Hi all
I have a C65CLB5203AT MSF5000 and want to tune it up to 902 Ham frequecies. I have got the Code plug Eprom programmed for the frequency I want to use.
I have the orginal Eproms from the station and the VCO's go into Lock (green lights on) also have a reference oscillator running on 5mhz as required.
Now the problem, I can not get the VCO's to lock up. I have adjusted each but can not get any movement on meter 5. It dthe oes show adjustment is being made when orginal eprom is in. It does show movement on meter 3.
This is a 896 trunking repeater. The Eprom is programmed for conventional in cabinet repeat.
Is there something I need to do to get the RX & TX VCO's to lock so I can continue to through the tune up procedure.
Also I did run a test on the output of the VCO with a counter and measured 419mhz and can see it moving up or down when I make an adjustment to the VCO.
Thanks
Mike
MSF5000
Moderator: Queue Moderator
Re: MSF5000
M5 should either be very low (around 4uA) or very high (around 46uA) if the VCO isn't locked. You should at least get something there. If it's low, turn the VCO tuning slug Clockwise. If it's high, turn the VCO tuning slug Counter-Clockwise. It may take several turns, just keep going. Eventually it should lock up and M5 will come into range and you can set it for 38uA.
I had one station where M5 was at 46uA and the RX was not locked. It required about 1/4 turn CCW to bring M5 down to 38uA.
The worst that can happen is you run it so far in or out that the slug or locknut comes off. You can remove the VCO from the RF tray and deal with that if/when it happens, but as long as the VCO is running around 400-450 MHz, and moves when you turn the slug, it should make it the rest of the way. The TX VCO runs at 1/2 the TX frequency, so it should be near 464 MHz. The RX VCO runs at 1/2 the RX frequency minus the 21.4 MHz IF, so if you want to receive 901.4 MHz, the VCO runs at 1/2 of 880, or 440 MHz.
Bob M.
I had one station where M5 was at 46uA and the RX was not locked. It required about 1/4 turn CCW to bring M5 down to 38uA.
The worst that can happen is you run it so far in or out that the slug or locknut comes off. You can remove the VCO from the RF tray and deal with that if/when it happens, but as long as the VCO is running around 400-450 MHz, and moves when you turn the slug, it should make it the rest of the way. The TX VCO runs at 1/2 the TX frequency, so it should be near 464 MHz. The RX VCO runs at 1/2 the RX frequency minus the 21.4 MHz IF, so if you want to receive 901.4 MHz, the VCO runs at 1/2 of 880, or 440 MHz.
Bob M.
Re: MSF5000
Bob
Thanks for the reply. The info on the VCO's helps. I can see the RX VCO change when I plug the output into a counter. I am sure I would see the same on the TX side.
As I stated in the first message the orginal Eproms work okay (the Station works) and it looks like the new Code Plug is working as I don't get any errors on the meter except for the Synthesizer with the new plug in place of course as the VCO's aren't locked.
Is there anything thing that I can check to see whats going on with the new Code plug as I am tunning the VCO's.
The Frequencies I have programmed in the new Eprom are 902.1125 and 927.1125 could there be something wrong there?
Thanks for any help
Mike
Thanks for the reply. The info on the VCO's helps. I can see the RX VCO change when I plug the output into a counter. I am sure I would see the same on the TX side.
As I stated in the first message the orginal Eproms work okay (the Station works) and it looks like the new Code Plug is working as I don't get any errors on the meter except for the Synthesizer with the new plug in place of course as the VCO's aren't locked.
Is there anything thing that I can check to see whats going on with the new Code plug as I am tunning the VCO's.
The Frequencies I have programmed in the new Eprom are 902.1125 and 927.1125 could there be something wrong there?
Thanks for any help
Mike
Re: MSF5000
Your problem is that it depends on what freqs the station was on with the old code plug. If the freqs are different by a lot, you'll have to tune the VCOs. I can't say what "a lot" is; 1 MHz could be enough.
Those freqs should be valid for the station and the VCOs should tune to it without any problem. Remember that originally the station would have wanted to receive 896-902 and transmit 935-941. The receive side doesn't have far to go to reach 902-903, but the transmitter will need to go down quite a lot.
I think, but I'm not sure, that turning the VCO tuning slugs clockwise raises the frequency and turning them counter-clockwise lowers the frequency, but that could be entirely backwards. Rather than worry about that, hook your counter to the VCOs and tune them so they're close to the freqs you need: RX = (902.1125 - 21.4) / 2; TX = 927.4125 / 2, then hook them back up into the station and adjust each one for 38uA on M5.
There's also the possibility that the new EPROM wasn't programmed properly. Again, it depends on how far away the freqs are from the previous code plug.
Bob M.
Those freqs should be valid for the station and the VCOs should tune to it without any problem. Remember that originally the station would have wanted to receive 896-902 and transmit 935-941. The receive side doesn't have far to go to reach 902-903, but the transmitter will need to go down quite a lot.
I think, but I'm not sure, that turning the VCO tuning slugs clockwise raises the frequency and turning them counter-clockwise lowers the frequency, but that could be entirely backwards. Rather than worry about that, hook your counter to the VCOs and tune them so they're close to the freqs you need: RX = (902.1125 - 21.4) / 2; TX = 927.4125 / 2, then hook them back up into the station and adjust each one for 38uA on M5.
There's also the possibility that the new EPROM wasn't programmed properly. Again, it depends on how far away the freqs are from the previous code plug.
Bob M.
Re: MSF5000
Thanks for the replies. Does anyone know when you program in just one frequency for this unit does it need to be selected by some means? I do not have a remote control unit for local use. So I am wondering if the Eprom is correct and I just need to select the channel which I know was channel 1 that the frequency was programmed in, or is it just automaticly selected because there is no remote control unit. This could be the problem that I'm overlooking.
Thanks
Mike
Thanks
Mike
Re: MSF5000
My two bits worth:
I notice that you mention 5 meg as required?
The BNC on the side of the station wants to see 14.4meg @ 0 DBM.
Should you input 5 meg you would not synthesize the correct frequency.
I know that this station will tune up on ham frequencies. I have helped with a couple.
This station was used in a system with a common site reference.
The same HSO module as used in the MSF with multicoupler to feed the reference to all stations.
The UHS module has a 5 meg reference oscillator controlling a 14.4 synthesizer.
The same synthesizer is used in paging stations.
Frequency selection:
The station will be on channel (Mode) 1 unless set to another mode by remote control, DC or Tone.
The local frequency switch is only active when the "ACC DIS" is up, which will not allow repeater or remote operation.
This is intended for testing.
Multi channel ham repeaters use an external controller using PTT connected to the front panel TX switch.
The "ACC DIS" switch has to be up, allowing the frequency to be set with the front panel frequency selector.
I notice that you mention 5 meg as required?
The BNC on the side of the station wants to see 14.4meg @ 0 DBM.
Should you input 5 meg you would not synthesize the correct frequency.
I know that this station will tune up on ham frequencies. I have helped with a couple.
This station was used in a system with a common site reference.
The same HSO module as used in the MSF with multicoupler to feed the reference to all stations.
The UHS module has a 5 meg reference oscillator controlling a 14.4 synthesizer.
The same synthesizer is used in paging stations.
Frequency selection:
The station will be on channel (Mode) 1 unless set to another mode by remote control, DC or Tone.
The local frequency switch is only active when the "ACC DIS" is up, which will not allow repeater or remote operation.
This is intended for testing.
Multi channel ham repeaters use an external controller using PTT connected to the front panel TX switch.
The "ACC DIS" switch has to be up, allowing the frequency to be set with the front panel frequency selector.
Aloha, Bernie
Re: MSF5000
Bernie
I appreate your input to my last post. The input you provided about the channel selection helped.
The part about the 5mhz reference is a bit confusing. The 896 MSF5000 that I have has a reference systhesizer that provides the 14.4mhz reference signal to the MSF5000. This Systhesizer has a selectable reference input that can be 100khz,1mhz,5mhz or 10 mhz. Is this what you meant? I have both items and I have a correct output of 14.4 from the reference oscillator by using the 5mhz input on the side of the station.
Let me know if I missed something
Thanks
Mike
I appreate your input to my last post. The input you provided about the channel selection helped.
The part about the 5mhz reference is a bit confusing. The 896 MSF5000 that I have has a reference systhesizer that provides the 14.4mhz reference signal to the MSF5000. This Systhesizer has a selectable reference input that can be 100khz,1mhz,5mhz or 10 mhz. Is this what you meant? I have both items and I have a correct output of 14.4 from the reference oscillator by using the 5mhz input on the side of the station.
Let me know if I missed something
Thanks
Mike
Re: MSF5000
Mike:
My knowledge is limited to the stations that I worked on here in Hawaii.
Bob e mailed me with the same information.
Assuming that the station works with the original code plug, but not with the new CP the problem must be in the CP.
Here is a possibility:
There are two types of synthesizers used in the 800/900 band stations: Mosaic, and non Mosaic.
This selection is made when the CP is programmed on the R1800.
There was a problem with the original synthesizer. Motorola issued new UNIBOARDS as well as new firmware for the R1800
(MSF V8). If you have access to the R1800 you could try setting the other type of synthesizer, or reading and editing your original CP.
The MSF V8 on the R1800 needs to have the model number of the station entered. -A is the original non Mosaic UNIBOARD
-B is the newer Mosaic board. If the programmer is set with the wrong suffix it will not read the existing code plug correctly.
My knowledge is limited to the stations that I worked on here in Hawaii.
Bob e mailed me with the same information.
Assuming that the station works with the original code plug, but not with the new CP the problem must be in the CP.
Here is a possibility:
There are two types of synthesizers used in the 800/900 band stations: Mosaic, and non Mosaic.
This selection is made when the CP is programmed on the R1800.
There was a problem with the original synthesizer. Motorola issued new UNIBOARDS as well as new firmware for the R1800
(MSF V8). If you have access to the R1800 you could try setting the other type of synthesizer, or reading and editing your original CP.
The MSF V8 on the R1800 needs to have the model number of the station entered. -A is the original non Mosaic UNIBOARD
-B is the newer Mosaic board. If the programmer is set with the wrong suffix it will not read the existing code plug correctly.
Aloha, Bernie
Re: MSF5000
Bernie
Thanks for the info on the programming differences. I am not the one doing the programming. I've passed this info on and we will be redoing the Code Plug Eprom. From what your saying if we just modify the orginal Code plug Eprom with the new Freqluency pair etc we should be okay. Not being familar with the programming and my station is a Trunking station is there anything in the programming that asks for information about conventional vs trunking?
Thanks
Mike
Thanks for the info on the programming differences. I am not the one doing the programming. I've passed this info on and we will be redoing the Code Plug Eprom. From what your saying if we just modify the orginal Code plug Eprom with the new Freqluency pair etc we should be okay. Not being familar with the programming and my station is a Trunking station is there anything in the programming that asks for information about conventional vs trunking?
Thanks
Mike
Re: MSF5000
My two bits worth:
In this case you could read and edit the CP.
The trunking function resides in the trunking board, which should be disconnected.
In setting up the R1800 you have to enter your model number.
You might want to use the model number of the closest thing to your application.
The model version is determined by the UNIBOARD.
Depending whether you have a non-mosaic (A) or a mosaic (B) sets a bit that determines the divide by in the synthesizer.
If you enter the wrong choice the frequency read out will be very wrong when viewing the CP image.
In this case you could read and edit the CP.
The trunking function resides in the trunking board, which should be disconnected.
In setting up the R1800 you have to enter your model number.
You might want to use the model number of the closest thing to your application.
The model version is determined by the UNIBOARD.
Depending whether you have a non-mosaic (A) or a mosaic (B) sets a bit that determines the divide by in the synthesizer.
If you enter the wrong choice the frequency read out will be very wrong when viewing the CP image.
Aloha, Bernie