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HiFi (Chifi) tube amp build - but my own design.
#67

Well, found muh culprit. After using socket test adapters and finding voltages all ok, swapping 6V6s, no avail, swapped the 6GH8a with a good Phillips 6U8a and bingo! Clean as can be! Junk Jap made 6GH8 tubes! Well, I kinda think they may all be junk. Anyway, the couplers are fine. It hadn't been sounding very good and with one output tube having to be flipped or moved to get it to light up, figured the sockets were the main problem. Wrong! Stupid tube failed! Same with the china made ones. Don't last. That said, I'd observed some weird effects putting my meter/oscilloscope probes on the lower 6V6 G1 (cathode side of the phaser), so I swapped in a 10k stopper (left the 1K on the other tube) and that stopped the weird effects/oscillations. Read that needed to be done on some circuits using the 6U8/6GH8 driver instead of 7199 in AK. Well, must be something to that since it seemed necessary in this adaptation. I can elaborate if anyone would like the reason for this.

If I could find the place called "Somewhere", I could find "Anything" Icon_confused

Tim

Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44


Messages In This Thread
462ron - by 462ron - 10-15-2024, 09:07 AM
RE: HiFi (Chifi) tube amp build - but my own design. - by TV MAN - 06-07-2025, 11:18 PM



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