Digitech Synth wha reapir

[Bleed]

Hi all.
I'm trying to repair a broken Synth wah from digitech. I noticed that a component marked as "L5" is burned. Anyone has the same effect and can tell me which component is it, and its value? It's right on top, above the pots, near a 300uF capacitor.
Thanks

[Roobin]

L is normally an inductor...could you take a pic of the component?

[Bleed]

Lookin' closer, I'm not sure it's an L
Anyhoo, the part is completley burned, here's the photo
http://i217.photobucket.com/albums/cc70/Bliddo/Clipboard01-10.jpg

[axg20202]

It still might help if we could see the actual part you removed. Also, if it's I5 (or L5), then it's quite likely that there are at least 4 other similar components somewhere else on the board. See if you can find some markings on the components located at I1 through I4.

[Bleed]

There was nothing left, I just cleaned it up a bit, I thought it was the nearby capacitor, but it was fine.

[Bleed]

Also, if it's I5 (or L5), then it's quite likely that there are at least 4 other similar components somewhere else on the board. See if you can find some markings on the components located at I1 through I4.

Just a couple of inductors, L2 and L9, anche an empty L30 space...

[axg20202]

There was nothing left, I just cleaned it up a bit, I thought it was the nearby capacitor, but it was fine.

So the component has vapourised completely? Very odd, partcularly as there don't appear to be any component leads remaining at the pads - these don't just vanish into thin air. Are you sure this position was indeed populated and not just covered in gunk? Also, is this a double sided board - what's on the reverse side at this position?

[Bleed]

It's not just dirt, the pcb is a little burned in that spot... no idea where the component is gone.
Nothing on the other side of the pcb, just solder.

[axg20202]

Mmm, in that case, if you acquired this from someone else, my guess would be that someone before you has messed with it, either to perform a clumsy mod that involved removing this component and causing some local heat damage with the soldering iron in the process, or perhaps the user removed the blown component with a view to replacing it but didn't complete the job. Back to square one, your best bet is to open up a working one or have someone else do it for you, to see what should be here. That is assuming you can't get hold of the schematic.

[Roobin]

What's that little hole just above the left circle?
It could be jumper - there are traces below the pads. You could trace out that bit (it looks like the power supply section) and see what's missing.

[Bleed]

your best bet is to open up a working one or have someone else do it for you, to see what should be here. That is assuming you can't get hold of the schematic.

That's what I was hoping for by posting here

What's that little hole just above the left circle?

It's a pad linked to this missing L5 on the other side of the pcb.

It could be jumper - there are traces below the pads. You could trace out that bit (it looks like the power supply section) and see what's missing.

I'll check

[Bleed]

The left pad is connected to a 22uF capacitor, while the right pad is connected to the 9V power supply

[petemoore]

  The circles on the PCB where the mystery part was certainly look alike to the circles 'concentricating'...[word] under the adjacent electrolytic capacitor.
 Theory has it this was a capacitor.
 Also that something the freqk happened to it, and for some reason.
 [use above theory while examining the rest of the board while searching for non-capacitors above 'dual ring' board markings, for one thing], I get the idea it was a kirkpacitor which was beamed out of there.
 Overvoltage, AC voltage, and..reverse voltage are enough to blow a cap, and they're known to sometimes BLOW...like occupy a *much larger space in an instant [ie make a mess].
 Could be one of those things blue a cap out off it's legs...I'd think there'd be some leg left too...
 Maybe it worked a little and dude cleaned off the excess?...
 I'd search for evidence of 'moddery', and consider cleaning up any sloppy work [if any is found].
 Other than that I'd suspect something got into the cap from outside the circuit's box [ie rwong power supply attached], and replacing that cap might or might not be enough.
 Does it have reverse polarity protection diode? What is it's condition [measured].
 Then what else could have been RP'd, overvolted, or AC'd..there are other polarized components which may have seen the same destructive force applied, and have been damaged, just didn't decide to pop physically.
 

[Bleed]

well, there is an inductor marked with those circles, is the one right behind the power jack(you can see part of it in the photo)
The diode is ok.
I don't think the effect was ever opened or modded before. Still the lack of the burned inductor and the missing legs are pretty odd...

[Bleed]

Here's the inductor with the same marks
http://i217.photobucket.com/albums/cc70/Bliddo/Clipboard01-11.jpg

[petemoore]

  ok...looks like the first picture might show "L5" marked on PCB where mystery part was ?
  ie since I saw L2 mark on the board [under L2], I went back and looked at the first picture.
  You know how pictures can be when you want to try viewing from different angles and lighting [not saying post more pics, but can you see "L2" sort of clearly where the first pic shows print? or am I seeing things there...

[Bleed]

I see L5 on the first picture(missing component) and L2, pretty clear this time, on picture 2.

[Roobin]

Ah ok, now it looks like L5. But then why the huge burn inbetween the 2 pads? Did someone cut a trace?

[Bleed]

It was like this when I opend it. And I should be the only one that did...

[MikeH]

It was like this when I opend it. And I should be the only one that did...

Should be?  Was it working when you got it?  Did you buy it new?  Looks like a part has been removed.  There even appears to be some spattering from desoldering near the pads.