23 Mar
2010
23 Mar
'10
5:27 p.m.
----- Original Message -----
From: "John Foust" <jfoust at threedee.com>
To: <cctalk at classiccmp.org>
Sent: Tuesday, March 23, 2010 8:14 PM
Subject: Re: Leaving computers on... (was Re: Disc analyser news update)
At 07:06 PM 3/23/2010, Dave McGuire wrote:
Could be something simple like dirt in the landing zone of the HD head,
works fine when running but shut the system down and the head gets stuck. I
have had systems that worked with noise coming from circuits with capacitors
boiling off that did not work when shut down and turned back on. You also
have heat/cooling cycles from turning equipment on and off that snap bad
solder joints on parts (especially stuff made around the time they switched
to non lead solder).
In my experience, on/off cycles kills equipment
much faster than
long "on" times.
Is that biased by the experience of failures that appear when
equipment is powered-on?
One would seem to be shaped by simple MTBF, the other by some
sort of electrical or mechanical surge.
- John