Now how did that fault occur ? I "interrogated" Peter as to how it was connected in his shack and found it had been wired to a two input speaker box along with a 2 Metre rig. I handed it back to Peter with the comment, "when you wish to dispose of it I would like first refusal please".
That night conditions on the 3.62MHz BoatAnchor net was particularly bad so I used the repaired IC-756 Pro11 and was amazed at just how well the various noise reduction/signal processing cirsuit worked. Some TCW and some cambric sleeving fixed the missing track and I put it back together. I eventually got brave enough to remove the main board after unplugging many leads and there was a burnt track, the earth track for the speaker and external speaker socket.
I did have to modify it with an external RF probe and to correct the bias on at least one of the germanium transistors. I was using a signal tracer I bought from Tandy when they first opened stores DownUnder many years ago. I soon discovered the audio system was fine but nothing was getting to the speaker or the external speaker socket. My first plan of attack was make some sense of the circuit diagrams and then trace the audio path from the detector to the speaker. I soon worked out it was working, the S meter was waggling round and when I pressed the PTT it was transmitting. The original owner brought it to me to fix and it seemed to be "dead". It is quite old now (2004 I think) but it has very advanced noise reduction and signal processing. About the first of February 2016 the display on my fancy Icom IC-756 Pro11 suddenly went blank.
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