Software glitch malfunctioning faders or circuitry?

[ArKay99]

It sounds like there is a noisy multiplexer on the input of whatever adc is being used for those faders. The clue is when moving one fader, the next one's values move. Your best bet would be to take it to a recommended repair shop. JMHO.

[skillz335]

no chance im going to fix that. I have the technical ability of a chimp. thanks for the reply, I was hopeing to not have to take it to be repaired. Especially since the device has been discontinued. would it be cheaper to spend 500 bucks on ebay for a used 8800?

[ArKay99]

Originally Posted by skillz335

no chance im going to fix that. I have the technical ability of a chimp. thanks for the reply, I was hopeing to not have to take it to be repaired. Especially since the device has been discontinued. would it be cheaper to spend 500 bucks on ebay for a used 8800?

I doubt that it would cost $500 to fix. It could be something as simple as a dirty board interconnect. On the other hand it could be a board level issue because it's all surface mount. I don't know the device, but I seriously doubt it would cost you all that much to repair, IF you got it to a reputable shop.

[skillz335]

I really appreciate your help. after researching what you said, and if i understand correctly,. I wouldn't know where to locate or isolate any bad soldering, but would trying to clean the board with isopropyl alcoho help? I already tried compressed air. also if with the alcohol would I just need to clean in the general area of the faders or should I just go over everything on the circuit board?
Thanks again,
Aaron

[ArKay99]

Originally Posted by skillz335

I really appreciate your help. after researching what you said, and if i understand correctly,. I wouldn't know where to locate or isolate any bad soldering, but would trying to clean the board with isopropyl alcoho help? I already tried compressed air. also if with the alcohol would I just need to clean in the general area of the faders or should I just go over everything on the circuit board?
Thanks again,
Aaron

No. I was thinking there may be a connector linking sections of the mixer together. There could be a poor or 'noisy' connection carrying the signals used for the troublesome circuit. Sometimes a connector or pin will get tarnished and cause what's known as a high impedance connection. Sometimes just unplugging and re-plugging the connector will clean the connection by the scrubbing action of the two surfaces, the pin and the socket will clean themselves. You have to exercise great caution though as most of these circuits are static sensitive and you could zap a chip without knowing it and be in worse shape than what you started with. I wouldn't go cleaning the faders with alcohol as they have motors and grease/lube for both the track and the movement and the alcohol could dry out the bearings. Also, if you've already blown it out, I don't think you have a dirt problem.

My best advice at this time would be to get it in front of someone that knows about the device and has a schematic. It most likely has a lot of surface mount components and they take a different set of skills to repair than the older through hole componentry.

[skillz335]

cool thanks for all the help im going to do a bit of research now. and much thanks for the explanation. after some reading, Im off to find a shop.

[ArKay99]

Originally Posted by skillz335

cool thanks for all the help im going to do a bit of research now. and much thanks for the explanation. after some reading, Im off to find a shop.

Just a suggestion, why not ask for an estimate before you turn the gear in to repair? Go to a few shops, that way you'll have a better idea of who wants your money, and who wants your business.