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sockets.


donlcramer@...
 

All the talk of sockets prods me to talk of my one big socket story.

Around 1979 we started using Apple II computers in Display Research, Tek
Labs, as they were more versatile and cheaper than the usual Tek Labs
solution, the Tek 4051 series of desktop computers. (don't get me going on
the cost of DEC equipment either).

The Apple II (and II+) had an open archecture where it was pretty easy to add
custom interfaces as well as buy various third party boards for the more
usual functions. But the computers tended to crash regularly. This was due
to the cheap (Robinson Nuget--sp?) tin plated, face grab IC sockets they used
on all the ICs and to a marginal switching power supply which overheated when
the box was full of boards. In fact it was not uncommon for the power supply
to not start when cold, either.

So I did two things to every machine we bought. First, I ran them for about
30 days, then had the Bldg 50 prototype group (the old wirewrap group that
was next to the model shop) remove all the sockets and solder every IC in
except the RAM. The RAM got the nice double edge grab sockets that Tek used
(TI?), and later the tin plated Burndy sockets (those really dug into the tin
IC leads). Later machines got even the RAM soldered in.

The second measure was to add a Kensington fan module (which also included a
EMI line filter).

With those two mods our Apples ran flawlessly. We had seven when I left Tek
to go to Planar Systems. What I had heard later was that Apple socketed
everything because they used assemblers to perform initial troubleshooting of
the boards. That is, if it didn't work, a lower paid person shotgunned the
ICs first, and if that didn't work, the board went to a real tech. I think
this story surfaced when the Apple III computers came out and their poor
reliability was common knowledge. The standard operating procedure if the
computer wouldn't work was to lift the computer a few inches off the bench
and drop it to reseat the ICs and "fix" the intermittent. I have no first
hand knowledge of the IIIs myself.

I also remember that around that same time, there was much discussion at Tek
regarding IC socket technology, which types and when (or if) to use them. I
think this stuff was circulated through the Component News flyers. I have in
my library a nice booklet Tek put together regarding interconnects. It is
very informative.

Don