After troubleshooting found bad protection relay .
Relay replacement solved the problem.
Technical Pluses – simplicity, easy to reach components.
Minuses – low grade protection relay TYPE MU2U unusual size they used in manufacturing process.
Author: Provo Electronics
Parts and repair service for audio /studio HI-FI equipment. Mcintosh,Sansui, Kenwood, Fisher,Pioneer, Marantz, others HI-FI gears. Repair service for vintage audio gears. Audio HI-FI equipment repair and restoration service. Arcade games repair. Metal detector Minelab, Whites, Garrett repair , service.
Seattle area.
Case# 456234.Pioneer SX-950. Protection relay not clicking.
Case# 456234.Pioneer SX-950. Protection relay not clicking.
Outputs -OK.All voltages from power supply – ok.
Replacing capacitors on power supply section and 2 resistors 1.3 kohm (green on picture) on protection control board solved the problem.
Case # 342553. Mcintosh 754 amplifier. Missing left channel.
Case # 342553. Mcintosh 754 amplifier. Missing left channel. 09/27/2022
After troubleshooting found protection relay not working properly.
Relay replacement solved the problem.
