Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Esquirefreak on February 28, 2022, 12:32:32 pm
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Good afternoon/evening.
I'm currently working on a parts-left-over-amp because why waste anything.
At initial startup I had issues with negative DC voltage on the MV pot from the PA tube bias supply. My first time building something with a MV so I had not taken that in to consideration.
I've since changed the design to cathode bias. Not because of the DC leak issue, but because all my other amps have got fixed bias already and I wanted something even more raunchy. The build is inspired by the bright channel of a 6G3 sans trem. It really sounds quite alright.
However, I'm having a hard time letting go of the issue and thought about how to resolve it. In theory, that is, for the sake of learning.
Would this (very rough drawing) suffice? If not, where did I go wrong?
Best regards,
Max
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Looks OK to me. However, I'd put the 1.5K grid stopper directly to the tube grid rather than the MV wiper.
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Yeah, that makes sense. Would look better as well, to put the grid stoppers between pin 1-5 on the sockets.
Thanks for input.
/Max
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Sorry in advance if I've got this wrong, but should your PI plate resistors be between B+ and the PI plates? Again, I might be reading your schematic wrong. :icon_biggrin:
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Sorry in advance if I've got this wrong, but should your PI plate resistors be between B+ and the PI plates? Again, I might be reading your schematic wrong. :icon_biggrin:
Most all plate resistors are connected between plate and B+. :wink:
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Ah, I knew I screwed up somewhere! You are, of course, absolutely right that the plates should attach to the OTHER end of the resistors.
/Max