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Beware of old AntiStatic foam

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intabits:
Unforunately, I wasn't aware of this previously, and maybe others aren't also...

Among my most prized possions are my first two microprocessors - a pair of Signetics 2650s with ceramic packages and gold plated pins, that I bought new back in 1976.
I dug them out a few months ago, just to make sure that they hadn't been lost, but I didn't take a closer look at them until today.
Not only had the antistatic foam they had been stored in for 40+ years decayed to dust, it had corroded the pins of the chips away in the process. The gold plating was no obstacle.





I found some discussion of this:-
https://vintage-radio.net/forum/showthread.php?t=131907

So to save them, (after DeOxiting and cleaning them) I'm thinking of soldering them to  machined pin IC sockets like this:-



It looks like the pins on these ceramic packages are not part of the leadframe, but separate pieces that are welded(?) to the frame. I hope they are welded, rather than soldered, so that they won't come adrift when I solder them to the socket.

Before I do this, does anyone here have any better suggestions for saving these chips?
A PCB adapter board with header pins maybe? (they don't need to be plugged into any existing socket, so the pinout can be anything)

Zero999:
I've seen it where I work. Have you tried cleaning them with isopropyl alcohol? An ordinary detergent may help, but make sure it's properly rinsed and dried, before storage, or usage.

Modern polyethylene anti-static foam doesn't decompose like this and there are polypropylene anti-static packages which are pretty good. If you can't get that, then how about putting the ICs in ordinary sockets, to protect the pins and packaging them in silver or black ESD safe bags?

Refrigerator:
Old foam deteriorates and gets either dry and crumbly of wet and sticky, looks like yours was the latter.
You see this often in old cars where the headliner foam deteriorates as well as the foam suspension in speakers.
I think it's humidity that causes this.
Also make sure you plug the socket into a breadboard to keep the pins straight when soldering.

RoGeorge:
Have you tried using a pencil-eraser to clean the pins?

It cleans almost everything, and it can be cut or pierced to clean any facet of almost any shape.

Refrigerator:

--- Quote from: Zero999 on March 21, 2021, 11:56:05 am ---Modern polyethylene anti-static foam doesn't decompose like this and there are polypropylene anti-static packages which are pretty good. If you can't get that, then how about putting the ICs in ordinary sockets, to protect the pins and packaging them in silver or black ESD safe bags?

--- End quote ---
Cleaning with vinegar might be an option as well i've seen people clean battery leakage (and other corrosion) from PCB's this way.

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