Article View: comp.sys.mac
Article #20574Re: a different kind of SE screen quirk
From: David Hull
Date: Tue, 20 Oct 1987 23:10
Date: Tue, 20 Oct 1987 23:10
38 lines
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2541 bytes
In article <1660@mit-amt.MEDIA.MIT.EDU>, (Adam B Rosen) writes:
> When scrolling through
> a large document, say in Word (any version) or downloading text via modem,
> as the print scrolls up the screen the Mac makes a very faint 'pulsing'
> noise with each line....
In article <458@sdacs.ucsd.EDU> wade@sdacs.ucsd.EDU (Wade Blomgren) writes:
> An acquaintance of
> mine, upon hearing the description of this problem, surmised that it could
> actually be the 68000 processor (or the ROM?) doing the screaming, as the
> tightly looped set of ScrollRect calls is executed. He had seen a similar
> thing in a lab full of AT&T boxes. (Meaning that there was some fairly common
> activity that started those processors humming).
Well, my Mac SE does this too. I just noticed it about a month ago
(I've had the SE for about six months now), so I don't know if the noise
started just recently or if it has been there all along.
I'm pretty sure that it's the power supply making the noise. We had a
couple of Sun 2s at work that had the same kind of problem--executing a
program would cause it to make a loud buzzing noise. Replacing the
power supply cured the problem. I think that as the CRT and the 68000
draw current during a scroll it causes the power supply to make noise.
> Regardless of the cause of this particular glitch (avoidable or not),
> I am not impressed with the QC on the Macintosh SE.
I agree. I've had mouse clicking problems, disk ejection problems,
the loud fan, and now this. My screen doesn't normally wiggle, but I
can make it do so if I hold my hand over the fan outlet on the back.
Anyway, the noise isn't a catastrophic problem. As you say, the fan
practically drowns it out. But annoying, all the same.
-David
--
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David Hull TRW Inc. Redondo Beach, CA
...!{uunet,cit-vax,trwrb}!wiley!david
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Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!mnetor!uunet!wiley!david From: david@wiley.UUCP (David Hull) Newsgroups: comp.sys.mac Subject: Re: a different kind of SE screen quirk Message-ID: <1506@wiley.UUCP> Date: Tue, 20-Oct-87 19:10:50 EDT Article-I.D.: wiley.1506 Posted: Tue Oct 20 19:10:50 1987 Date-Received: Fri, 23-Oct-87 02:10:09 EDT References: <1660@mit-amt.MEDIA.MIT.EDU> <458@sdacs.ucsd.EDU> Reply-To: david@wiley.UUCP (David Hull) Distribution: na Organization: TRW Inc., Redondo Beach, CA Lines: 38 Keywords: screech, hum Summary: Power supply makes noise