Lightening damage on a Sony MHC-RG40 Mini Hi-Fi Component System
Lightening damage on a Sony MHC-RG40 Mini Hi-Fi Component System. Lightening apparently entered the system from the ground side of the main AC power cord. Upon inspection a power transistor (2SA1932) on the transformer board was burned. I replaced the power transister and an open 3 meg resistor. The system still does not work. I'm stumped. I checked the voltages around the power transister and main transformer. The transformer voltages and resistances check okay with a know good transformer. However, the voltages around the power transistor that I replaced (Q911, 2SA1932) are lower than those on the schematic. The base voltage should be -39.8 but reads -27.5. The emitter voltave should be -39.2 but reaads -26.9 and the collector voltage should read -50.2 but reads -43.8. I just don't know where to go from here. When I plug the system into the wall plug, the on/off button doesn't do anything and the display only lights on the right side.
I would appreciate if someone can give me a clue as to where to look next.
Thanks
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