egg wrote:
click image to enlarge [about the hum-pot].
Kind of obvious, but if you are mixing any pre-amp and power amp that has a hum-bucking pot anywhere, don't ground the 6.3 VAC center tap on the PT so as not to short out half the heater winding when the hum pot is turned to one end or the other... easier to see than explain!
I always use the hum pot slider ground, typically in the preamp, and never ground the PT 6.3 volt CT.
Cheers,
Roger