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ChrisNomad, about how much bias did that 46B need. I’ll have to hook up a temporary plate current meter on this one so I can get 50-100mA of idle current per tube when amp is keyed, but no drive. The one I have here had about 15v of bias, but they used 1A diodes. I’m currently waiting on new tubes. But 15v seems kind of low. Tube arc’ed, took out 20Kv @2A rectifier ( doubler circuit) I made new with 10A diodes. No glitch ( it has one now). Bias not fused, ( it is now) 15A fuses, I changed to 10. One was blown. I had to check and make sure I still had continuity on windings. Plate choke was resonant ( nice burn mark a third of the way up). Amp was ugly. New chimneys with 3/8” holes. They used a countersink to do 1/4” holes.

[QUOTE="Crusher, post: 754166, member: 3746"] ChrisNomad, about how much bias did that 46B need. I’ll have to hook up a temporary plate current meter on this one so I can get 50-100mA of idle current per tube when amp is keyed, but no drive. The one I have here had about 15v of bias, but they used 1A diodes. I’m currently waiting on new tubes. But 15v seems kind of low. Tube arc’ed, took out 20Kv @2A rectifier ( doubler circuit) I made new with 10A diodes. No glitch ( it has one now). Bias not fused, ( it is now) 15A fuses, I changed to 10. One was blown. I had to check and make sure I still had continuity on windings. Plate choke was resonant ( nice burn mark a third of the way up). Amp was ugly. New chimneys with 3/8” holes. They used a countersink to do 1/4” holes. [/QUOTE]

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