Cleaning an 11/34?

From: Christian Fandt <>
Date: Wed Nov 3 22:03:50 1999

Hi Chuck,

I've got an 11/34A in a H960 tall rack and your plan sounds just fine so far.

You indicate the foam pad is decomposed. Must be the front filter you mean.
It disintegrates into little itty bitty pieces that are sometimes hard to
clear out. I suggest you carefully remove that glop as much as possible
before you remove all the boards so that as little as possible of that
stuff falls into the slots. It can be quite difficult to completely clean
out a slot in which that soft stuff has been entrapped -trust me. Use a
very small good quality brush (one that doesn't shed its bristles) with
rather stiff bristles and vacuum the slots carefully. Inspect with a bright
flashlight or some other bright light which will let you see clearly into
the slots just in case something has dropped in over the recent years.
Pain-in-the-neck intermittents can be brought about with crud in the slots
which somehow gets up onto edge connector fingers. One o' them Murphy's
Laws I think.

Also the cable retaining clamp bar on top of the PSU area at the back of
the box has a foam pad that turned into the most gooey goo on mine. I just
cleaned it off with mineral spirits after doing a preliminary scrape. Bits
of that garbage are _especially_ unwelcome to drop into a slot.

I just vacuumed my boards using a natural bristle brush to dislodge dust.
Note I said natural instead of plastic/nylon bristle. Less static
electricity is generated using the natural bristle on the CMOS type boards
(like the MS-11L). It was during summertime when I did this too -more
humidity in the air to help dissipate static. Looked rather fine after that.

Upon the date 06:33 PM 11/3/99 -0800, Chuck McManis said something like:
>Megan, you recently recovered an 11/34. Any suggestions on cleaning one? I
>think I'm going to need to get all the gunk out of the 11/34's case which
>includes a completely decomposed foam pad, and what appears to be dust from
>the last 20 years. This is my plan for it:
> 1) Pull the boards and grants (noting location)
> 2) Vacuuming out the case, using a damp cloth on the
> front to clear up the front panel.
> 3) Washing the boards, (except for core mats)
> 4) Verify the PSU.
> 5) Install enough boards to get ODT to talk to me
> and then work it one set at a time until I can
> boot from the TU-60.

I can't yet get ODT to say much to me on my machine. I've got to resurrect
this project yet again in the next week or so. Probably something simple
and dumb on my part. I've got to carefully smoke out the problem and try to
get it solved.


Nice find for yourself Chuck! Good luck.

Regards, Chris
-- --

Christian Fandt, Electronic/Electrical Historian
Jamestown, NY USA
        Member of Antique Wireless Association
Received on Wed Nov 03 1999 - 22:03:50 GMT

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