hello: check or measure if you have 180v in C412 of 4.7mfx250v when giving power ... if you don't have them measure if you get the 12v starter to the T402-Q402a-Q402 .... shake measure when it gives power if it arrives the source start pulse to the base of the Q802 ... measure when giving power q, voltage of the + b appears in the C821 in source .. this must be 125v in C821 ... and see if it reaches pin3 of the fli-bak ... check vertical stage ... check fli-bak and yoke ... check if they light the filament in the tube ... review welds on all the pins of the fli-bak ... and source ... Cheers!!