[Premium-Rx] HRB Systems Tunable Demodulator

[davesc50]

Hi,Long shot this, but I've just acquired an HRB Systems 1390A tunable demodulator.It's working fine except for the rotary encoder.It can be tuned using the serial port but the encoder does nothing.The encoder looks fine, I can see the output entering a PALCE16V8Q-25 which I guess is supposed to be decoding the pulses and producing a tune up / down signal to the micro, but I am getting nothing on any of the other pins.I am looking for any service info / schematics to confirm my theory, and if possible someone who has a working unit that they can read their PAL fuse map for me. That way I can blow a new PAL, I'm pretty happy that will fix it.Even without the PAL info I can always add a micro controller or such like to mimic it once I know what it's supposed to do....Thanks in advance,Dave. S.Sent from my Galaxy