I have a C85GFB5203AT (896 Conv Rptr) which is not passing audio. The Station Control Board is TLN 3204A35. Everything is working correctly, hang time, COR, CW ID etc... however no receive audio passing to the transmitter. It keys up but doesn't pass audio. Looking at the Station control board, U831 is present and all connected (No, cut or broken legs), however there is no U823 IC. I do know have the schematic for this board so troubleshooting this is hard.
I don't think its something missed in the programming since I programmed the same codeplug into a different Station Control Board and it worked.
Anybody have schematics for this board or any suggestions? All of the jumpers are in the normal default position. Could it be something miss programmed
Thanks in advance,
Mike
MSF5000 Not passing Audio
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Re: MSF5000 Not passing Audio
U823 is the same IC type as U831, an electronic attenuator. The SSCB uses at least half a dozen of them; the TTRC has a few as well. I suspect someone fixed the cut lead on U831 by removing and using U823.
U823 adjusts the Flutter-Fighter level and is controlled as EEPot #1. The Flutter-Fighter is in series with the receiver audio to the rest of the station. Without this pot, you might not get any receive audio.
There are a few work-arounds, but to fix it and get the station back to proper - as designed - operation requires replacing that missing IC.
Bob M.
U823 adjusts the Flutter-Fighter level and is controlled as EEPot #1. The Flutter-Fighter is in series with the receiver audio to the rest of the station. Without this pot, you might not get any receive audio.
There are a few work-arounds, but to fix it and get the station back to proper - as designed - operation requires replacing that missing IC.
Bob M.
Re: MSF5000 Not passing Audio
Thanks I will try that and get back to you. Also noticed that U805 (looks like U805) has a socket for an IC but no IC. Also U823 (the spot for it) looks clean like it was never installed at all.. but I have an extra IC so I will throw that in and see what happens.
Re: MSF5000 Not passing Audio
U808 is an 8-pin socket for an EEPROM to expand the code plug space. It should be the only unoccupied spot/socket on the SSCB.
U823 as noted in my previous post should have been there from day-one, so someone removed it to replace U831. It is very possible to cleanly remove an IC for re-use and make it look like it was never there.
Bob M.
U823 as noted in my previous post should have been there from day-one, so someone removed it to replace U831. It is very possible to cleanly remove an IC for re-use and make it look like it was never there.
Bob M.
Re: MSF5000 Not passing Audio
The station control board that you have, TLN3204, is intended for use in 800 stations, not 896, thus the reason that U823 was not installed.
There are numerous other component differences between frequency band versions of the SSCB - you should get a manual and resolve the applicable issues - or get the correct SSCB for your application.
There are numerous other component differences between frequency band versions of the SSCB - you should get a manual and resolve the applicable issues - or get the correct SSCB for your application.
Re: MSF5000 Not passing Audio
Well I installed the IC in u823 and still no passing audio.. I have manual but not for the SCCB. Any other suggestions. I have been watching Ebay but I havent seen any other SCCB come up.