[turretslug]

As only too typical with things of this nature, watch for high value resistors under high potential stress being not quite what they were- there have been several differing detail iterations of carcase PSU design, my on-the-way-to-the-granulator rescue dog had 5x 6M series resistors as EHT feedback (one other version has a single big 30M resistor here), one of these had gone O/C, resulting in a small, bright, hummy trace as the EHT power oscillator reached for the giga-volt gong using the ripply raw DC rail. A replacement VR37 restored normality, EHT rectifier and PDA multiplier seem none-the-worse for their ordeal.