[Repeater-Builder] Re: MTR2000 UHF Service manual
Just out of curiosity are you performing these tests with a 1000 cycle tone and if so, have you tried it with no modulation? It almost sounds like it is going out of the bandpass of the receiver when you increase the signal level. What happens when you vary the frequency a few KC higher or lower in frequency than your center frequency. I assume you have already tried resetting the radios settings back to factory default settings in the programming software. Joe --- In Repeater-Builder@yahoogroups.com, Camilo So [EMAIL PROTECTED] wrote: Need help to order a MTR2000 service manual that have the schematic diagram of the receiver unit, Got this unit from Ebay, Hook up the unit on my bench with a dummy load on the TX out, and apply signal on the RX input with a IFR1200, The squelch open at 0.12 micro-volt at 0.15 uv its 12 DB Sinad, when signal was increased to about 1.0 micro-volts or higher the receiver drop out, as if the agc is overloaded that cut out completely and also drop the TX, Have anyone ever experience this problem before, This is the first time I have seen this kind of problem , and its hard to fix it w/o a diagram. any help is highly appreciated. de w4cso Camilo
Re: [Repeater-Builder] MTR2000 UHF Service manual
For the benefit of everyone on the list let me advise all of you concerning the new world of Motorola service; at least when compared to the old days when the MSF5000 was considered the top of the line and the days of antiquity when the Micor was king. I will not even try to find adjectives to describe the days of the Motrac as the king of the hill as most Motorolans today have no idea what a Motrac was. ***Disclaimer*** What follows is personal opinion and in no way reflects the views of the list owners or others on the list. It is also not a timeline. When Motorola created the MSF5000 they crossed over from the conventional crystal based designs of many years to a new world of microprocessor based design. The letters MSF stood for Maximum Station Flexability and the MSF was a very capable station. By using software or the R1800 programmer the parameters could be changed easily in the field, repeatedly. It covered wide swaths of RF spectrum in a single radio. Along with the other microprocessor based radios that Motorola was developing it completely changed the direction that most radio shops were going. The new world of radios created a servicing nightmare. The guy on the bench who had been dealing with crystal based designs and leaded componets all his life now had to decide to either update his skills or maybe look elsewhere. A lot of turnover started to take place in the service environment. And then there was that part about being on a mountaintop with a non functioning radio; how did you drag all the items needed to troubleshoot and repair a PLL circuit based radio with you? Or did you drag the station back to the shop? Motorola made a decision that the generation of station equipment that followed the MSF5000 would be based on the concept of Field Replacable Units. Basically break the radio down into building blocks that can easily be swapped out wherever theradio is located with a minimum amount of effort and equipment. Thus the Quantar radio was designed to be a series of modules in a backplane. Initially no service information was released beyond simple, basic in/out diagrams. A similar philosophy holds true with the MTR2000 radio and will, I am sure, continue into the future. One reason is the complexity of the circuitry and the extensive use of leadless componets and new generation chips which combine a multitude of functions in a single device. Another is the need for specialized test and rework equipment in order to even attempt to troubleshoot or repair the circuit boards. As Eric pointed out, you can procure a Depot level manual from Motorola which will have all the required information and schematics. If you are equipped to deal with high density surface mount rework, then go for it. Otherwise there is the depot. Good Luck Milt N3LTQ - Original Message - From: Camilo So To: Repeater-Builder@yahoogroups.com Sent: Monday, October 20, 2008 9:15 PM Subject: Re: [Repeater-Builder] MTR2000 UHF Service manual Oh I forget to mention that I did order a service manual from Motorola 6681096E25 its don't have any circuit diagram on it, What is the correct manual number to order that have a circuit diagram. - Original Message - From: Camilo So To: Repeater-Builder@yahoogroups.com Sent: Monday, October 20, 2008 9:08 PM Subject: [Repeater-Builder] MTR2000 UHF Service manual Need help to order a MTR2000 service manual that have the schematic diagram of the receiver unit, Got this unit from Ebay, Hook up the unit on my bench with a dummy load on the TX out, and apply signal on the RX input with a IFR1200, The squelch open at 0.12 micro-volt at 0.15 uv its 12 DB Sinad, when signal was increased to about 1.0 micro-volts or higher the receiver drop out, as if the agc is overloaded that cut out completely and also drop the TX, Have anyone ever experience this problem before, This is the first time I have seen this kind of problem , and its hard to fix it w/o a diagram. any help is highly appreciated. de w4cso Camilo
[Repeater-Builder] Re: Shutting Down Battery Back up
Don, Low battery voltage shut-down can be done quite simply using three or four parts: a normally open contact relay, a resistor, and a cap. The battery goes to one side of the N. O. contact and the load (repeater?), power supply, and relay coil to the other N. O. contact. The other side of the coil goes to ground via a resistor. The resistor value is determined empirically and should be selected so that the relay will drop out at about ten volts or whatever you decide is the minimum useful voltage. Use a variable DC supply to determine the proper resistance value. You should be able to find a 12 volt relay that needs less than 100 ma. through the coil. An appropriate resistance might be 22 or 27 ohms for this relay. A 1000 MFD cap should be in parallel with the resistor so that when power is restored from the power supply, full voltage is applied to the relay coil for a time to energize it. The resistor also lowers the power used by the relay to a degree. The ubiquitous chatter diode across the relay coil is a good idea as well. I have used this method for several applications at work and it is virtually fool proof. Good luck, Al, K9SI Now the question and I have not seen this talked about I would assume all I would need is a Normally closed Relay and as the Voltage dropped below a Certain Level it would open and just break the connection to the Battery back up , Is this the way to do it Thanks Don KA9QJG
Re: [Repeater-Builder] Re: MTR2000 UHF Service manual
Hi Joe, Yes I did it with a 1000 cycle tone with and with out 1000 cycle but with PL, You are correct I did try to vary the freq, and to my surprise even apply TX freq to RX freq that was 5 MHZ difference it still have the same sensitivity, One thing I did not do is resetting the unit, I am new to this unit, never work on it before, question how do you reset the unit to factory default, is there a reset button or use of software. As you and every one know if you got something off Ebay, That some one already playing around with the unit, it is also possible programming problem, Is there a way to contact you? on phone or Echolink, Thank you for the reply. 73 W4CSO Camilo - Original Message - From: Joe Burkleo To: Repeater-Builder@yahoogroups.com Sent: Tuesday, October 21, 2008 2:13 AM Subject: [Repeater-Builder] Re: MTR2000 UHF Service manual Just out of curiosity are you performing these tests with a 1000 cycle tone and if so, have you tried it with no modulation? It almost sounds like it is going out of the bandpass of the receiver when you increase the signal level. What happens when you vary the frequency a few KC higher or lower in frequency than your center frequency. I assume you have already tried resetting the radios settings back to factory default settings in the programming software. Joe --- In Repeater-Builder@yahoogroups.com, Camilo So [EMAIL PROTECTED] wrote: Need help to order a MTR2000 service manual that have the schematic diagram of the receiver unit, Got this unit from Ebay, Hook up the unit on my bench with a dummy load on the TX out, and apply signal on the RX input with a IFR1200, The squelch open at 0.12 micro-volt at 0.15 uv its 12 DB Sinad, when signal was increased to about 1.0 micro-volts or higher the receiver drop out, as if the agc is overloaded that cut out completely and also drop the TX, Have anyone ever experience this problem before, This is the first time I have seen this kind of problem , and its hard to fix it w/o a diagram. any help is highly appreciated. de w4cso Camilo
Re: [Repeater-Builder] MTR2000 UHF Service manual
Hi Milt its nice for your advice,Yes I have work on surface mount way back maybe 17 years ago at Motorola depot in plantation Florida, and MTR2000 is totally new to me and I like to learn something about this unit, I like to remain active so my old brain won't get frosted, and its boring when you retired doing nothing, Just got this unit off Ebay, it comes with power cord, two fan blower on the PA and power supply side, got the programming software RVN4148M MTR2000 Station RSS R03.02.06 Win, and also ordered the programming cable, now I am a novice trying to learn from you guys like Eric, I just ordered the Depot manual from Motorola the price was up $217.00 and I just buy a 11 X 17 Scanner, in case Eric wanted a copy of the manual. and thanks to all that reply. 73 W4CSO Camilo - Original Message - From: Milt To: Repeater-Builder@yahoogroups.com Sent: Tuesday, October 21, 2008 8:00 AM Subject: Re: [Repeater-Builder] MTR2000 UHF Service manual For the benefit of everyone on the list let me advise all of you concerning the new world of Motorola service; at least when compared to the old days when the MSF5000 was considered the top of the line and the days of antiquity when the Micor was king. I will not even try to find adjectives to describe the days of the Motrac as the king of the hill as most Motorolans today have no idea what a Motrac was. ***Disclaimer*** What follows is personal opinion and in no way reflects the views of the list owners or others on the list. It is also not a timeline. When Motorola created the MSF5000 they crossed over from the conventional crystal based designs of many years to a new world of microprocessor based design. The letters MSF stood for Maximum Station Flexability and the MSF was a very capable station. By using software or the R1800 programmer the parameters could be changed easily in the field, repeatedly. It covered wide swaths of RF spectrum in a single radio. Along with the other microprocessor based radios that Motorola was developing it completely changed the direction that most radio shops were going. The new world of radios created a servicing nightmare. The guy on the bench who had been dealing with crystal based designs and leaded componets all his life now had to decide to either update his skills or maybe look elsewhere. A lot of turnover started to take place in the service environment. And then there was that part about being on a mountaintop with a non functioning radio; how did you drag all the items needed to troubleshoot and repair a PLL circuit based radio with you? Or did you drag the station back to the shop? Motorola made a decision that the generation of station equipment that followed the MSF5000 would be based on the concept of Field Replacable Units. Basically break the radio down into building blocks that can easily be swapped out wherever theradio is located with a minimum amount of effort and equipment. Thus the Quantar radio was designed to be a series of modules in a backplane. Initially no service information was released beyond simple, basic in/out diagrams. A similar philosophy holds true with the MTR2000 radio and will, I am sure, continue into the future. One reason is the complexity of the circuitry and the extensive use of leadless componets and new generation chips which combine a multitude of functions in a single device. Another is the need for specialized test and rework equipment in order to even attempt to troubleshoot or repair the circuit boards. As Eric pointed out, you can procure a Depot level manual from Motorola which will have all the required information and schematics. If you are equipped to deal with high density surface mount rework, then go for it. Otherwise there is the depot. Good Luck Milt N3LTQ - Original Message - From: Camilo So To: Repeater-Builder@yahoogroups.com Sent: Monday, October 20, 2008 9:15 PM Subject: Re: [Repeater-Builder] MTR2000 UHF Service manual Oh I forget to mention that I did order a service manual from Motorola 6681096E25 its don't have any circuit diagram on it, What is the correct manual number to order that have a circuit diagram. - Original Message - From: Camilo So To: Repeater-Builder@yahoogroups.com Sent: Monday, October 20, 2008 9:08 PM Subject: [Repeater-Builder] MTR2000 UHF Service manual Need help to order a MTR2000 service manual that have the schematic diagram of the receiver unit, Got this unit from Ebay, Hook up the unit on my bench with a dummy load on the TX out, and apply signal on the RX input with a IFR1200, The squelch open at 0.12 micro-volt at 0.15 uv its 12 DB Sinad, when signal was increased to about 1.0 micro-volts or higher the receiver drop out, as if the agc is overloaded that cut out completely and also drop the TX, Have
[Repeater-Builder] Re: Ge mastr 2 link question
Mike, Did you just build up these repeaters? If so, you need to remember to install a load on the audio output of the receiver audio amplifier. This can be placed at the speaker connections. If there is not an 8 Ohm load on the audio output, it will produce a low level oscillation in the audio circuits around 500 hz which some people call Hum. I modify my GE Mstr II mobile receivers by adding a switch in series with R616 on the Audio Squelch board which is a 30 ohm resistor feeding regulated 10 volts to the Audio IC U604. Opening this switch turns off the audio amplifier when no speaker audio is desired. This also helps reduce current draw from the receiver. Just a suggestion, John, K7JL Intermountain Intertie 3d. Re: Ge mastr 2 link question Posted by: Mike DeWaele [EMAIL PROTECTED] firechief762 Date: Sun Oct 19, 2008 5:28 pm ((PDT)) Paul, Eric Thanks for the response. I did some more testing with your suggestions. I tried hooking both radios up to a deep cycle battery. The hum is still there so I think that rules out the astrons! The audio from the main repeater to the link isn't as bad as from the link back to the main repeater. Both have a hum to them however the 2 meter to the 440 you can hear the voice. the other way all you get is the hum. For testing I have it on the bench in the basement. the only common connection is only the audio and tx lines between the two radios. I have also tried it with a common ground as suggested by NHRC in the controller directions. Both have the same results. I want to make sure it works here before it goes back to the hill. At the site it's just my radio equipment and Wifi internet which has not given me any problems with both machines working there prior to bringing them to my house to work on this linking project. Maybe tomorrow I will give NHRC a call and see if they have run into this problem before. Thanks, Mike KA2NDW -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] Behalf Of Paul Plack Sent: Sunday, October 19, 2008 4:59 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Ge mastr 2 link question
Re: [Repeater-Builder] Re: Shutting Down Battery Back up
If you are concerned about your batteries lasting as long as possible when running on backup, I would NOT use a relay. Even at 100ma of current draw, that's a LOT of current in a backup / solar situation. Since the RF PA only draws current when in transmit, (Class 'C') you can hook it directly to the battery all the time when line voltage is not present. This can be done easily with normally closed contacts on a relay that is fed from the AC line. Have a look at the cutout circuitry of this solar charge controller: http://www.solorb.com/elect/solarcirc/spc3/ They use a voltage comparator to do the switching. I would think a circuit could be designed that simply used a 10V zener diode and a transistor to feed the power FET. Probably until you would go through all of that, you could have the comparator circuit built and ready to go. The moral of the story is that a comparator and power FET switch would draw FAR less current than using a relay coil. You could also set the comparator EXACTLY where you want the circuit to turn off. Be sure that the hysteresis resistor is a small enough value so that when the circuit cuts out with the transmitter active, it won't turn back on when the battery voltage recovers. Of course, this could be tailored to taste. Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Rd Boswell, PA 15531 - Original Message - From: Al Wolfe [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, October 21, 2008 9:15 AM Subject: [Repeater-Builder] Re: Shutting Down Battery Back up Don, Low battery voltage shut-down can be done quite simply using three or four parts: a normally open contact relay, a resistor, and a cap. The battery goes to one side of the N. O. contact and the load (repeater?), power supply, and relay coil to the other N. O. contact. The other side of the coil goes to ground via a resistor. The resistor value is determined empirically and should be selected so that the relay will drop out at about ten volts or whatever you decide is the minimum useful voltage. Use a variable DC supply to determine the proper resistance value. You should be able to find a 12 volt relay that needs less than 100 ma. through the coil. An appropriate resistance might be 22 or 27 ohms for this relay. A 1000 MFD cap should be in parallel with the resistor so that when power is restored from the power supply, full voltage is applied to the relay coil for a time to energize it. The resistor also lowers the power used by the relay to a degree. The ubiquitous chatter diode across the relay coil is a good idea as well. I have used this method for several applications at work and it is virtually fool proof. Good luck, Al, K9SI Now the question and I have not seen this talked about I would assume all I would need is a Normally closed Relay and as the Voltage dropped below a Certain Level it would open and just break the connection to the Battery back up , Is this the way to do it Thanks Don KA9QJG Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.173 / Virus Database: 270.8.1/1731 - Release Date: 10/17/2008 7:01 PM
[Repeater-Builder] FS: Midland UHF XTR 40W and 100W + Johnson 100W mobile radios
In my long search for UHF Midland XTR Radios I have amassed a large quantity of Midland radios (And some Johnsons) Here's a list, I have several of each model except the 526 Midland 70-526BXL may already be sold Midland 70-1695B Midland 70-1530B Midland 70-1595B Johnson Challenger Plus 242-7187 I have listed them on a new web site I found with prices www.secondhandradio.com http://www.secondhandradio.com/ This site is free to list and free to sell buyers and sellers work out their own arrangements for payment and shipping / pickup. I have no stake in this site, just though it was a great alternative to Ebay. Here's a direct link to my items http://www.secondhandradio.com/Search.aspx?member=ks4ec http://www.secondhandradio.com/Search.aspx?member=ks4ec You can respond right from the website or directly to ks4echome at comcast dot net Thanks for looking - Rob - KS4EC
[Repeater-Builder] 900 MHZ MSF5000's
I have a number of 900 MHz MSF-5000 repeaters available. These units are complete and were all in operation at the time they were taken out of service. I believe they are all Prom Based and the majority were trunked. Most units are 75 Watt, however I do have a few 150W versions. The first 3 model #'s I read were C65GFB5203AT, however, like I said I do have a few other models. I also have SOME site equipment and racks, however there is too much to list. If you need something in particular, please email me your request and I will see what I have. All equipment is located in the Chicago area and may be picked up or shipped per your request. Pricing varies and I am willing to part out a few systems to those who only need specific items Please send all requests to bbfmrf at Yahoo dot com
[Repeater-Builder] Hustler G7-220
anyone on the list have a breakdown,of what the sections are in length ? I was given one that needs repaired,and cant find anything on the net that helps me out.I do have a picture of one section thats in dire need of being fixed. Ray N3PYJ
Re: [Repeater-Builder] Hustler G7-220
top of antenna to top of first white load... 36 7/8bottom of top white load to top of bottom white load 29 bottom of lower load to top of horizontal radials... 31 9/16 hope this helpsallen... **BUY Indiana Jones and the Kingdom of the Crystal Skull on DVD today! (http://pr.atwola.com/promoclk/10075x1209326865x1200539441/aol?redir=http://www.indianajones.com/site/index.html)
[Repeater-Builder] Low band Maratracs on 10m
I see a lot of discussion about 6m conversions for Maratracs... I'm curious about using the low-split model (RF board HLB4099) on 10m FM. The stated range for these units is 29.7 - 36 MHz roughly. Not a huge stretch down into the 10m repeater band. I have a 10m repeater in the conceptual stages, and I've had good results with Maratracs on high band and 440. I'd really like to use them on this machine too. Any wisdom offered is certainly appreciated. Thanks and 73's de N4BWP Brian
RE: [Repeater-Builder] Hustler G7-220
Ray go here __,_._ http://tinyurl.com/5548tq Download the PDF of the Ant Hope this helps Happy Repeater Building Don KA9QJG, ___
Re: [Repeater-Builder] Low band Maratracs on 10m
Read the MaraTrac articles. Modify the programming software and see how it works. You might have to add some ferrite cores in the RX front end coils to bring the sensitivity up a bit at 28 MHz, if you need to go that low, but as the radio is already spec'd to 29.7 and you probably don't need much lower than 29.6, it will most likely make it without modification. Let the rest of us know how you make out. Bob M. == --- On Tue, 10/21/08, Ethercrash [EMAIL PROTECTED] wrote: From: Ethercrash [EMAIL PROTECTED] Subject: [Repeater-Builder] Low band Maratracs on 10m To: Repeater-Builder@yahoogroups.com Date: Tuesday, October 21, 2008, 6:20 PM I see a lot of discussion about 6m conversions for Maratracs... I'm curious about using the low-split model (RF board HLB4099) on 10m FM. The stated range for these units is 29.7 - 36 MHz roughly. Not a huge stretch down into the 10m repeater band. I have a 10m repeater in the conceptual stages, and I've had good results with Maratracs on high band and 440. I'd really like to use them on this machine too. Any wisdom offered is certainly appreciated. Thanks and 73's de N4BWP Brian
RE: [Repeater-Builder] Low band Maratracs on 10m
Brian, If you haven't already you will have to edit the band limits in your copy of the RSS. The procedure varies depending upon which version of the RSS you're using. You will also have to realign the radio a bit but they do work fine on 10m FM. There's info on both Batlabs and the Maratrac Yahoo group. Gary -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Ethercrash Sent: Tuesday, October 21, 2008 3:21 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Low band Maratracs on 10m I see a lot of discussion about 6m conversions for Maratracs... I'm curious about using the low-split model (RF board HLB4099) on 10m FM. The stated range for these units is 29.7 - 36 MHz roughly. Not a huge stretch down into the 10m repeater band. I have a 10m repeater in the conceptual stages, and I've had good results with Maratracs on high band and 440. I'd really like to use them on this machine too. Any wisdom offered is certainly appreciated. Thanks and 73's de N4BWP Brian Yahoo! Groups Links
RE: [Repeater-Builder] Re: Ge mastr 2 link question
Thanks to all that replied with suggestions for my linking problem. With all the answers you gave I was able to resolve the problem. The first mistake was in one radio I forgot to put a load across the speaker connections as I wasn't using one. ( the other radio I did. must have been one of those late night deals). Once I did that the hum went away but the audio was very disorted from the link to main port. Took the audio off speaker hi and connected it to vol arm. Problem solved and now sounds as it should. Now if it ever stops raining it will be back to the hill to reinstall at the site. Once again it's amazing the wealth of information you can get from the repeater builder group! Thanks agian, Mike KA2NDW
Re: [Repeater-Builder] Re: Ge mastr 2 link question
Mike, It's good to hear the problem is resolved, but unless you need the local monitor speaker on a regular basis, it can signifgicantly reduce current consumption on the receiver to disable the B+ supply to the audio amp, rather than run it into an audio dummy load. A set of instructions I once used for converting a Mastr II UHF mobile for full-duplex repeater operation suggested removing the audio output transformer to avoid this problem and save weight. I thought I might one day want the speaker amp functional again, so instead, I unsoldered and lifted one end of a large resistor (or two, don't remember exactly,) to interrupt power to the stage. It's been a long time since I had that manual in front of me, but it was pretty easy to do. Good luck with the weather! 73, Paul, AE4KR - Original Message - From: Mike DeWaele To: Repeater-Builder@yahoogroups.com Sent: Tuesday, October 21, 2008 8:21 PM Subject: RE: [Repeater-Builder] Re: Ge mastr 2 link question Thanks to all that replied with suggestions for my linking problem. With all the answers you gave I was able to resolve the problem. The first mistake was in one radio I forgot to put a load across the speaker connections as I wasn't using one. ( the other radio I did. must have been one of those late night deals). Once I did that the hum went away but the audio was very disorted from the link to main port. Took the audio off speaker hi and connected it to vol arm. Problem solved and now sounds as it should. Now if it ever stops raining it will be back to the hill to reinstall at the site. Once again it's amazing the wealth of information you can get from the repeater builder group! Thanks agian, Mike KA2NDW
RE: [Repeater-Builder] Re: Ge mastr 2 link question
I'm not so sure you have it right yet.. Now you have audio that is not processed, which will bring another wave of 100 helpers. Don't rush it to the hill. Burn it in - listen to the audio. You may need some de-emphasis now. Then the old .2 cap and 15K argument will start. You are not golden yet. One of my suggestions which I always give: Don't rush it to the hill. We always find time to fix it, but we never have time to do it right the first time. Sit on it for a while. Make it work. Try to break it. I have 17 radios, and have one failure every two years. Key it down - burn it in. Bill - W6CBS _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Mike DeWaele Sent: Tuesday, October 21, 2008 7:22 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: Ge mastr 2 link question Thanks to all that replied with suggestions for my linking problem. With all the answers you gave I was able to resolve the problem. The first mistake was in one radio I forgot to put a load across the speaker connections as I wasn't using one. ( the other radio I did. must have been one of those late night deals). Once I did that the hum went away but the audio was very disorted from the link to main port. Took the audio off speaker hi and connected it to vol arm. Problem solved and now sounds as it should. Now if it ever stops raining it will be back to the hill to reinstall at the site. Once again it's amazing the wealth of information you can get from the repeater builder group! Thanks agian, Mike KA2NDW
