Xref: utzoo sci.electronics:2320 comp.sys.ibm.pc:12314
Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!ames!hao!oddjob!gargoyle!ddsw1!karl
From: karl@ddsw1.UUCP (Karl Denninger)
Newsgroups: sci.electronics,comp.sys.ibm.pc
Subject: Re: A static problem--solutions?
Message-ID: <778@ddsw1.UUCP>
Date: 23 Feb 88 15:31:54 GMT
References: <959@pbhyc.UUCP>
Reply-To: karl@ddsw1.UUCP (Karl Denninger)
Organization: Macro Computer Solutions, Inc., Mundelein, IL
Lines: 45
Summary: Check your *LINE* power

In article <959@pbhyc.UUCP> jdf@pbhyc.UUCP (Jack Fine) writes:
>
>Static electricity would seem to be the problem although I don't know this
>for sure.  Micro computer systems (IBM PC XT) from certain users will 
>suddenly blank the screen and freeze up requiring a cold boot to get
>started again.  We have tried various things such as static sprays, static
>dischargers, better grounding and so on but the problem seems to persist.
>It doesn't happen to everyone and not to all building locations.  It seems
>to be happening in one or two very specific areas of the building and it
>comes on suddenly.  A person sitting working never noticing a problem
>before will have a screen die and system lockup with data loss.  Then it
>begins to repeat on the same person.  Replacing systems and other pieces of
>hardware doesn't seem to help and as I have said the static solutions do
>not stop the problem.  Someone sitting a couple of feet away doing the same
>things (apparantly) will not have a problem.  Sometimes the problem goes
>away and we have attributed it to one of the things we have tried.  I am
>beginning to wonder though if that is the case or the cause of the problem
>simply went away.  Anyone else run into this kind of problem?  Anyone find
>a viable solution to it?

Check out the power coming into the system unit itself.

To do this cheaply (without renting a line analyzer; these tools do exist)
you can move the CPU in question to a place where you know it is not on the
same circuit.  In fact, move it to a place where there is another, correctly
functioning, CPU and plug in to that power.

If the problem disappears, you have a really terrible power source on that
PC....  the problem could be interferance in the RF band, spikes on the
line, or nearly anything else that disturbs clean power distribution.

The fix, in these cases, if you cannot move the equipment or power feed, is
to buy a "line stabilizer" or a full-blown on-line UPS.  Your garden-variety
surge-suppressor will likely not help (although being as cheap as they are,
it is worth a try).

From your description (only in some areas of the building, and it comes and
goes) I am lead to believe that you might have a problem with a noisy piece
of electrical gear on the same branch circuit as your problem systems.
If the offender can be found, you simply move it to another branch circuit
or move the computers (if the offender cannot be moved).

----
Karl Denninger		       |  Data: +1 312 566-8912
Macro Computer Solutions, Inc. | Voice: +1 312 566-8910
...ihnp4!ddsw1!karl	       | "Quality solutions for work or play"