General Category > LisaList2
Edge Connector for the IO Board
blusnowkitty:
Whack an old CRT TV/monitor with composite in on the Video Out port, or hook up a scope to the port and see if you have any signal at all - the video port is the same signal that gets fed into the Lisa's internal analog board. Video output is also on Pin 115 of the CPU board.
http://bitsavers.org/pdf/apple/lisa/hardware/lisa-motherboard-enhanced.pdf
https://lisa.sunder.net/cgi-bin/bookview2.cgi?zoom=0?image=0?book=6
pintoguy:
Thanks @blusnowkitty. I had read these posts, and this was going to be my next move.
pintoguy:
mmm, I spoke too soon. The problem seems more complicated than I thought.
1) I checked the composite video signal, and it looks OK, and similar to what I get on a working Lisa (see pic)
2) I swapped the PS with my working Lisa, with same results
3) I swapped the Video board with my working Lisa, with same results
4) The CRT glows red
I was thinking of swapping the whole card cage with my working Lisa 2/10, but this one is a 2/5 with the parallel port. And the 2/10 cage doesn't seem to fit very well. Would they be compatible ? Should I force the 2/10 cage in ?
blusnowkitty:
Have you tried twiddling the knobs on the affected Lisa's analog board? I know when I was trying to get my 2/5 up and running on its original battery damaged I/O board, the video signal was so overdriven the screen was mostly white with black smears here and there.
You could also have a broken component on your analog board. Mine apparently had been used so much that a plastic insulating tube on one of the coils broke apart. Fortunately there wasn't any electrical damage.
patrick:
--- Quote from: pintoguy on April 25, 2022, 12:34:02 pm ---I was thinking of swapping the whole card cage with my working Lisa 2/10, but this one is a 2/5 with the parallel port. And the 2/10 cage doesn't seem to fit very well. Would they be compatible ?
--- End quote ---
This will work as long as you do not connect any floppy or hard drives. The power harness is almost the same for the 2/5 and 2/10, but the drive harness is different.
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