Tube Amp Archive

With both volume controls set max CCW, measure resistance from chassis to pin 4 and pin 5 of the 6N7. Connect the meter directly to the tube socket. What have you. Thanks; there is no 6N7 on the unit I am servicing. See my schematic. There is "infinite" resistance at the grid of V3 to ground, on mi...

Stevem wrote: ↑Mon Sep 29, 2025 9:16 pm Share this at Schematic heaven .
They will put it up there.

I don't see how to submit items to Schematic Heaven. Can you help? Thanks.

sluckey wrote: ↑Mon Sep 29, 2025 10:31 pm I think this is the original from the Gibson Amplifier Master Service Book...

Yes, I used part of that one which matched the unit in for service to create the correct schematic for the untouched unit I was drafting, since mine was so different.

V3 should be connected like this... Yes, well aware. See my note on the schematic? And i'll copy this from what I posted to another member: "Seemingly so, but yet, I checked, and checked thoroughly. Did you see my note about that on the schematic? I had checked for any voltage on the grid: there wa...

V3 cannot operate properly without a ground reference for the grid. Seemingly so, but yet, I checked, and checked thoroughly. Did you see my note about that on the schematic? I had checked for any voltage on the grid: there wass none. I had re-verified that there is no ground reference. Since no gr...

I created a schematic for an unchanged 1938 Gibson EH-150, never serviced, no orig parts changed, untouched innards that is different than the two versions I can find on-line. Where should I post? Sure could help someone trying to restore one like this that had been modified over the years. Attached...