hi ampmaker, i'll try and answer with what i know,
mains fuse and ht fuse both ok, red power light on.
no output at all, no hum from speakers.
basically, i switched on tonight as usual, waited about a minute before
switching standby switch on, but it didn't make any sound, then it worked
for about 3 seconds and stopped again, it did this again after wriggling the
different connection leads on a zoom g2 box, then died again.
switched it off and took the amp out of the combo cabinet to see if the valves were glowing, and found two ax7 preamp valves not glowing.
put two spare valves in, and these glowed (all 5 valves glowing).
still absolutely no sound/hum from speakers.
thanks for your interest, any ideas?
cheers, jonah.