Color classic headphone/speaker out not working correctly

[Verault]

Pretty sure C8 is supposed to connect to that via next to the negative capacitor pad and not where the bodge runs, also what’s the pin touching something here in this area?

Those pads were damaged so the caps are run to the next trace off the original contact. Those are fine and not the issue.

 

[jajan547]

Those pads were damaged so the caps are run to the next trace off the original contact. Those are fine and not the issue.

Maybe further under the chip near the center there is a bridge between the two pins.

 

[Verault]

I took the chip off yesterday and I can see with a scope pretty far under it. I really dont see a short. I think its elsewhere on the board.

Or the chip is internally shorted.

 

[jajan547]

What a strange issue I’ll look more on my end too.

 

[Verault]

This gets stranger.. Maybe I have found nothing. I just checked the dead LC575 board (which now is missing the DFAC2 and the Audio jack. The pads on the board where DFAC2 used to be show continuity between pads 37 and 38!

Do you have a color classic? I could really use the insight of someone testing on a real board.

I also traced out continuity from pins 37/38 and they go to the Microphone jack not the headphone jack.

the schematic has the JAck right (J2) but it calls it "PHONES JACK" which is wrong.

 

[jajan547]

This gets stranger.. Maybe I have found nothing. I just checked the dead LC575 board (which now is missing the DFAC2 and the Audio jack. The pads on the board where DFAC2 used to be show continuity between pads 37 and 38!

Do you have a color classic? I could really use the insight of someone testing on a real board.

I also traced out continuity from pins 37/38 and they go to the Microphone jack not the headphone jack.

I have one with the mystic mod and a CC2 with the stick board I have two color classic logic boards but had to have both sent to a friend because there was some pretty severe cap damage to the pads and battery damage on the ram pads and LS chips on the other plus no sound lol

 

[Verault]

I have one with the mystic mod and a CC2 with the stick board I have two color classic logic boards but had to have both sent to a friend because there was some pretty severe cap damage to the pads and battery damage on the ram pads and LS chips on the other plus no sound lol

Any luck?

 

[jajan547]

Any luck?

Could honestly be a bad chip it's not uncommon on Color Classics, and you did verify this chip worked fine on the donor board? You can bypass the external speaker I forget what to do but I know that if you bypass it and still no sound through the headphone jack then I suspect it's the Jack.

 

[Verault]

I think you are right. Any idea where I can find a new/replacement chip?

 

[jajan547]

I think you are right. Any idea where I can find a new/replacement chip?

Check L2 that could cause it that or L1

 

[Verault]

I did check the inductors. no breaks, they are ok.

 

[jajan547]

I did check the inductors. no breaks, they are ok.

No I don't mean breaks I mean L2 usually goes bad worse case scenario

 

[Verault]

right but if ther eis continuitt the inductor is good right?

 

[jajan547]

right but if ther eis continuitt the inductor is good right?

so my apologies it L1 but seems they'd be okay if there is continuity.

 

[Verault]

I realize I left this thread hanging. I was able to source a couple spare sound chips for the color classic. A new one fixed a the issues I have with the board as well as having a spare for the furture. I need a similar chip for my LC III which works fine but has no sound at all. That sound chip seems to be unobtainable.

 

[jajan547]

I realize I left this thread hanging. I was able to source a couple spare sound chips for the color classic. A new one fixed a the issues I have with the board as well as having a spare for the furture. I need a similar chip for my LC III which works fine but has no sound at all. That sound chip seems to be unobtainable.

Which sound chip, post a photo

 

[Verault]

this other forum thread gives the info, Im not alone in searching: https://tinkerdifferent.com/threads/need-sound-chip-344s1033-a-for-lc-ii.874/