• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

ARC VT-60 Cloned :-)

Some pictures of my spare PCB.
 

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I'm thinking if I should follow the PCB and find out source follower/ccs that was supposed to be used here or go back to the orginal RLC version. Any experience or suggestions?
I'm sure you've figured it out by now, but mine had a DN2535 bodged in on the top of the board, not unlike how ARC does in the vt-100. I had some small boards made for it that will fit in the bodge location instead. They haven't gotten here yet, so no testing has been done. If my re-bodge attempts work out nicely, the next thing on my radar is adding some trimmer bypassed resistors on the cathodes of the output tubes so they can be adjusted individually.

I'm not sure what your board is supposed to have, I've seen a few different configurations.

Mainly I'm trying to stoke the fire of this thread as I progress through modding my original, and I'm looking for as many opinions and options as I can gather. I want this thing to be bulletproof once it's running. 🙂
 

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If I can ask one more question, it was mentioned by 6a3summer but I didn't see much talk about it, how are 6550s (and maybe kt120s if anyone's tried it) holding up with the high grid leak resistors?

Has anyone swapped them for lower max Rg values, and if so, can the 6922s still drive the outputs reasonably?