Lisa jittery screens

From: John Lawson <jpl15_at_panix.com>
Date: Mon Dec 30 20:29:00 2002

On Mon, 30 Dec 2002, Jeffrey H. Ingber wrote:

> I thought I'd add that the adjustments _do_ hold after the systems cool
> down. I ran the machines off and on during the week after the
> adjustments without a problem, even during extended on/off cycles - they
> just don't seem to hold very well over time.


   Well, speaking as an electronics geek, and, as I said, knowing nothing
Lisa-specific... all this points to accelerated aging of components
either in the power supply, (which I somewhat doubt, for no real 'reason')
or in the sweep and drive circuits of the CRT. Many old components have
an 'end-of-life' runup, and they exhibit the same symptoms (or
meta-symptoms) exactly as you describe.


  I of course must defer to the Lisa Mechanics out there. I'm basically
trying to make amends for that awful pun.



  Cheers

John
Received on Mon Dec 30 2002 - 20:29:00 GMT