Xref: utzoo comp.sys.amiga:23273 comp.sys.amiga.tech:1965
Path: utzoo!attcan!uunet!husc6!ukma!nrl-cmf!ames!amdahl!kim
From: kim@amdahl.uts.amdahl.com (Kim DeVaughn)
Newsgroups: comp.sys.amiga,comp.sys.amiga.tech
Subject: Re: A500 Spurious Reset
Keywords: Like, it's broke, dude
Message-ID: 
Date: 28 Sep 88 17:57:59 GMT
References: <1651@edison.GE.COM>
Followup-To: comp.sys.amiga
Organization: Amdahl Corporation,  Sunnyvale, CA 94086
Lines: 55

In article <1651@edison.GE.COM>, mfs@edison.GE.COM (Synth Hacker @ Lost in the Mountains, Inc.) writes:
>
> My A500 is reseting every now and then.  This happens just like I
> had done it from the keyboard; no Gurus.  Also, every now and then when
> I power it up, the caps lock LED flashes about once a second and the
> keyboard doesn't work.  Usually, if I power it down and wait a while,
> I can bring it back up and the keyboard works OK.
>
> Has anybody had a similar problem ?  Does anybody have any ideas ?

Yup ... I had identical symptoms on my 2000.  First time it happened was
about two months after I got it, and I thought it was a fluke, as it
didn't recur for quite awhile.  Anyway, it eventually got to the point
where it was happening every 20 minutes or so, and I had discovered
that if I unplugged/plugged the keyboard cable as soon as the led started
flashing, I would (usually) avoid the crash, and all was well for another
short period of time.  Quite annoying ...

One thing I finally noticed (once the frequency of occurance went up),
was that when it *did* happen, I was (usually) typing pretty *hard* on
the keyboard ...

I started tapping chips on the keyboard board, but couldn't isolate it
to any particular part or area.  Finally, close inspection of the solder
side of the board showed two really ugly joints.  Both on the keyboard's
oscillator crystal.  In fact, the xtal leads were actually a bit loose
inside the dull, gray, corroded looking joints.  I resoldered these two
leads, and poof! ... no more problems.

Also, I put a small square of double-sided adhesive foam tape between the
xtal and the board.  Seems that I've heard that xtal's can generate
minute mechanical/acoustic viberations, that can destroy solder joints
over time, and I figured that the foam tape may help to dampen any such,
if indeed they exist at all.  Can't hurt, anyway, and at least the xtal
is now firmly supported.


So ... I'd start looking for a loose component and/or a bad solder joint
on or around the keyboard.  I can't say it'll be the xtal's leads, but I
I'd sure start looking there!

Good luck tracking *your* problem down ... intermittents can be a real
bitch to find ...

Hope this helps out.

/kim


-- 
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