[Premium-Rx] TELEFUNKEN E1500 HELP REQUESTED

[Pat1McA at aol.com]

Greetings all,
 
I have just got a (1974) model (R1500) Telefunken E1500 HF Receiver in  for 
repair that a friend of mine bought from a dealer in Germany last  year.
 
The receiver is totally deaf. It was working perfectly and suddenly just  
lost all received signals.
 
I have the book in German but there are no circuits/schematics at all  and 
only a simple block diagram is available. That, coupled with the fact that  
custom DIN extenders are required, makes fault finding difficult!
 
At first I suspected the AO1500 synthesiser.The First Local Osc  output gives 
42.2-72.2MHz at approx -10dBm .The Second LO gives  42.00MHz at -15dBm into 
50R. Maybe this is correct?
 
It would appear that neither the First or Second Mixers in the HT1500LH RF  
Front End module are working at all. I am beginning to suspect a voltage rail 
is  missing or the receiver is totally muted, however the NS1500 power  supply 
seems to be working correctly and appears to give the  correct voltage outputs.
 
Can anyone provide a circuit/schematic of the HT1500LH RF Unit Module  
please? or point me in the direction of any further information - before I  revert 
to drink!.
 
I just wish I had been allowed to take German at school 45 years ago  instead 
of Latin. After giving up Racals the R&S and AEG/Telefunken  receivers here 
are infinitely more challenging and, to me, represent  the peak of late 
Analogue design. (The Racal peak was the RA1779,  RA1784 and RA3701.)
 
All info gratefully received. Thanks,
 
Pat G3YFK