Hello Everybody!

      Yes, I worked today (saturday)...but it's such crappy weather here today
that it's not a big deal.

      Anyways, I just wanted to share a little tip for a band-aid that got our
butts outta the wringer, that I did on the prototype boards that I had talked
about on Friday...the ones that I was waiting on the LSI parts for.

     Got the SMT done on 10 boards yesterday, and this morning we were going
to stuff the through-hole and wave these puppies. The boards are a PCI plug-in
product and there's two 32MB SIMM's that are socketed on the board. We had the
PTH almost all stuffed, and tried to stuff the SIMM sockets in the board and
discovered that the footprint had gotten screwed up! Can you believe it? A
72-pin SIMM socket footprint got messed up!?! Let's see...SIMM sockets have
been around since I was a lil' squirt haven't they? How does one screw that
up?

Anyways, there's two sections of pins for each SIMM, somehow it was laid-out
where that gap in the center was too wide and of course the pins in the socket
didn't line up with the holes in the board. There was a small panic spooling
up, because these were pretty hot prototypes (but aren't they all?).

Some feverishly urgent calls made to the design house and to the designer who
did the lay-out...what good that was doing at this moment I've not a clue, the
boards were already built...(but at least now I know who to give the 20-lashes
with a length of solder wick to) and there was some hastily made suggestions
for me to epoxy or glue the sockets to the board somehow, and then run jumpers
from the pins on the socket to the holes on the board...that to me seemed like
taking the scenic route to get where we wanna be. Plus, I didn't think the
board would look too hot with 144 wires on it. One other thing,Tran, (my best
rework operator) woulda' had me drawn and quartered if I had her wire up those
sockets. She's pulled some real magic for me a time or two, and I surely
didn't want to upset her!

So what I wound up doing was getting some lead clippings from the drawer on
our axial prep machine, and then had Tran solder one to every other pad on
each side of the SIMM (THAT, she could deal with, not jumper wires...) and
leave them long enough so they could be bent slightly and conform to the
messed-up hole pattern on the PCB. We first asked our customer if it was a
problem that the SIMM would be soldered into the board, they said not at all,
just as long as they could power the board up and it had memory... WHEW! That
was a close one!

I know it's a simple tip, but the first reaction everybody had was to hurry
and rush to get some more fabs made with the right footprint, pay mucho bucks
for a prototype quantity of boards on a quick turn, and still wind-up delaying
when the customer would get their "babies". As things turn out, it wound up
causing us a little extra work, but the customer will still get their boards
monday like we promised.

Just a little something to store in the ol' memory banks (no pun intended) in
case it ever happens to you...

-Steve Gregory-

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