[comp.sys.mac] My Mac is "fuzzing"!

sobiloff@thor.acc.stolaf.edu (Blake Sobiloff) (05/24/89)

First, a word of advice: never use an ultrasonic humidifier in the same room 
as a computer with a fan...

OK, here's the situation: Within the past two months my Mac will occasionally
start "fuzzing" the pixels on the screen.  I mean that everything starts jumping
a couple of pixels back and forth for about a second, then clears up.  This
only seems to happen when it has been on for a while.  I live in a rather
dusty environment, and thinking that it could be overheating caused by dust
coating the inside, I opened up my Plus and used compressed air to blow all the
dust and *calcium deposits* off the boards, tube, etc.

It didn't really help.

What is the next step?  Is this indicative of something major about to go wrong,
or does it just need a better cleaning?  BTW, my setup is a Mac Plus with a 
Kensington System Saver, and a Jamine DD70 which my Mac sits on top of (I've 
elevated the Mac off the drive an inch to see if the heat from the drive was 
causing problems, but no luck.).  Thanks in adavance...
							Blake

-- 
********************************************************
* Blake "Hey, where's *MY* fancy .signature?" Sobiloff *
*             sobiloff@thor.acc.stolaf.edu             *
********************************************************

t-jacobs@wasatch.utah.edu (Tony Jacobs) (05/24/89)

In article <2260@thor.acc.stolaf.edu> sobiloff@thor.stolaf.edu (Blake Sobiloff) writes:
>OK, here's the situation: Within the past two months my Mac will occasionally
>start "fuzzing" the pixels on the screen.  I mean that everything starts jumping
>
>What is the next step?  Is this indicative of something major about to go wrong,

Fuzzing is a sign that the connectors that go from the analog board to the
monitor yoke are not making good contact.  It may also be a sign that you have 
a cold soldier.  The connectors for those same plugs are likely sources. 

Try cleaning the pins on the connector (both male & female sides).  If that
doesn't do it you can try resoldiering some of the pins on that same connector.



-- 
Tony Jacobs * Center for Engineering Design * UofU * t-jacobs@wasatch.utah.edu

hal@krishna.cs.cornell.edu (Hal Perkins) (05/25/89)

In article <2260@thor.acc.stolaf.edu> Blake Sobiloff writes:
>First, a word of advice: never use an ultrasonic humidifier in the same room 
>as a computer with a fan...

You don't need to go that far, just use distilled water.  My humidifier had
a specific warning to avoid anything other than distilled water if there were
computers, VCRs, or other delicate electronics gadgets in the area.

You do read the instructions, don't you?   :-)

Hal Perkins                hal@cs.cornell.edu
Cornell CS

cleeland@rex.cs.tulane.edu (Chris Cleeland) (05/25/89)

In article <2260@thor.acc.stolaf.edu> sobiloff@thor.stolaf.edu (Blake Sobiloff) writes:
>
>OK, here's the situation: Within the past two months my Mac will occasionally
>start "fuzzing" the pixels on the screen.  I mean that everything starts jumping
>a couple of pixels back and forth for about a second, then clears up.  This
>only seems to happen when it has been on for a while.  I live in a rather
>dusty environment, and thinking that it could be overheating caused by dust
>coating the inside, I opened up my Plus and used compressed air to blow all the
>dust and *calcium deposits* off the boards, tube, etc.

Well, I have one of the last 512KE's to roll out of Apple, and the same thing
has been happening to me lately.  However, I don't have a hard-drive; I just
have a Racal-Vadic 2400V modem on top, an APPLE external 800K next to it, and
no fan.  It sits by itself on an otherwise open desk.  The room is also not
very dusty -- just your average apartment dust!

Any techies have any ideas?

Thanks in advance (and all that other garbage)...
-- 
Thanks
Chris Cleeland, Tulane University

Disclaimer:  I haven't said anything worth not claiming!!!

gillies@m.cs.uiuc.edu (05/25/89)

> OK, here's the situation: Within the past two months my Mac will
> occasionally start "fuzzing" the pixels on the screen.  I mean that
> everything starts jumping a couple of pixels back and forth for about
> a second, then clears up.

My Mac II AppleColor Monitor did this (horizontally jumping) during
warmup, for a many minutes at a time.  There was a secret warranty to
have this fixed.  I took the machine in once, and they replaced the
analog board.  The problem temporarily disappeared.  Now the problem
lasts only a few seconds, about ten minutes into warmup, so I decided
to live with it.  After all, it is much better to have a 5 second
problem than a many-minute problem.


Don Gillies, Dept. of Computer Science, University of Illinois
1304 W. Springfield, Urbana, Ill 61801
ARPA: gillies@cs.uiuc.edu   UUCP: {uunet,harvard}!uiucdcs!gillies

kehr@felix.UUCP (Shirley Kehr) (05/26/89)

In article <370@taniwha.UUCP> paul@taniwha.UUCP (Paul Campbell) writes:
<In article <1898@wasatch.utah.edu> t-jacobs@wasatch.utah.edu (Tony Jacobs) writes:
<>monitor yoke are not making good contact.  It may also be a sign that you have 
<>a cold soldier.  The connectors for those same plugs are likely sources. 
<   ^^^^^^^^^^^^
<
<Cold soldiers can really be a problem, both Napoleon and Hitler has this
<problem when marching on Russia :-)                             ^^^

However, Napoleon and Hitler themselves probably could use a little of
that cold now. :-)

Hey, only 14 articles today? Are you all on vacation?

Shirley