recently bought an Apple Lisa 2 off of craigslist. The case looks exceptional for its age, and I'm looking forward to fixing it up. However, I have some questions:
1. When I turn on the machine, the light under the screen turns on and the screen is dark for a while, and after a while a grey screen with a pattern of diagonal lines shows up on the screen; looks like there's no video information coming to the CRT. Brightness knob on the back still works. Anyone know what problem this might be?
2. I don't have a keyboard for this Lisa, but I've read that it used a TRS style connector. Is there, to anyone's knowledge, a converter for keyboard signals, either from:
a. RJ10 (Mac 128k) to TRS
b. ADB to TRS
It'd be nice to get a keyboard attached, and this is the only way I can think to do it without shelling out even more money.
Some general information:
Contacts have been cleaned on all boards, memory module 2 suffering semi-major/major corrosion damage on about 4 pins, the power supply pins have a bit of corrosion on them as well. When I power it up, there are no sounds from the speaker at all (no "clicks" or error chimes). 341-0176-H and 341-0175-H are the codes of the ROM chips; those have also been removed and their "legs" cleaned (could problem 1 referred to above be caused by bad roms?). I adjusted the picture controls for the CRT to make it fit the frame of the computer again, but this had no effect on problem 1 listed above.
I've tried switching the memory cards in every possible configuration... No effect.
I've read that capacitor C8 next to the 68000 can initiate an infinite reset loop; I've cut one of the legs on that cap, and apparently pushing reset will start the CPU after the computer has started. No effect.
I've ordered a pair of H roms, cheap, just to have parts around for future projects. Tried to switch the ones I have for these; no effect. These ROMs were guaranteed working.
I've connected the video out cable to a TV; I could tell the TV knew it was plugged in but there was no video information.
When I press the reset button when the screen is on, the horizontal lines "jump up" briefly and then settle back into place.
I can't power off the computer by pressing the power button.
If anyone needs pictures to diagnose, please post with whatever picture you need and I'll be happy to provide it.
Thanks for all of your time, I really want to get this important part of computing history back into working order!
1. When I turn on the machine, the light under the screen turns on and the screen is dark for a while, and after a while a grey screen with a pattern of diagonal lines shows up on the screen; looks like there's no video information coming to the CRT. Brightness knob on the back still works. Anyone know what problem this might be?
2. I don't have a keyboard for this Lisa, but I've read that it used a TRS style connector. Is there, to anyone's knowledge, a converter for keyboard signals, either from:
a. RJ10 (Mac 128k) to TRS
b. ADB to TRS
It'd be nice to get a keyboard attached, and this is the only way I can think to do it without shelling out even more money.
Some general information:
Contacts have been cleaned on all boards, memory module 2 suffering semi-major/major corrosion damage on about 4 pins, the power supply pins have a bit of corrosion on them as well. When I power it up, there are no sounds from the speaker at all (no "clicks" or error chimes). 341-0176-H and 341-0175-H are the codes of the ROM chips; those have also been removed and their "legs" cleaned (could problem 1 referred to above be caused by bad roms?). I adjusted the picture controls for the CRT to make it fit the frame of the computer again, but this had no effect on problem 1 listed above.
I've tried switching the memory cards in every possible configuration... No effect.
I've read that capacitor C8 next to the 68000 can initiate an infinite reset loop; I've cut one of the legs on that cap, and apparently pushing reset will start the CPU after the computer has started. No effect.
I've ordered a pair of H roms, cheap, just to have parts around for future projects. Tried to switch the ones I have for these; no effect. These ROMs were guaranteed working.
I've connected the video out cable to a TV; I could tell the TV knew it was plugged in but there was no video information.
When I press the reset button when the screen is on, the horizontal lines "jump up" briefly and then settle back into place.
I can't power off the computer by pressing the power button.
If anyone needs pictures to diagnose, please post with whatever picture you need and I'll be happy to provide it.
Thanks for all of your time, I really want to get this important part of computing history back into working order!