Quote:
Originally Posted by Sparky
If you can measure the B+ current, ...Total current (playing at good volume). Divide the voltage needed to drop, by the max current, and you have your resistor value.
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It's more complicated than that, as the current thru the rectifier looks like a series of short but high current pulses, of low duty cycle. One spike per 60Hz cycle. Because the rectifier is topping off the first filter capacitor at every positive peak of the 60Hz powerline. Between these peaks the radio draws all the B+ current out of the filter cap.
A resistor of around 22 ohms (use one rated for a few watts) would be good as a start. Increase or decrease to get the B+ where you want it.