Roger Holmes wrote: Unplug all cables from the back. Unlock the back panel by twisting the two screw locks, and pull it down. Next find the two thumb indentations under the Lisa display in the front, push up and remove the front panel. Next remove the top of the case. You'll find the analog card right behind the CRT. It's accessible from the top. You can crush a small bit of cardboard - a small crumpled slice of one of those fall out subscription cards from magazines will work nicely. Reconnect the power & mouse. In the front, there's a small power cut off switch around where the thumb indentation on the front of the case is, jam the bit cardboard in there. There's another one in the back near where one of the thumb screw locks is. Doing so will allow you to turn the Lisa on with the case off and adjust the pots on the analog board. If you've had the screen modification kit (ROM version will show as 3A/88 or 3A/A8), you may have a transformer between the analog board and the CRT. Perhaps this is related to the issue. Problems could be anywhere from the VS ROM on the I/O board, or the signals from the I/O board going out through the motherboard to the analogboard, and also in the power supply. Before you do much else, I'd disconnect the I/O board, and motherboard and clean out the contacts. Ditto for the power supply. Usual anti-static precautions apply to the card cage/motherboard. After you do that, and whatever you've used to clean the contacts is dry and clean, play with the pots on the analog board (I've had good luck with DeOxit, other stuff works too, as does a rubber eraser - but caution there as these can cause static buildup and might scrape the contacts off if they're worn.) The pots on the analog board are usually glued down so note their position before touching them, and be careful not to crack them, or you'll have yet another part to replace. :-) wiggling them around with a screw driver gently is best - if you can find a plastic tipped one, so much the better, or if not shave down a plastic knife into the shape of a flathead screwdriver so you don't electrocute yourself, or short something out by accident. (I've personally used metal ones and have been careful, so YMMV.) If it's not a 2/10 (if it has an external parallel port on the motherboard) make sure it no longer has the AA NiCad batteries, if it does and they've leaked, they could have damaged the I/O board. Usual warnings about electrocution and causing damage to the Lisa through shorts apply, but you sound like you know what you're doing so I'll spare the usual broiler plate babble about the dangers of touching the wrong items while the machine is powered on and frying yourself, etc. :) Have fun.