Rotel RA01 Amplifier Repair (With Audio Tutorial)

Fault
Power supply T5 Amp protection fuses blown.

Right channel Audio output transistors short circuit
Q620 2SD1047 & Q622 2SB817 transistors replaced with Sanyo Genuine originals.

Emitter resistors R630 & R632 0R22 - ohm 2 Watts open circuit, replaced

Resistor R626 220- ohm 1/4 Watt burnt out, replaced.

Low voltage power supply circuit Zener diodes coated in conductive and corrosive Glue.
Glue removed and contaminated components replaced.
D905 & D906 18V Zener 500mW.

Speaker protection relays replaced 24 DC Coil DP/C0 fixing intermittent loss of sound.

User controls and switches cleaned with De-Oxit to ensure noise free operation.

Bias for each channel set to 4 millivolts.

Amplifier fully tested working correctly.

Dim bulb current limier circuit

   • Light Bulb Current Limiting Circuit (...