Re: Lisa 2 Repair

Those voltages are within tolerance.

The 2/10 I/O board never had batteries, but you do have corrosion on a memory board so that card cage may have had a Lisa 2 I/O board in it at one time. Check the motherboard and card slots for more corrosion.

That also brings up the possibility that the card cage doesn't match the chassis wiring. Since you have a 2/10 I/O board, you probably have a 2/10 card cage (back panel has an interrupt button but no parallel port), and the chassis should have 2/10 cabling (two ribbon cables in the drive cage area are different widths).

Since you have had varying symptoms on powering up (checkerboard and grey screen), I suspect you have a bad contact (at least). Clean the boards' edge connectors with a pencil eraser (don't erase the gold!).

It looks like your CPU board never had the capacitor added to C5. I doubt that is a problem.

The cut trace near C46 on the 2/10 I/O board is intentional, and the wire connected to that trace is an original Apple modification.

>My Lisa is a Lisa 2/10
>
>I've checked the voltages through the widget drive power cable. The
>-12v connection measures -12.5v, the +12v connection reads +12.3v,
>and the +5v connection reads +5.2. I think these are all in range.
>
>Per your request, I've uploaded a short album of pictures
>here: http://applefrikker.imgur.com/. Hopefully this will help in
>diagnosis. The trace on the I/O board I was worried about before is
>photographed, as well as the orange wire I referred to.

-- 
-- 
-----
You received this message because you are a member of the LisaList group.
The group FAQ is at http://lowendmac.com/lists/lisa.html
To post to this group, send email to lisalist_at_email.domain.hidden
To leave this group, send email to lisalist+unsubscribe_at_email.domain.hidden
For more options, visit this group at http://groups.google.com/group/lisalist
--- 
You received this message because you are subscribed to the Google Groups "LisaList" group.
To unsubscribe from this group and stop receiving emails from it, send an email to lisalist+unsubscribe_at_googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.