Quote:
Originally Posted by RevennaFox
I don't have any fusistors, but it should be safe to replace it with a 1Ω resistor in series with a fuse, correct?
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Technically yes, as long as the resistor has long enough leads to prevent scorching the PC should the horiz output transistor short. Don't use a carbon in any case. Sony used to use ceramic coated resistors as fusibles. This prevented scorching anything nearby, eliminated the "crack" noise metal films made when they blew out, and made no smoke. If a customer hears a loud crack and smoke comes out, they think the TV is junk at worst or cheaply made at best.
Quote:
Originally Posted by RevennaFox
I'm still a little confused why the HV only spikes when the horizontal deflection coil is connected, but hopefully that problem will disappear after I reign in the power supply issues.
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The HV isn't spiking with the yoke connected, it's acting normally. By disconnecting the horiz windings, you inadvertently lowered the HV which kept it below the safety shutdown point. The horiz windings of the yoke are part of the tuned circuit that includes the flyback, so the TV will only reach maximum (normal) HV output if the horiz windings are attached.
Once you repair the LV regulator, the HV will return to normal with the windings connected. This assumes your B+ measurement is taken while the TV is actually running. Once it shuts down, the B+ would rise anyway because the STR is bypassed by that big white resistor. With the TV in shut down, there would be no load across the resistor and the voltage would rise to the bridge voltage (160ish).
Now if the TV was otherwise running normally and you disconnected the horiz windings, you would get a vertical line down the middle (maybe) and the HV would drop in half at least because you detuned the circuit.
John