I have a Wurlitzer 920 piano extension amplifier from 1954 in the shop.
The circuit is not your average garden variety amp. The screen grids of the output tubes are connect to the cathode of a 6SL7, which appears to be connected to a socket on the edge of the chassis. Possibly some accessory plugs in there and completes connections to provide screen grid power, but until I can see a diagram, it's just a guess.
Anyone know what goes in that socket and better yet, anyone have a copy of the schematic?
The circuit is not your average garden variety amp. The screen grids of the output tubes are connect to the cathode of a 6SL7, which appears to be connected to a socket on the edge of the chassis. Possibly some accessory plugs in there and completes connections to provide screen grid power, but until I can see a diagram, it's just a guess.
Anyone know what goes in that socket and better yet, anyone have a copy of the schematic?
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