Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ncar!ames!killer!linimon
From: linimon@killer.DALLAS.TX.US (Mark Linimon)
Newsgroups: comp.misc
Subject: Re: Looking for Computer Folklore
Summary: firsthand
Message-ID: <7090@killer.DALLAS.TX.US>
Date: 9 Feb 89 06:36:48 GMT
References: <799@n8emr.UUCP>
Organization: The Unix(R) Connection, Dallas, Texas
Lines: 22

In article <799@n8emr.UUCP>, lwv@n8emr.UUCP (Larry W. Virden) writes:
> I was at a DECUS
> conference about 6 yrs ago when a system programmer was laughing about
> programming a Dec machine to seek around on a disk drive enough to cause the
> cabinet to rock.

I saw either this incident or a similar one -- firsthand.  PDP-11/20, Ampex
add-on disk, "custom" (phew) controller, 1973.  Some late-night programming
bums had tortured the diagnostic program to "full seek at switch register
speed."  After that a quick binary search produced the resonant frequency
of the machine.  At one point the electronics in the disk had crashed
and Ampex was called, and we were fiddling with it to find the resonant
frequency.  About this time the Ampex field service guy walked in
and was _really_ unhappy.

Disk was OK, though, it was built like a tank.

Mark Linimon
Mizar, Inc.
uucp: {convex, killer, texsun}!mizarvme!linimon

disclaimer: 1973 was a long.....time.....ago....