Starting the New Year Right - Macintosh 512K - Part 1

Happy New Year, everyone!  I'm starting the new year right with an exciting addition to the collection, the Macintosh 512K, released in late 1984.

I'm really enjoying this system, and started out by doing a bit of "Computer Archeology" on this system.  One of my favorite things about Retro Computing is trying to figure out the back story on the systems.  For a couple of my systems I know they were purchased new by a family and held by them till I got them, but most of the systems have a certain amount of mystery associated with them.  This system has a couple of service stickers on it, and the previous owner (a fellow collector who has been doing this much longer than me) told me that he had swapped the Logic Board to get this machine back up and running again.  So I actually have more background on this computer than I do on most of the computers in my collection.

This system has a case from an Original Macintosh with a Serial Number that indicates that it was made in the 14th week of 1984, which I believe makes this case one of the first one hundred thousand units sold.  However, like so many of these units it was upgraded too a 512K board early in its life.  There's a sticker inside the chassis that indicates it was serviced at Heathkit Electronic Center on 6/15/1987 and this sticker has 512K printed on it, which seems to indicate that the upgrade had be carried out on or before that date.  The floppy drive and Power Supply board also have 1986 dates on them, so they may have been swapped at that time as well.

There is another sticker on the bottom of the chassis for a repair carried out at Midwest Visual Equipment in New Berlin, WI on 12/30/92.  This demonstrates that the machine was still being used 8 years after it was new, and used enough that it was worthwhile to have it serviced again.  I have no idea when the computer would have stopped being used, but within 2 years after that service the Power Macs were starting to be introduced.  That would have been quite the performance gap at that point in time.

As I've already mentioned, the main logic board was replaced more recently than any of the other repairs.  I don't know the date of the board itself, but the latest date code on the chips is from the later half of 1984, so this may have been a board from an earlier 512K example.

This computer has an 800K floppy upgrade.   I didn't think I'd be able to use that drive capacity since the 512K has the smaller ROMs (There's no code on the ROMs to run a double sided drive), but I've just learned that if you use System 3.2 with HD20 hard drive support, the ROMs get patched to support double sided drives both internally and externally.

All in all, I couldn't be more pleased with this addition to the collection.  I've always wanted one of these early Macs.  This is a good, solid machine in great repair that I don't have to feel bad about using since it's not a museum piece, which is perfect, since I do intend to use this machine.

I had quite an interesting challenge getting a workflow setup for disk imaging to create 400K disks for this machine, stay tuned, I'll go into that in Part 2 of this series.

What was your first Macintosh?  Let me know in the comments below if you have stories about these early Macs.