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Excellent find! That was a very informative read - thanks for posting! :)

Going to have to take a few days of after-hours progress off on this to rapidly install a drainage system for my yard before round two of heavy rain hits the DFW region this coming weekend. Spent yesterday morning digging a trench in my back yard to prevent my shop from flooding, so we're just...

Okay, small update... well, less an update and more just providing some reference images. They're a bit large, but they're a fraction the size of their TIFF parents. These are unfortunately only 400dpi; I have access to another large format scanner that can go up to 12800dpi (lol, each side of...

Mine has them as well, and just like yours they are spliced in manually. Alex's must have been an earlier revision.

Huh - TIL. That's pretty awesome! What model InFocus did you use?

Heh, not an "optional" board, unfortunately - the Lisa backplane just pipes the same TTL video signal that goes to the CRT out to an RCA jack for connection to a TTL-capable display.

Jokes aside, I'm wondering if those were just to prevent wonky power situations from damaging the parallel interface logic... That looks like one of Alex's boards; I'll reach out and see. They may not be necessary, but I don't know that I'd run without them.

On to unfortunately bigger things! Next up is the CPU card and, boy oh boy, is this going to suck. First and foremost, a huge thank you to user jamesdenton over at LisaList for providing me with a busted CPU card, as he's allowed me to depopulate it and scan it for reference for this task. I...

Bit of an update. The preliminary draft of the 512K card is done and ready for review. This is the two layer version; I'll be working on the four-layer soon, but wanted to put the two layer board to paper first. I want to sleep on it and look over it one more time in the morning before pushing...

You know, I saw a post about that in a local (DFW) retro computer group and just figured it was some Apple II thing, based on the color scheme. Guess I should have looked a little closer, lol.

As part of my ongoing efforts to resurrect my Lisa 2, I've stepped back to work on a much broader goal: the reproduction of the Lisa's card stack in full. While the motherboard and I/O board have been reproduced, they are either no longer in production and impossible to find (in the case of the...

Small preview of where things are headed; this is just a rough draft, so don't worry too much about some of the positioning and silkscreen issues. More to come later this week; stay tuned...

The heck? Are you the guy who designed these? If so, kudos! If not, thank you very much for pointing me in their direction! This is fantastic and serves as a good time to update with progress. So, the PSU is sidelined for the moment. It's not dead dead, just "TV" dead (it'll probably be back)...

Geez, dude - more than anything, glad to hear you're doing okay! R29 is functionally useless; I've replaced it with another pot with the same results - no adjustment to output voltage whatsoever. I'm combing through LisaList for info on U3; there's only one left on eBay, so I may go ahead and...

Surely! I'll grab the project list from Mouser in a bit. The card edge connector was off of a Pac-Man arcade PCB filter board I had lying around, but they can be had for about $6 from Mouser as well (22/44 pin EDAC brand).

Okay, the results are in! I assembled a load tester (pics below) and got the following voltages before the fuse blew again: +5v rail: +8v +12v rail: +18v +33v rail: +53v -5v rail: -5v (one success, at least) -12v rail: -18v +5 standby: +5v (5.5, but, eh) The same two caps puff up after a very...

Signs of life... sort of. I recapped the PSU and checked the six main transistors. Mostly satisfied with the results, I checked everything for glaring issues, dropped the PSU back in its cage, and fired everything up... to hear the CRT coming to life and see the power indicator light on the...

Alrighty - PSU images attached!

Yeah, that was my worry - the fuse was just the iceberg for something else inside the PSU. Fortunately, it doesn't blow after being powered on now, though. Thank you for taking a look at your PSU! I'll grab some pictures of mine in a moment after I finish inhaling lunch.

As for the PSU, it makes the familiar chirping when attempting to power on the Lisa (the I/O board is removed for cleaning, but I wanted to verify the machine would even power on first), so I've been going over everything I can think to. Using the thread by @rdmark as a guide, the six main...