From: liz@poppyrecords.invalid.invalid   
      
   Cursitor Doom  wrote:   
      
   > On Fri, 28 Nov 2025 11:37:56 +0000, liz@poppyrecords.invalid.invalid   
   > (Liz Tuddenham) wrote:   
   >   
   > >Cursitor Doom  wrote:   
   > >   
   > >>... Time for someone else more experienced with Uhers to take over   
   > >> methinks.   
   > >   
   > >I used to repair them many years ago.  if you live anywhere near Bath,   
   > >drop in and I'll try to help you.   
   >   
   > That's very good of you and I would - but unfortunately I left the UK   
   > many years ago. Thanks, anyway. :)   
      
   I'm sure I had the circuit diagrams for several of the Uher models - but   
   i have no idea where they are now.   
      
   I seem to remember the 2-transistor mic pre-amps had a rather clever   
   counter-intuitive volume control arrangement, which gave a wide range of   
   possible volume input levels.  The wiper was connected to the output of   
   the second transistor, with one end of the track going to the followiong   
   stage and the other end going to the emitter of the first transistor.   
   As the volume was turned down it increased the negative feedback around   
   the front end.   
      
   If you suspect the fault is in the AGC system, do you get an improvement   
   if you switch the AGC off?   
      
      
   --   
   ~ Liz Tuddenham ~   
   (Remove the ".invalid"s and add ".co.uk" to reply)   
   www.poppyrecords.co.uk   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)