transistor madness

[Enzo]

I may not be old and good, but I sure am good and old...

[MarkusBass]

I rebuilt it using the schematic below. There are a few differences. But when rebuilding I noticed the pot was in backwards!!

But I don't think it's working right. In fact it's not. it's supposed to be a treble booster. But it just cuts. When I turn it on it's a cut! With a tiny hum behind it. GGGGGGARAARrr!!

I pulled out the germanium 2SB77 and put in a 2N3906 just cuz I knew I could. Got similar results. Actually it was a bit louder and clearer. But still a cut. Oh man! Wut is goin on! Just crappy wiring?? Could my soldering just be this bad???

Please be aware that you selected very special and very old design. It has +9V of the battery connected to the ground and it uses old PNP germanium transistor. As a consequence, electrolytic capacitors are all inverted. The circuit will not work with other transistor without modifications. Such transistors can still be purchased of ebay I think.

Mark

[olddawg]

Read this please.... It's basically the same info they used to have in the front of the ECG Catalogue, but in color...
PNP or NPN? Page 66