Note of info. To discharge hv, the proper way is a insulated screwdriver and jumper wire. Use blade of screwdriver for going to hv point. Connect jumper from blade of screwdriver to hv cage. You will hear a snap, or slight pop. Do this twice, as sometimes, they re-charge. Also, if there are hv caps accross plates of 2 hv rectifiers, and I think there is one, Dscharge that, as well. Variac won't stop hv from working. Just have to have voltage high enough for those circuits to work. Usually, a minimuim of about 100 volts ac in order for those circuits to work. You need a tube tester, mutual conductance preforred, to check tubes. Usually obtainable on e-bay for not alot of money.
