From: David Tetzlaff <>
Date: Wed, 9 Nov 2011 18:51:32 -0500

> There must be another one

Not necessarily. The main 5A fuse probably covers the whole power supply, and the audio amp is probably powered by a DC tap off of that. So it wouldn't need it's own fuse (as it probably doesn't have it's own PS). If there was a fuse, other than the ones accessible on the exterior, it would probably be on the audio circuit board, maybe with axial leads soldered on if not in the little clip holders.

But my guess is it doesn't have a separate audio fuse, and something else is your problem. When the projector is on can you hear any sound from the speaker at all? A pop, a little hum, some white noise? If it's dead stone quiet the first thing I'd suspect is that the either the speaker is bad, or has become disconnected. If you can trace the leads to the speaker back to the circuit board, and you have any other kind of speaker you can temporarily connect by touching wires to the output points that would tell you if the amp is working at all. If you can verify that indeed no signal whatsoever, no juice at all, is coming from the amp, then I'd guess the output stage of the amp is blown. (Not a DIY repair...)

On the other hand, if you can hear some kind of residual noise from the speaker, just not sound from the film, that would point to a problem on the input side of the amp, again either a connection or the input stage of the amp circuit. The first thing I would suspect there is the volume control... The pot could be worn out, or the wiper broken off. Does anything happen if you work the volume control back and forth quickly several times?

good luck,

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Received on Wed Nov 09 2011 - 15:51:42 CST