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View Full Version : lisa no boot?



harry
September 14th, 2008, 04:11 PM
well I collected the lisa 2, today, brought it home, stripped it out, only to find
the battery pack leaking , but luckily no bad damage to the surrounding components or board, so I unsoldered them and washed the board, every thing
looked it very good condition. the assembly was easy,( they were certainly made with easy maintainence in mind.) when I powered up all seems fine, front
light came on, screen warmed up I can adjust brightness, but that is it ! no self
test, no text, no icons, just thin white horizontal lines, not moving or flickering,
just fixed across the screen, I have no keyboard, only a mouse, but I assume it should do its boot tests? can anyone suggest what to look for, or has anyone had same screen response? .......harry

alker
September 15th, 2008, 03:37 AM
hi, it looks like the I/O board where the batteries were is having difficulties... how did you "wash" the board?!?

if the system check does not come on usually the I/O board is gone... you may ask john from vintagemicros.com - the only supplier of this boards - if he still has a spare board.

harry
September 15th, 2008, 01:50 PM
I have double checked the i/o board and I have found the diode above the batteries coroded thro on one end , there is 5v supply to one side, so I must replace this first.the board I washed with warm water and natural washing soap,
then completely washed with clean water, when dry, I then spray the board with circuit board flux cleaner,then wash this away.this usually brings up boards really well, and now tonight I have gone over it with a strong magnifier, which has shown up this fault, other than that, the whole system looks good as new! any info on what the diode capacities are, would be great! must be a schematic of the i/o board somewhere?? ..... Harry

Druid6900
September 15th, 2008, 08:52 PM
Here's one for the Lisa (1).

http://www.freeinfosociety.com/electronics/schemview.php?id=1416

I don't recall how similar they are, so, it may not be of any use to you.

harry
September 16th, 2008, 02:05 PM
Thanks for the schematic link, unfortunately the diode in question does not seem to be listed on this early board, but hopefully John at vintagemicros, will be able to get me sorted with a diode, so I can look forward to a little progress
shortly! ........ harry