Well, I tested the 128k's T1 Flyback transformer in another Mac and worked perfectly. SO that's good. But installed in the 128k it does not seem to get power at all. That leads me to suspect the next prior component in the circuit, the Q3 (or HOT). I tested a known good Q3 transistor in the 128k and still no power to the T1 flyback. Using Prof. Lee's schematic, tracing the circuit backward I see the next component is T2. Is it possible this isolation transformer failed somehow with no visible signs? Feeding the T2 is a +12F? signal via resistor R7 and a +5V signal via a small driver transistor Q6 that is fed via a resistor R26. The +12F seems to coming from L1 toroid. I don't know the source of the +5V. I'm in no man's land here as I do not know what to inspect next that is most likely responsible for power failing to reach the T1 flyback transformer. Remember. everything else works ... the computer starts up, loads floppies, seems to be sending power to the CRT connector, and all the voltages test correctly off the logic board. So it would seem the power supply is working perfectly. Some obscure component is broken somewhere on the way from the power circuit to the horizontal circuit. HELP!
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