NAD Audio Players & Recorders - Page 3 - Recent Questions, Troubleshooting & Support

Your problem might come up due to various reasons. Here are some points to start checking:

• Test if there is existing audio at the phones output (use a pair of headphones)
  
• Check that the speaker's cables are connected at the amplifier outputs
• Check that the 2 jumpers connecting pre out and mains (1 for each channel) are at the proper place.

Post me back with any news. In case of a problem or clarification or further details needed, don't hesitate to post me a reply before rejecting my answer.
If you are satisfied, rate my solution with the "thumbs" or (even better) add a testimonial.

Thanks and regards
Please kindly rate this solution
Stelios
direct fixya link: http://www.fixya.com/users/technical114

If you look inside the unit you might discover the reason why. My guess is that the belts have all turned to goo. Which is very common in tape decks.

Hello Hans
Have you checked the continuity of the primary windings of your amp's tranformer?. You have already stated that your amp went dead. If it is so, there must be some fault inside it, a fuse is blown, a shorted rectifier, a shorted filter capacitor, shorted output transitors or so. If so the mains fuse will blow out. have it happened in your amp?

Anyway the colour code cannot be predicted as Nad has different colour codes used for their primary winding input to their transformers. You just do one thing. The transformer primary have tappings in it, to input various voltage inputs, and that tapping are comming out in different colored wires. Measure the resistance of the winings, with a multimeter set to ohms range. One end of the winding will be direct, and the other end is tapped for different voltage inputs. The maximum resistance winding which you gets with respect to the common direct end will be meant for 240V, and next lesser meant for 220V. Leave the other ends free, and insulate its ends without touching each other, or touching in on the chasis. OK.

You may be lucky enough to find a rubber band that fits. But the quality rubber in a household rubber band is not as good as a belt made for the purpose, and variations in stretch may not affect your broccoli but may be audible in a cassette player. Watch tension and don't put on too tight because it could hurt delicate bearings. I have repaired many items this way also. Bon appetit and good listening! HOW TO REPLACE CASSETTE DECK BELTS INEXPENSIVELY OR FOR FREE

Hi, From your description, it sounds as if the noise is coming from the circuit that controls the display backlight. If I recall correctly, the C520 has an EL backlight just like the C521 (which I have one of). On the front of the circuit board, there should be a little yellow trimmer potentiometer that controls the brightness of the display. It may be that the noise will go away if the brightness is turned down some. If  the noise varies as you turn the controller, but doesn't go away completely, the backlight may need servicing.