Rotel RB970BX MK2 Power Amplifier Repair (With Audio Tutorial)

Fault
No Audio from the right channel.

Previous repair work had been undertaken by the owner prior to the Amplifier arriving in the workshop.

The following issues were found and corrected.

Speaker protection fuse holder only making contact with one end of the fuse.
Fuse(s) replaced wrong type installed should be T6.3A.

Link connecting the base of Q631 to the rest of circuit not soldered in place.
Q623 2SD600K Open circuit, replaced.

Damaged solder pads in the output stage repaired.

Stereo / Bridge mode switch removed and cleaned with a fibre glass pencil and De-Oxit.

Bias for each channel set to factory setting 8 millivolts.

DC Offset on each channel checked low at 7-8 millivolts.

Power Amplifier fully tested, working correctly.

Dim Bulb Tester
   • Light Bulb Current Limiting Circuit (...