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Attaching wires to an ICs on a mainboard (breakout board?)

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I need to attach some wires to a couple of ICs inside a vintage computer and hope to find some vias I can solder them on. Failing that, what's the best way to attach wires without being messy (e.g. soldering directly to the IC pins) or soldering underneath and having long wires go all the way around the computer's PCB? One of the ICs is socketed (24 pin, not sure if it's a normal or "narrow" type, but can check -it's a PAL22V10), the other one is a 20 pin IC (74F244) which I assume is a standard 20-pin DIL type IC.

I've heard of "breakout boards" which I was expecting to be small PCBs with a long-legged IC socket, allowing for the IC to go on that board, and plugging it into the computer's IC socket, then getting solder pads/holes for attaching wires to any of its pins, but contrary to what I'd expect I haven't had any success finding anything like that online. Suggestions?

That’s not really what a breakout board is. They usually just lead out the IC footprint to pads of better pitch for hand soldering.
If you could get an unpopulated one, there are IC sockets with long legs you could use with it, so long as the computer’s ICs are socketed.

It isn’t so bad to solder to the IC leg if the mod is permanent. The GALs are programmable arrays, so keep the dwell time low.
The chips aren’t replaceable.

Temporary or permanent wires?

If it's permanent, and if the wires are routed neatly, it's not that messy to go directly to pins. Remember you can do it on either side of the board, since I assume you're talking about through-hole tech. The backside is often easier than the front for many things, and may not be visible at all when you're done.

--- Topside permanent mods ---

Soldered chip: Clean pin shoulder with fibreglass brush, solder Kynar wirewrap wire direct to the pin.
Socketed chip - find a high clearance turned pin socket,  solder Kynar round the increased diameter base of each pin, then insert it between the chip and the board socket. 

Both are often neater than trying to pick up the signals at vias as the vias can be all over the place.

In both cases it may be helpful to use two SIL strips of turned pin sockets as a plug and socket to allow the mod to be disconnected without soldering or cutting wires - you can solder wires into the socket end of a turned pin SIL strip to use it as a plug.  Superglue the socket side of the connector down somewhere convenient e.g. on its side on top of the soldered chip, or to the side of the turned pin socket under the socketed chip

Don't run wires from the bottom side unless you can keep them short and protect them where they go round the board edge.  if there's space to do the whole mod bottom side, OK but otherwise best avoided.

When it comes to mounting mods, 3M foam VHB tape is your friend - there's nothing worse than a mod board coming loose and shorting out,

I decided to do it simple and soldered wires carefully directly to the TTL chip's pins.
I read somewhere about using flux to ease soldering so I tried it out for the first time, putting a little bit (Weller LF-25 "soldering grease" -I hope I got the right type as I read somewhere about certain types with acid in them used for soldering water pipes etc. and not electronic components, which can in time destroy PCBs and components) on the IC pins and quickly soldering the wires. The solder seemed to flow easier, so I guess I did something right  ;)

For the PAL chip I didn't want to solder directly on to the IC and I didn't have any wire wrap wire (truth be told I don't have any experience with wire wrapping), so I simply stripped a regular wire, tinned it ever so slightly and carefully wrapped it around the uppermost part of the IC's leg, finally covering it with a heat shrink tube (see image attached). I don't know if this is the best method though as I can't seem to get it to stay tight (it moved around when I moved the wires as I connected the other ends to their respective connectors).
I had a quick look for "kynar" on eBay and found this. Are we talking about an insulated type of wire which is to be stripped, then the un-insulated wire is to be wrapped tightly around the IC's leg as you suggested, and will sit tightly unlike the regular electrical wire?

I gave up soldering a wire to a via as they were so small -it'll probably be hard to get a strong connection and I fear the wire may get loose and rip up the via.

As for turned sockets -did you that I get a wire wrapping socket like this, wrap a wire around the socket pin in question, "sandwiching" the wire between that wire-wrap socket and the existing socket? That sounds like a good idea except I found out that there is very little clearance above the socketed IC (there's another PCB a few mm above, partly covering the IC), so I can't raise it any further. But would wrapping Kynar around the IC's leg, then re-inserting it into its socket do a similar job?

I looked up 3M VHB tape but here it seems to be available only for industrial use, besides there are many different types of VHB tape -which one are you referring to? Is it a special type of tape or will any "foam" type of tape hold loose circuit boards/modifications in place? I probably have to look for something else, or see if they have it on eBay or something if that's what will work.


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