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RE: Can you post a schematic? (nt)

Posted by cpotl on March 18, 2017 at 14:31:40:
"The resistor lowered the voltage to the tube so the current decreased."

I think he's saying he puts the resistor in place, and then measures the voltage drop across the resistor, and also across the choke (first choke, if I understood correctly). He then uses Ohm's law for the resistor, and for the know DCR of the choke, and comes up with the seemingly discrepant results for the current.

Many things could be going on involving the AC component across the choke causing complications, as has been suggested. Especially if it is the "first choke," which I would take to mean the one closest to the rectifiers. There will be a lot of AC across that choke. Who knows how the voltmeter, set to measure DC voltage, will respond when a small DC voltage has a large AC voltage superimposed? It could depend a lot on the specifics of the particular meter that is being used.

Of course another possibility could be a leaky smoothing capacitor. But on balance, I would expect the AC superimposed on DC complications in the measurement to be the more likely explanation.

Chris