TV/VCR/Stereo Troubleshooting/technics su v303


my technics su v 303 output transisters  (a1264 & c3181) were shorted and i replaced with the same.  After working for 5 hours the amp gone into standby mode. on computer drive display, thermal LED not flashing. Please help me in this regard and also suggest the equivalents for the above transisters. And also suggest me whether the computer drive, thermal sensor, protection circuit be disconnected so as to use only amp section. Please kindly help me Sir.

Did you properly grease the transistor replacements when installing them?  It requires very careful silicon heat grease to make certain there is good transfer of heat to the heat sinks once in operation again.  Please check that first as the transistors will heat quickly and burn out if not able to keep the case temperature down to prevent thermal breakdown inside the transistor junctions.

Hope this helps.  

TV/VCR/Stereo Troubleshooting

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