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These RCA's can be undone by stupid stuff, most heat-related. I just got done with a CTC16 where a wire run on top of PW700 next to a 6GU7 tube socket pin, was arcing only under full AC power and smoking the cathode resistor. Visually, the resistor was the prime suspect until seeing the little flashing arc under the socket. The resulting potpourri of reeked of classic RCA fly arcing and made the set's owner think his NEW flyback just burned up.
So all looks well on that oscillator PW, even the tube and socket? Its just not normal for an synchroguide oscillator to NOT run. The coils could not have been adjusted out so far as to shut it down I suppose.
Maybe Im grabbing at straws here but see what is external to the circuit, causing issues DC voltages are coming *TO* the stakes. on the osc PWB. Start with resistance at D, to see if maybe a shorted AFC diode (which are over on the vert PWB) should be very high like 780 K ohm.
H-275 vdc, A -386 vdc, F-6.3 vac, D - zero dc and 40v p-p ac, G and E both close to 260 vdc. If any cap gets leaky like C604, C605 and C606 its curtains.
If I was not out of VK memory, Id post the schematic for clarity.
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"When resistors increase in value, they're worthless"
-Dave G
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