[MrFixr55]

Hi Philco4Me,

Switch off or switch on it doesn't matter. You will have to turn the switch on as part of the test. Have one of the knobs on on the volume control / switch and avoid touching the chassis.

Do not be working on a metal bench. Remember that this is a hot chassis set. Depending on the switch being open or closed and the "polarity" of the plug, the chassis touching ground could blow the breaker or your heart. Seriously, be careful. On hot chassis and warm chassis (Chassis connected to B- through a cap) sets, I always rewire so the switch is on the "Hot" side (Rectifier and 50C5 side) and that the chassis or B-, 1st Audio) is directly connected to neutral. Replace the cord with a polarized cord (Wide pin is neutral).

Consider replacing the selenium rectifier with a 1N4007. Put a 1A MDL fuse in series with the hot side of the power cord, before the switch. The voltage drop on a selenium rectifier is higher than that of a silicon diode but at this voltage, it is not critical.

Hope this helps.