[PDP8-Lovers] Re: how to clean a PDP8/A, dishwasher?

From: Richard Erlacher <edick_at_idcomm.com>
Date: Mon Dec 17 07:08:08 2001

I'm not absolutely sure about such things, but, having had to sit through the
annual ESD classes year after year in order to maintain my cert's when I was in
aerospace, ISTR that the "old" TTL was ESD sensitive to a point, and I seem to
remember something about TTL having a threshold of 2KV for ESD sensitivity.
That suggests that while it's not as likely to go poof at the slightest ESD, you
can't "ZAP" it without harming it. Since the "ZAP" that you feel when reaching
for the doorknob is >50KV, typically, the 2KV would hardly be noticed.

As for that dishwasher, what does it do that thorough washing in water that's
quite hot, and brushing with a brush and using detergents that dissolve flux,
etc, as is often done in PCB manufacture, particularly where rework is
concerned? The "DRY" cycle is unwarranted, but the rest of the operation, so
long as one takes some pains to avoid gettin residual garbage already in the
dishwasher in the connectors, etc, is not likely to hurt the board or its
components, unless you have a leaky relay or some such mechanincal part that
needs protection from water. The tape on some unductors may have a problem with
water, too, so a visual inspection might be warranted. Hot water, soap,
scrubbing, etc, are all common in cleaning and maintaining PCB's.

Dick

----- Original Message -----
From: "Johnny Billquist" <bqt_at_update.uu.se>
To: "PDP8-Lovers" <PDP8-Lovers_at_dbit.com>
Cc: <classiccmp_at_classiccmp.org>
Sent: Monday, December 17, 2001 1:30 AM
Subject: Re: [PDP8-Lovers] Re: how to clean a PDP8/A, dishwasher?


> On Sun, 16 Dec 2001, Pete Turnbull wrote:
>
> >
<snip>
> > ... Allison's warning about ESD is quite real. Don't
> > even think about a feather duster; at least, not if it's a synthetic one.
>
> ESD should never be ignored, but in the case of computer from the 60s and
> 70s, ESD is really not an issue. We don't have CMOS, we have old style MSI
> TTL here... It is not ESD sensitive. You can literally zap those
> circuits, and they will work just fine.
>
> Johnny
>
> Johnny Billquist || "I'm on a bus
> || on a psychedelic trip
> email: bqt_at_update.uu.se || Reading murder books
> pdp is alive! || tryin' to stay hip" - B. Idol
>
>
Received on Mon Dec 17 2001 - 07:08:08 GMT

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