Quote:
Originally Posted by Guitarist28
I have noted that:
- volume control to the 2nd channel isnt working at he moment
- the EF86 has either blown or is not getting power as there is no filament glow
Any suggestions for putting a signal through the input rather than a guitar at this stage?
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You can check both volume control circuits doing a buzz test, I've drawn the input sockets as switched to ground when no jack plug is inserted in the schematic I did because a picture of one on the web seemed to imply switched jack sockets, basically the signals from input 1 and input 2 end up at pin 2 of the ECC83, there's not a lot between the sockets and pin 2, just the pots, the 470k resistors and the wiring.
You could feed the output from a sig gen into the inputs or line out from whatever or possibly an MP3 player.
If you could do some photos of the front and the back of the EF86 panel with the valve removed it might be possible to reverse engineer that part of the circuit as well.
Lawrence.