Bill Epstein Messages: 1088 Registered: May 2009 Location: Smoky Mts. USA
Illuminati (2nd Degree)
Fried a resistor on the driver stage of the 45 amp the other day. Bad driver tube took it out. Or bad CCS mosfet took out the tube, or... Have had a problem with the turn-on surge of the B+. Even damaged the other channels mosfet. In looking over the problem and replacing the bad parts at the WSOTT meeting Saturday, Steve suggested implementing a switch on the B+. With a .01uF 2kV cap across the terminals. Last night I installed it. On the center tap connection to ground. Just a SPST 250 VAC, 10 amp rated toggle. Powered up and let the filaments warm up for a few minutes, then closed the switch. No flashes or crackles, which I had previously.