Скачать или смотреть Marantz PM7200 Amplifier Repair (With Audio Tutorial)

Fault
No Audio output, speaker protection relays not turning on.

Power supply failure +VB 56V / -VB 56V voltages missing on connector 1217.

Power supply removed and T500mA Fuses checked, reference numbers
1215 / 1216 both fuses open circuit.

Rectification Diodes checked component reference 6206 1N4003 short circuit.

Fuses & rectification Diodes replaced restoring correct operation.

Due to the age of the Amplifier and the known issue of dry solder joints that that develop overtime with Marantz Amplifiers all circuit boards re-soldered.

Speaker protection relays also replaced to avoid any future issues with intermittent loss of Audio or distortion at low volume due to oxidised relay switching contacts.

Part Number 1-1393258-7TE - Brand Connectivity
24 V DC Coil DP/CO

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

DC offset adjusted and Bias set for Class AB & A modes set.

Amplifier fully tested, working correctly.