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RE: now I am really puzzled ......

Sorry, thought I was. I mentioned in the previous post that the voltage at the end of the 20k resistor started going down after turning up a
the power part way. You said that was to be expected and that it would come back up when the plate was conducting. i was telling you that it just kept going down until I reached full mains voltage with the variac. At that time I measured 283 vdc at the distribution panel for B+. That is a terminal strip with all tabs connected. If I disconnect the opt from that strip I have a B+ of 400vdc (B+ to ground), but when the opt is connect and the node for the 26 tubes is connected to B+ too the B+ drops to 283vdc (B+ to ground) and the voltage reading between ground. Bias is set by the cathode rersistors (820 ohms for 26, 1200 for 45.) All of these readings were taken with just the left channel connected to B+.
I will try going back and reading it between the plate and the cathode and see what I get. I will also measure the other two voltages you asked for.


Edits: 04/26/16
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