions on where to connect your controller to the backplane on the GE Station. 73 - Jim W5ZIT --- wb8art [EMAIL PROTECTED] wrote: Thanks Bob Paul for the response. Yes it is the unit with the compensation line running between all ICOMS. This is kind of where I have been leaning to.. Course the consternation is that its been working for a long time without an issue or at least one on that freq. It may have just moved to a location to be noticed. I will purse it some more and Bob I suspect you maybe ahead of us on this. I have a station I am working on to replace the mobiles so may not worry about this to long. Question while on the topic. How do you guys generally connect the controller to a station? Do you get the Molex connectors and pins or what exactly? If so, you have a easy source on and nos. for the pins and plugs? Thanks Randy --- In Repeater-Builder@yahoogroups.com, Paul Plack pwplack@ wrote: Randy, I'm trying to recall...is this a rig where one ICOM has the temperature compensation network, and develops a control voltage which is then distributed and shared by all the other ICOMs in the radio? If so, and the problem just showed up one day, perhaps there's some RF bypass cap or other component that's failed within the ICOM itself, allowing RF to travel that DC temperature control line. It's been 10 years since my last MII mobile conversion, so the memories are somewhat dusty, but I'd try another ICOM to see. 73, Paul, AE4KR - Original Message - From: wb8art To: Repeater-Builder@yahoogroups.com Sent: Wednesday, December 12, 2007 6:06 AM Subject: [Repeater-Builder] MastrII Mobil repeater spur One for the wonderfull experts here. I have been working to many nights this week to be able to think straight. Our MastrII converted mobil developed a spur problem last nite. Were on 145.43 and the spur was on 145.11. Very strong and subbing in a standy unit produced the same results. The only components used in both are the ICOMs and the stock tone card (used to encode tone only). The fix was to pull the reciever ICOM (144.83)killing the local rx. Guys what are your thoughts on this and the possible fix. Randy __ __ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
If the spur is causing a particular problem to someone and is caused by some harmonic of the LO chain beating with the transmitter, you could move the beat by changing to the opposite side injection on the receiver. Check the new beat frequencies to make sure you are not just trading one problem for another. Another possible source of a spur is if you have reduced the power output of the final amp below about 60% of full power. Some amps will not tolerate running below rated output without developing spurs. By the way, check the Repeater-Builder web site for suggestions on where to connect your controller to the backplane on the GE Station. 73 - Jim W5ZIT --- wb8art [EMAIL PROTECTED] wrote: Thanks Bob Paul for the response. Yes it is the unit with the compensation line running between all ICOMS. This is kind of where I have been leaning to.. Course the consternation is that its been working for a long time without an issue or at least one on that freq. It may have just moved to a location to be noticed. I will purse it some more and Bob I suspect you maybe ahead of us on this. I have a station I am working on to replace the mobiles so may not worry about this to long. Question while on the topic. How do you guys generally connect the controller to a station? Do you get the Molex connectors and pins or what exactly? If so, you have a easy source on and nos. for the pins and plugs? Thanks Randy --- In Repeater-Builder@yahoogroups.com, Paul Plack [EMAIL PROTECTED] wrote: Randy, I'm trying to recall...is this a rig where one ICOM has the temperature compensation network, and develops a control voltage which is then distributed and shared by all the other ICOMs in the radio? If so, and the problem just showed up one day, perhaps there's some RF bypass cap or other component that's failed within the ICOM itself, allowing RF to travel that DC temperature control line. It's been 10 years since my last MII mobile conversion, so the memories are somewhat dusty, but I'd try another ICOM to see. 73, Paul, AE4KR - Original Message - From: wb8art To: Repeater-Builder@yahoogroups.com Sent: Wednesday, December 12, 2007 6:06 AM Subject: [Repeater-Builder] MastrII Mobil repeater spur One for the wonderfull experts here. I have been working to many nights this week to be able to think straight. Our MastrII converted mobil developed a spur problem last nite. Were on 145.43 and the spur was on 145.11. Very strong and subbing in a standy unit produced the same results. The only components used in both are the ICOMs and the stock tone card (used to encode tone only). The fix was to pull the reciever ICOM (144.83)killing the local rx. Guys what are your thoughts on this and the possible fix. Randy Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
Randy, a method I have used a couple of times is to take an old computer card back-panel with a cutout for a 9 or 25 pin connector and bend it so that it picks up a couple of screws on the rear of the card cage top or bottom. (You kept those and did not throw them away did'nt you) I then wired the various points on the card cage back to pins on the connector and interfaced it that way. I have even used a standard 25 pin computer serial cable to connect between one of Ron Wright's RC-1000 controllers and a 25 pin connector I installed this way. Makes a pretty clean installation, although one of the controller manufacturers on here recommended against using computer serial cables as interconnects for controllers - HI. Worked fine for me though - 73 - Jim W5ZIT --- wb8art [EMAIL PROTECTED] wrote: Yes I checked power levels and change in power has no effect on the issue. Yes see where the connections are on a station/repeater. More a question of how of it. With Molex connectors on backplane or what works the best? Randy Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
Randy, I've experienced problems similar to what you describe on several MII and found it to be harmonic noise on the ptt (osc 10v) line. Installing a 10 uh inductor where the line enters the exciter pcb did wonders for mine. You may also want to install a pair of inductors on the 12v lines in the PA (at the feed through caps). The original GE design has this on a number of their PAs. While, once I did have a spur that required me to move the entire mobile radio away from another mobile cased unit, I've never had a desense problem internally between the tx and rx in a mobile. NO6B may want to revisit his problem MII and look at the ptt line. He may be pleasantly surprised. -Steve - Original Message - From: wb8art To: Repeater-Builder@yahoogroups.com Sent: Thursday, December 13, 2007 4:44 AM Subject: [Repeater-Builder] Re: MastrII Mobil repeater spur Thanks Bob Paul for the response. Yes it is the unit with the compensation line running between all ICOMS. This is kind of where I have been leaning to.. Course the consternation is that its been working for a long time without an issue or at least one on that freq. It may have just moved to a location to be noticed. I will purse it some more and Bob I suspect you maybe ahead of us on this. I have a station I am working on to replace the mobiles so may not worry about this to long. Question while on the topic. How do you guys generally connect the controller to a station? Do you get the Molex connectors and pins or what exactly? If so, you have a easy source on and nos. for the pins and plugs? Thanks Randy --- In Repeater-Builder@yahoogroups.com, Paul Plack [EMAIL PROTECTED] wrote: Randy, I'm trying to recall...is this a rig where one ICOM has the temperature compensation network, and develops a control voltage which is then distributed and shared by all the other ICOMs in the radio? If so, and the problem just showed up one day, perhaps there's some RF bypass cap or other component that's failed within the ICOM itself, allowing RF to travel that DC temperature control line. It's been 10 years since my last MII mobile conversion, so the memories are somewhat dusty, but I'd try another ICOM to see. 73, Paul, AE4KR - Original Message - From: wb8art To: Repeater-Builder@yahoogroups.com Sent: Wednesday, December 12, 2007 6:06 AM Subject: [Repeater-Builder] MastrII Mobil repeater spur One for the wonderfull experts here. I have been working to many nights this week to be able to think straight. Our MastrII converted mobil developed a spur problem last nite. Were on 145.43 and the spur was on 145.11. Very strong and subbing in a standy unit produced the same results. The only components used in both are the ICOMs and the stock tone card (used to encode tone only). The fix was to pull the reciever ICOM (144.83)killing the local rx. Guys what are your thoughts on this and the possible fix. Randy Yahoo! Groups Links
[Repeater-Builder] Re: MastrII Mobil repeater spur
Hi Jim, So you just solder wires onto the back plane circuit board? I quess this is my quest to see where most people connect to the repeater. Randy --- In Repeater-Builder@yahoogroups.com, Jim Brown [EMAIL PROTECTED] wrote: Randy, a method I have used a couple of times is to take an old computer card back-panel with a cutout for a 9 or 25 pin connector and bend it so that it picks up a couple of screws on the rear of the card cage top or bottom. (You kept those and did not throw them away did'nt you) I then wired the various points on the card cage back to pins on the connector and interfaced it that way. I have even used a standard 25 pin computer serial cable to connect between one of Ron Wright's RC-1000 controllers and a 25 pin connector I installed this way. Makes a pretty clean installation, although one of the controller manufacturers on here recommended against using computer serial cables as interconnects for controllers - HI. Worked fine for me though - 73 - Jim W5ZIT --- wb8art [EMAIL PROTECTED] wrote: Yes I checked power levels and change in power has no effect on the issue. Yes see where the connections are on a station/repeater. More a question of how of it. With Molex connectors on backplane or what works the best? Randy __ __ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
[Repeater-Builder] Re: MastrII Mobil repeater spur
I will look into that when we get a chance. Thanks for the thought. Randy --- In Repeater-Builder@yahoogroups.com, Steve Smith [EMAIL PROTECTED] wrote: Randy, I've experienced problems similar to what you describe on several MII and found it to be harmonic noise on the ptt (osc 10v) line. Installing a 10 uh inductor where the line enters the exciter pcb did wonders for mine. You may also want to install a pair of inductors on the 12v lines in the PA (at the feed through caps). The original GE design has this on a number of their PAs. While, once I did have a spur that required me to move the entire mobile radio away from another mobile cased unit, I've never had a desense problem internally between the tx and rx in a mobile. NO6B may want to revisit his problem MII and look at the ptt line. He may be pleasantly surprised. -Steve - Original Message - From: wb8art To: Repeater-Builder@yahoogroups.com Sent: Thursday, December 13, 2007 4:44 AM Subject: [Repeater-Builder] Re: MastrII Mobil repeater spur Thanks Bob Paul for the response. Yes it is the unit with the compensation line running between all ICOMS. This is kind of where I have been leaning to.. Course the consternation is that its been working for a long time without an issue or at least one on that freq. It may have just moved to a location to be noticed. I will purse it some more and Bob I suspect you maybe ahead of us on this. I have a station I am working on to replace the mobiles so may not worry about this to long. Question while on the topic. How do you guys generally connect the controller to a station? Do you get the Molex connectors and pins or what exactly? If so, you have a easy source on and nos. for the pins and plugs? Thanks Randy --- In Repeater-Builder@yahoogroups.com, Paul Plack pwplack@ wrote: Randy, I'm trying to recall...is this a rig where one ICOM has the temperature compensation network, and develops a control voltage which is then distributed and shared by all the other ICOMs in the radio? If so, and the problem just showed up one day, perhaps there's some RF bypass cap or other component that's failed within the ICOM itself, allowing RF to travel that DC temperature control line. It's been 10 years since my last MII mobile conversion, so the memories are somewhat dusty, but I'd try another ICOM to see. 73, Paul, AE4KR - Original Message - From: wb8art To: Repeater-Builder@yahoogroups.com Sent: Wednesday, December 12, 2007 6:06 AM Subject: [Repeater-Builder] MastrII Mobil repeater spur One for the wonderfull experts here. I have been working to many nights this week to be able to think straight. Our MastrII converted mobil developed a spur problem last nite. Were on 145.43 and the spur was on 145.11. Very strong and subbing in a standy unit produced the same results. The only components used in both are the ICOMs and the stock tone card (used to encode tone only). The fix was to pull the reciever ICOM (144.83)killing the local rx. Guys what are your thoughts on this and the possible fix. Randy Yahoo! Groups Links
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
Yep - I used the info on the Repeater-Builder site to identify the pick off points where the signals are found, and soldered directly to the backside of the pin that the boards plug into on the other side. You can figure out which points they are by looking at a schematic of the card cage also. But it was all laid out in the note on the RB site. By the way, if you have not noticed it yet, the RUS signal on a GE system is a combination of the COS and CTCSS signals, and works great as the COS input to your controller. It shows a slight delay coming up (while the CTCSS decoder locks up) but turns off instantly when the COS goes down. This allows you to use a stock GE CTCSS board plugged into the receiver system board. Conversely, if your controller can use both COS and CTCSS detects, Hook up the COS direct to the controller and hook the RUS signal up as the tone detect. They both go positive when active. Also, be sure to do the squelch mod documented on the RB site. You will be very pleased with the results. If you use a stock SAS board from a station, it will cause a lot of pops and such in the audio as the COS goes up and down when a station is picket fencing. The squelch mod completely eliminates that problem. You may find the caps already installed, but the .82 cap needs to be replaced with the larger value. I have found several boards from stations that did not have one of the caps installed at all. 73 - Jim W5ZIT --- wb8art [EMAIL PROTECTED] wrote: Hi Jim, So you just solder wires onto the back plane circuit board? I quess this is my quest to see where most people connect to the repeater. Randy Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs
[Repeater-Builder] Re: MastrII Mobil repeater spur
QSL Jim and yes I am aware of RUS CAS and with the dual squelch mod as have been running MastrII mobils for years as repeater and MVP's for remote RX and links. Kind wished the PS unit was set to loop out to a voter and back. Guess we can roll our own. Still to looking for the controller in the station upgrade. Thanks and Merry Xmas and all Randy --- In Repeater-Builder@yahoogroups.com, Jim Brown [EMAIL PROTECTED] wrote: Yep - I used the info on the Repeater-Builder site to identify the pick off points where the signals are found, and soldered directly to the backside of the pin that the boards plug into on the other side. You can figure out which points they are by looking at a schematic of the card cage also. But it was all laid out in the note on the RB site. By the way, if you have not noticed it yet, the RUS signal on a GE system is a combination of the COS and CTCSS signals, and works great as the COS input to your controller. It shows a slight delay coming up (while the CTCSS decoder locks up) but turns off instantly when the COS goes down. This allows you to use a stock GE CTCSS board plugged into the receiver system board. Conversely, if your controller can use both COS and CTCSS detects, Hook up the COS direct to the controller and hook the RUS signal up as the tone detect. They both go positive when active. Also, be sure to do the squelch mod documented on the RB site. You will be very pleased with the results. If you use a stock SAS board from a station, it will cause a lot of pops and such in the audio as the COS goes up and down when a station is picket fencing. The squelch mod completely eliminates that problem. You may find the caps already installed, but the .82 cap needs to be replaced with the larger value. I have found several boards from stations that did not have one of the caps installed at all. 73 - Jim W5ZIT --- wb8art [EMAIL PROTECTED] wrote: Hi Jim, So you just solder wires onto the back plane circuit board? I quess this is my quest to see where most people connect to the repeater. Randy __ __ Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs
Re: [Repeater-Builder] Re: MastrII Mobil repeater spur
Hi Jim, Makes a pretty clean installation, although one of the controller manufacturers on here recommended against using computer serial cables as interconnects for controllers That'd be us. A PC cable consisting of two D-sub connectors and a long, 25-conductor cable enclosed within a single shield has a lot of capacitance between conductors and allows a surprising amount of crosstalk. Years ago we were getting reports that the controllers weren't fully muting DTMF, or there was an echo on the repeat audio caused by the audio delay, things like that. In each case the customer was using a computer cable rather than individually-shielded RX and TX audio lines, and that's what led to the investigation and recommendation. 73, Bob Bob Schmid, WA9FBO, Member S-COM, LLC PO Box 1546 LaPorte CO 80535-1546 970-416-6505 voice 970-419-3222 fax www.scomcontrollers.com **See AOL's top rated recipes (http://food.aol.com/top-rated-recipes?NCID=aoltop000304)
