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[ried]

I picked up a Lisa 2/5 that was modified and sold by Sun Remarketing. It has the H ROMs and does not have the square pixel screen modification. Interestingly, it has both the 800K floppy drive and the Sun Remarketing 20MB hard drive, a Kalok KL-320. The internal hard drive has a hand-written sticker indicating that LOS 7/7 was installed on it in 1989 

Unfortunately, it retained its original batteries until today when I removed them. As such, the I/O board is likely ruined, and the motherboard has probably sustained significant damage as well. I plan on first trying to repair those, and replacing them if a repair is not feasible.

A couple of questions!

First, does LOS have any issues with the 800K floppy drive? I thought that these originally shipped on Macintosh XLs with MacWorks, but apparently Sun Remarketing shipped them on LOS 7/7 machines that have H ROMs and lack the square pixel mod (like this machine). I suspect that the Sun Remarketing ROM on the I/O board allows LOS to work with the 800K floppy drive, and perhaps it ignores the top side of the floppy disk? Using only the 400K and read/write head on the lower side, like a 400K drive?

Second, if the motherboard is damaged beyond repair, is it possible to replace it with a Lisa 2/10 motherboard and a 2/10 I/O board and retain 800K drive functionality? I realize I would also need a 2/10 cable harness and would subsequently have to replace the hard drive with i.e. an X/ProFile, but I like the idea of having a full 800K drive available to MacWorks. Maybe this is a bridge too far...

Lastly, the I/O board has a bodge wire running from a capacitor at C33 to another point on the board at or near R43. Corrosion from the battery leak has caused this bodge wire to loosen from the board, and I am unsure where it was originally soldered. Anyone know where that loose end should be? EDIT: It attaches to the solder pad between R43 and C45. Interestingly, ALL of my Lisa 2/5 I/O boards have this same bodge wire connection. Never noticed that before.

Thanks in advance.

[blusnowkitty]

First, does LOS have any issues with the 800K floppy drive? I thought that these originally shipped on Macintosh XLs with MacWorks, but apparently Sun Remarketing shipped them on LOS 7/7 machines that have H ROMs and lack the square pixel mod (like this machine). I suspect that the Sun Remarketing ROM on the I/O board allows LOS to work with the 800K floppy drive, and perhaps it ignores the top side of the floppy disk? Using only the 400K and read/write head on the lower side, like a 400K drive?

There is an 800k driver for the Office System out there: https://macintoshgarden.org/apps/lisa-office-system-800k-driver

I'm not sure if you have to have this driver installed or if it'll work as a 400k drive without.

[AlexTheCat123]

I'm not sure if you have to have this driver installed or if it'll work as a 400k drive without.

Without the driver, it will just work like a standard 400K drive.

And I don't see any reason why replacing the motherboard, I/O board, and wiring harness with those from a 2/10 wouldn't work. But, unless you already happen to have those spare parts on you, it might be cheaper to just build your own replica 2/5 motherboard and/or I/O board instead!

[pintoguy]

I have a similar problem with my 2/5 motherboard. I started to repair some of the traces, but so many of them are broken, that I'm starting to think that a replacement board is in order, using original components. I remember seeing some of these bare 2/5 MB's on eBay, but can't find them today. Does anybody know where I could buy one ? Alternatively, has anyone had success with fixing traces with those silver ink pens for trace repair ? How about these via repair rivets ?

[Lisa2]

There is an 800k driver for the Office System out there: https://macintoshgarden.org/apps/lisa-office-system-800k-driver

I'm not sure if you have to have this driver installed or if it'll work as a 400k drive without.

This driver is not needed for using the 800K drive with LOS.   It is kind of neat how it works with LOS, if you have it enables it to use the fully capacity of a DD disk as you would expect, internally it writes to one side of the disk first and then the other side.   Later on it is even possible to read /write data on one of these DD disks on a standard Lisa with only a 400K drive with the limitation that you will only be able to "see" the data on one side of the disk.

If you end up using a 2/10 I/O board will also need to get sun's 800K I/O ROM for the 2/10 also as it is different  than the ROM on the 2/5 board.

[pintoguy]

I have a similar problem with my 2/5 motherboard. I started to repair some of the traces, but so many of them are broken, that I'm starting to think that a replacement board is in order, using original components. I remember seeing some of these bare 2/5 MB's on eBay, but can't find them today. Does anybody know where I could buy one ? Alternatively, has anyone had success with fixing traces with those silver ink pens for trace repair ? How about these via repair rivets ?

OK, never mind. I went ahead and ordered 5 of them on JLCPCB. Thanks @AlextheCat123 for making these boards available to us. I'm always in awe at the kindness of my fellow Lisalist2 members. Unless I screw up big, I will only use one, so I'll make the 4 spare available at cost to other members if they need them. I'll update on this project as I progress.