Some of these FBT's plugged in. The connections would toast up.
Also the mother board & module connectors went cold a lot. Dont
forget the frame grounds....
It doesnt show one but this is about the time they switched to
4-lead caps. An open leg will kill the HV.
The SCR is for HVSD. Pull it to eliminate BUT use a variac, you may
have too much HV. Start it at abt 70VAC.
With the tripler input unhooked you should get a healthy 1/2" arc
at the FBT out. These were not FBT eaters. Only ones I changed
were badly burned from the bad connections.
73 Zeno
LFOD !