MOTHA*&^%$$ just typed out a long post and it crashed adding schem
Anyway, Gibson Saturn GA-45RVT, 6L6 with broken pin installed wrong, blew fuse and 470 Ohm screen.
Replaced resistors and output tubes for testing.
Amp works, all features but only a few watts output.
V5A stage doesn't amplify, is it supposed to or just a phase splitter?
Also voltage on V5 pin 5 only 30v instead of 60v.
Amp varies greatly from schem between V4 and V5A, output pins 6 & 7 tied together, and instead of a mixing circuit theres an odd attenuator similiar in design to the schem, but different values.
Jumping across from V4 to V5A with a cap and amp puts out rated power.
Info:
All voltages close to schem value except V5 pin 5
No hum noise, minor ripple, so filter caps look decent.
Tone stacks really kill signal between stages, I guess the idea was to amplify signal to power amp with the 6FQ7.
Amp also has a few of those crappy caps used in Thomas Vox amp that need to go!
Anyway, Gibson Saturn GA-45RVT, 6L6 with broken pin installed wrong, blew fuse and 470 Ohm screen.
Replaced resistors and output tubes for testing.
Amp works, all features but only a few watts output.
V5A stage doesn't amplify, is it supposed to or just a phase splitter?
Also voltage on V5 pin 5 only 30v instead of 60v.
Amp varies greatly from schem between V4 and V5A, output pins 6 & 7 tied together, and instead of a mixing circuit theres an odd attenuator similiar in design to the schem, but different values.
Jumping across from V4 to V5A with a cap and amp puts out rated power.
Info:
All voltages close to schem value except V5 pin 5
No hum noise, minor ripple, so filter caps look decent.
Tone stacks really kill signal between stages, I guess the idea was to amplify signal to power amp with the 6FQ7.
Amp also has a few of those crappy caps used in Thomas Vox amp that need to go!
Comment