[Premium-Rx] TELEFUNKEN E1500 RX - DEMODULATOR MODULE DE1500 - INFO REQUESTED

[Pat1McA at aol.com]

Hello All,
 
I have an ex Military (?) Telefunken E1500 HF Receiver in for  repair.
 
After fixing the AO1500 synthesiser there is audio  distortion and a lack of 
any agc when the demodulator mode  is switched to A3J with "LONG AGC" selected.
 
The DE1500 Demodulator in this model E1500 is completely  different to the 
later (?) DE1500 usually found in the E1501/1506 and the  similar later DE1700 
in the E1700.
 
This particular DE1500 has a "hang" type agc with a Plessey SL621  IC in it 
that appears to generate the agc control voltage.
 
This looks like it is controlled by a series of Hex Inverters  from the front 
panel switch and I suspect the switching is faulty.
 
Is there anyone out there with a circuit please for this  particular model 
DE1500 Demod?  
 
Just to confuse things there are a number of factory modifications on the  
board as well. Never give up!
 
Thanks,
 
Pat G3YFK
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