NAD Amplifier Repairs

NAD 3130

NAD 3130 Stereo Amplifier NAD 3130 Stereo Amplifier

This one was burning a 560 ohm resistor near the output transistors. It needed the output 3055\2955 drivers and the temp sense transistors replacing. Quiescent was too high after the repair so I had to change RX1 for a 530 ohm.

NAD 160a

NAD 160a Stereo Receiver NAD 160a Stereo Receiver NAD 160a Stereo Receiver

One channel was lower than the other. A faulty capacitor was found in the tone circuit. I also replaced the capacitors on the PSU board 470 µF 50 V & 100 µF as they had been hot for a while.

NAD 3130

The output was distorted, as though the o\p stage had expired. Turned out to be the smoothing cap on the -ve supply to the dual IC used in the tone\filter circuit, it was shorting. There are several of these low quality caps around the PCB, could have been any of them!