JUNO 106 LED failure

[n00bzill4]

Hey there,

The LEDs for the sawtooth or square waveform select have both stopped working at the same time, the switches still function as they should though. I thought it was strange that both should drop out simultaneously unless if one went it would mean the other wouldn't work either? Or is there another obvious suspect?

Cheers

[rhino]

Welcome to the board!

If ONLY those two LEDs do not light:
1) both leds failed
2) bad copper trace near them

If those leds AND CHORUS I and II, 4', 8',and 16' are dark:
1) IC 15
2) bad trace

Try jumpering the bad leds - one at a time - with new ones.

[n00bzill4]

Thanks very much Rhino for the welcome and advice,

I've cracked open the case and I'm pretty sure I've found the fault, the D55 track appears to have corroded through between the chorus and sawtooth LED. Please bear with me as I've only got minimal experience with this type of thing..... I have conductive paint but I'm not sure this would work as the track is insulated? Worth giving the track a scrape and giving it a try? If not I'm guessing the fix would be to solder a wire fromm D55 on the chorus LED to D55 sawtooth LED?

[n00bzill4]

[n00bzill4]

Well I decided to throw caution to the wind, scraped back the insulating layer with a blade and there was definitely a break.



I had some conductive paint I'd used for a motherboard voltage mod years ago, I figured at worst I could just scrape it back of again.



Voila.



Maybe this might be of use to somebody that needs to do a small repair but isn't confident with a soldering iron.

Cheers

[rhino]

Nothing succeeds like success!

Good work!

[cornutt]

Interesting. Never seen that happen on a 106. It must've had something spilled on the panel at some point.