13-10-2021, 09:39 AM
Even valve gear I'd only use a lamp limiter on very dodgy looking series heater live chassis, or valve TV.
Cold inspection etc as Trevor says ^^^^.
Some transistor PAs can be damaged by low HT. A SMPSU will attempt to maintain o/p and take high currents on a variac.
An RCD is of no use. A low as possible fuse according to power rating, even 100mA or 500mA.
Check HT and speaker drive point of transformerless push pull.
Cold inspection etc as Trevor says ^^^^.
Some transistor PAs can be damaged by low HT. A SMPSU will attempt to maintain o/p and take high currents on a variac.
An RCD is of no use. A low as possible fuse according to power rating, even 100mA or 500mA.
Check HT and speaker drive point of transformerless push pull.
