Digitech GNX3 Problem

[techno-rachit]

Hi,
My friend's Digitech GNX3 is giving a serious problem..
The patches start changing automatically once the processor is started!!
I checked the switches for any shorts, I didn't get any
Then cleaned the microprocessor pins to ensure that there are no shorts on it due to dust....BUT THAT DIDN'T WORK TOO

Can please someone help me out with this problem???

Thanks and regards

[g1]

Have you tried the factory reset procedure? It should be in the user manual.

[soundguruman]

An educated guess is that there is an intermittent connection, maybe a bad solder connection, that is producing pulses in the control buses.
Maybe a bridged solder connection.
Or it can be a oxidized socket, that is holding a chip? I am not looking at your board.
But when the pulse occurs intermittently, the patch assign goes wild at random. Like you said, the switches seem like they are shorted......but are not. (the switch, when pressed, normally produces a pulse on a control buss to change patches.) It is as if the switch is being pushed by poltergeist.
Taping on the chips, boards, wiggling connectors and wires can sometimes help to narrow down the physical location of an intermittent. Also freezing components one at a time....re-soldering the circuit board is often a solution, BUT
what you might also have is a computer chip that is failing and UN-testable without complex equipment and or special knowledge of the systems.
Very often a bad chip will get hotter than normal, but how do you know what is normal?