Re: Lisa doesn't power on - power lights up for 1sec, speakerclicks, then off.

From: Ray Arachelian <ray_at_email.domain.hidden>
Date: Thu, 01 Dec 2005 12:08:29 -0500

Yeah, from what I see everything seems to point at the power supply. It's likely that plugging in one of the bad I/O boards stressed out something in the power supply. Other than this, the only thing that's in common are the CRT, video board, LisaLite and cables in the chasse.

I originally had the following which worked, except I could never get the floppy drive to function.

Lisa motherboard (regular Lisa2 - external parallel port)+cage+Parallel Port card
Lisa 2-10/XL I/O board with 88 ROMs + the extra on board IWM. H-ROM CPU Board
Lisa Chasse with LisaLite adapter + 1 3.5" floppy. 1.8A power supply.

I tested:

a 2nd motherboard
two I/O boards - one with a visibly damaged 6522 - both with some corrosion from leaked battery packs.
two more CPU boards.

one known bad 1.2A power supply which I tested last night to be sure it's dead. It does provide the +5V trickle to the COP421, but doesn't turn on as the 1.8A one does.

So my next steps are to take apart the 1.2 and 1.8A power supplies and see if any caps or components are visibly damaged and check the polarity of any diodes after discharging their caps so I don't get shocked.

I guess I could eliminate the LisaLite too by unplugging it, as well as memory boards.

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Received on 2005-12-01 09:10:43