Faced with a small handful of these (from a Korg Lambda), what's the best way forward? I've thought of a) bridging the missing tracks/pads with wire, and b) getting some replacements made, but presume that is going to be pricey. Unless I could cover costs by flogging spares.

I have three or four in this condition. Looks like they've been soldered with a trowel at some point:

What's on the other side of that board?

It looks like there are a lot of completely unsoldered pins on a 40 pin chip holder or somesuch. It also looks like there are missing pins. If there genuinely are not supposed to be connections there, then that part of the board can be left alone.

In any case I'd give the boards a gentle brush with a soft artists paintbrush soaked in Isopropyl Alchohol. Where track has gone lay fine bare wires along the path (I often use individual strands of lightweight flex), and solder.

If there is any movement in the components dot try to make a rigid connection but leave just enough slack so that the components can move without stressing the repair.

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It wasn't me!
(Well, actually, it probably was)

Quote Folderol:

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What's on the other side of that board?

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It's a single-sided PCB, the other side carries, as you rightly surmise, a 40-pin IC socket and a few zero-ohm jumpers.

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It looks like there are a lot of completely unsoldered pins on a 40 pin chip holder or somesuch. It also looks like there are missing pins. If there genuinely are not supposed to be connections there, then that part of the board can be left alone.

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Perhaps I should have explained first - the original IC socket was damaged, and the IC had been part-soldered in at one corner - there was also a wire bridging one of the broken tracks but it had worked loose.

The state of affairs in the photo is after I had removed the broken socket and de-soldered the 40 pads. Or, what was left of them. Someone had been there before and caused the damage you see in the pic - I was careful not to make it worse. If it looks like the new socket is not fully connected, you're right - I soldered a couple of pins to keep it in place while I decided what to do with the broken pads.

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In any case I'd give the boards a gentle brush with a soft artists paintbrush soaked in Isopropyl Alchohol.

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At the risk of sounding stupid, what does that do? Would it simply remove the surplus gunk, or strip the coating back to the copper?

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Where track has gone lay fine bare wires along the path (I often use individual strands of lightweight flex), and solder.

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I was thinking that already - having looked further at potential costs of making half a dozen replacements, I am probably not going to bother.

That board is not exactly dense, and I think you could kitchen table cook a few easily enough with the aid of one of the toner transfer setups and some ferric chloride.

Do you have a laser printer (And ideally a laminating machine)?
Plenty of free PCB cad packages out there of varying quality.

Failing that, see if there is a 'hackspace' in your area, they usually have the tools for this, and some even have PCB routers that make this kind of thing really easy.

Regards, Dan.

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Audiophiles use phono leads because they are unbalanced people!

I'm short of basically everything, but you're probably right. I reckon a DIY setup would be a good thing to have so I'll have to do a bit of thinking on that.

Assuming everything's at standard pitch it'd be pretty straightforward to fab the boards. Are the edge connectors and the IC socket standard too? Can you post a pic of the other side?

Do you have a service manual for the Lambda? Sometimes they include PCB artwork or at least component layouts including the PCB traces beneath. These could be used to generate new artwork for etching. Alternatively as the board is quite simple you could probably recreate the artwork from scanning it, particularly if it were completely desoldered and so would sit flat on the scanner.

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Original artwork and unique devices inspired by vintage technology http://www.thisisobsolete.com

Quote jellyjim:

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Assuming everything's at standard pitch it'd be pretty straightforward to fab the boards. Are the edge connectors and the IC socket standard too? Can you post a pic of the other side?

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Righto. The above offender, plus another less dodgy one:

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Do you have a service manual for the Lambda? Sometimes they include PCB artwork or at least component layouts including the PCB traces beneath. These could be used to generate new artwork for etching. Alternatively as the board is quite simple you could probably recreate the artwork from scanning it, particularly if it were completely desoldered and so would sit flat on the scanner.

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I have the schematics, but not a full service manual, so no artwork. I did think about scanning it though.

I could fab you a few easy enough if you like? I've got lots of etching to do over the next few weeks anyway. I'd leave you to populate them though as I don't have time to source the hardware. I'd ask you for cost of materials obviously but anything else would be at your discretion PM me if you want.

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Original artwork and unique devices inspired by vintage technology http://www.thisisobsolete.com