68kMLA Classic Interface

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Is it a Lisa????? Is it a Macintosh????
Posted by: Gorgonops on 2015-04-15 12:10:26 I'd need to see what it's connected to on at least the Mac side of the house to venture more than a speculative guess but my first thought is that the 7474 flip-flop IC is being used to convert the Mac's direct horizontal drive output into a standard horizontal sync signal. Buried somewhere on these forums (in more than one place, I'm sure) is a link to a page that explains how the Mac's analog board circuitry has a number of shortcuts on it compared to a "complete" stand-alone monitor; if the Lisa's monitor is more "feature complete" you'd need something that does that. (Search for posts about DIY "Hackintoshes" in the old meaning of Hackintosh (or "HackMac") vs the current meaning of the word.)
Posted by: olePigeon on 2015-04-15 13:32:47 I was thinking that maybe it could be a Mac 128k prototype, except that the motherboard is a production board.
Posted by: mactjaap on 2015-04-17 14:12:50 I connected the FloppyEmu to it to experiment. Works fine. I post a picture of it. First time it is on at my home!
Posted by: snuci on 2015-04-17 14:40:42 You've got an HD20 hooked up and it works? That's fantastic! If you could get a Lisa keyboard shell and fudge a Mac keyboard into it, nobody would ever now the difference 🙂
Posted by: Macdrone on 2015-04-17 15:54:53 I think the Lisa keyboard would work as is? Won't it?
Posted by: unity on 2015-04-17 16:02:59 From what I can see in the pics, the Mac keyboard is interfaced on the back of the machine. Like the mouse, it may be a semi-perminant setup. But I have not seen clear pics of the back, but it does not look like the stock LISA keyboard interface is used.
Posted by: snuci on 2015-04-17 16:27:44 I am assuming the Mac keyboard interface works but it would be cool to put a Mac keyboard into a Lisa shell so it would look totally like a Lisa.
Posted by: likanen on 2020-05-22 23:14:39 Sorry to revive this 5 years later but I obtained a similar 128K board with a stack of ram. The lot also included empty Lisa case with non-standard PSU in which the board had been. The seller had modified the board and Lisa by himself (afaik) and he used to work at it department of a local university. I haven’t tried it out but if there are some questions you’d like to ask, I can reach out to him.
Posted by: likanen on 2020-05-23 01:08:17 The board is 512K but here is the photo.
Posted by: ScutBoy on 2020-05-23 06:49:24 More pics of the whole setup, please! 🙂
Posted by: likanen on 2020-05-23 08:36:56 I will. There are 4 other compact macs and various analog and logic boards so I’ll try to sort them out first. That stacked memory logic board just stroke as was it couldn’t fit a compact case so asked the guy how he had been running it.
Posted by: MOS8_030 on 2020-05-23 09:26:58 The board is 512K but here is the photo. View attachment 34027 Wow, that is incredible. The crazy lengths people went to back in the day!
Posted by: Bolle on 2020-05-23 09:31:22 Would this even fit into a Macintosh shell? It would at least need bending the frame as the board wouldn’t be able to slide in with those RAM towers.
Posted by: Fizzbinn on 2020-05-23 09:31:56 Wow, that is incredible. The crazy lengths people went to back in the day! And continue to go to today!
Posted by: likanen on 2020-05-23 09:36:21 Would this even fit into a Macintosh shell? It would at least need bending the frame as the board wouldn’t be able to slide in with those RAM towers. He used Lisa shell for it.
Posted by: likanen on 2020-05-24 07:04:34 Please find attached some more pictures. The power supply is with AT connector and has been attached to the Lisa monitor power in. Then Lisa’s video / logic board connector is sliced and a regular Mac compact connector has been connected to it. I know nothing about Lisa connectors so my assumptions might be totally wrong. That scsi cable is interesting. There is no scsi in 512K so it might be this has been used as test bed for fixing compact logic boards. Does someone know what is that stick with three wires?
Posted by: bibilit on 2020-05-24 07:54:51 Potentiometer... probably the brightness knob.
Posted by: Trash80toHP_Mini on 2020-05-25 23:30:55 Woo, that's some pile of piggybacked RAM! 😱 One wonders if the standard A/B could run such a pile of ICs?
Posted by: ScutBoy on 2020-05-26 11:42:11 Yeah - it's very interesting, but the whole thing kinda gives me the shakes 🙂
Posted by: rplacd on 2020-05-26 14:19:20 Absolutely ingenious. I want to meet the person who did this one-of-a-type thing and ask him about and how and why he did all this!
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