Lisa jittery screens

From: Jeffrey H. Ingber <jingber_at_ix.netcom.com>
Date: Tue Dec 31 16:42:00 2002

Bingo!

That fixed the jittering on both machines to a large degree. I hit the
pots with a quick burst of contact cleaner and that finished off the
problem completely. The display is as good as new.

Thanks a bunch!
Jeff


On Tue, 2002-12-31 at 07:47, Chandra Bajpai wrote:
>
> This happened to my Lisa, after consulting with some Lisa experts found
> the fix was really easy. Take the top cover off the Lisa to expose the
> Lisa Video Board. You'll see 3 small Pots on top of the video board,
> over time the contacts oxide to cause the jitter....now with the Lisa on
> and with a small screw driver, *slightly* adjust each pot to wipe away
> the oxidation..return the pot to the original setting.
>
> -Chandra
>
>
> -----Original Message-----
> From: cctalk-admin_at_classiccmp.org [mailto:cctalk-admin_at_classiccmp.org]
> On Behalf Of Jeffrey H. Ingber
> Sent: Monday, December 30, 2002 8:47 PM
> To: cctalk_at_classiccmp.org
> Subject: Lisa jittery screens
>
> I have two different Lisa machines and both have a jittery display (one
> 1.2AMP PSU, 1 1.8 AMP PSU). I've followed the instructions in the Sun
> Rem. guide to adjust the power supply output. This works immediately
> after the adjustment, but the problem gradually comes back over time. I
> adjusted both machines around the September timeframe and the jitters
> have back on both machines. I'd like to get both of these machines in
> top-shape so I can have them running at my New Years party =)
>
> Before I go through the adjustment again, is there anything else I
> should be checking? I've also tried adjusting the V.Hold, but this
> doesn't seem to make a difference. Maybe I'm not using a precise enough
> adjustment?
>
> Thanks,
> Jeff
>
>
>
Received on Tue Dec 31 2002 - 16:42:00 GMT