Macintosh Quadra 800 Restoration

I was recently able to add a Macintosh Quadra 800 computer to my collection.  This computer came from another collection that my friend John and I helped clean out.  I'd been on the lookout for a 68040 based computer that was on the A/UX Compatibility list, but I knew that the Quadra 700 would be out of reach for me price wise due to its popularity.

As I have previously blogged about, I've already restored a Macintosh IIci System that I run A/UX on.  This was a fun project and I learned a ton about classic Mac hardware, but it's not the fastest Apple Unix experience, so I've had an '040 machine on my wish list since that project ended.

My Quadra 800 has had a hard life, there's some light rust on the shielding inside the case, but it's nothing as bad as two of its sister machines which had been stored on the ground in a shed for many years.  But despite the poor storage conditions this machine still boots up and runs.  For some reason the machine had three video cards installed, so with the built in video this machine from 1993 would have been able to have four monitors attached.  The hard drive had died, so I was not sure what the machine had been used for, but a four monitor setup would have been interesting and unusual!

The restore process on this machine was pretty straightforward.  I was able to find the Apple Service Source manual online and used that information to take the machine apart.  While it's not at all easy to take apart compared to the Macintosh II series, it's really not that bad compared to PCs of the time.  After I had the machine all apart I cleaned the case with warm soapy water and dusted the main logic board.  The logic board on this machine doesn't have any Electrolytic caps so I didn't have to recap this machine.  I replaced the Tadiran Clock Battery w/ the same brand, so this computer should be good for another 30 years.  A couple of the drive bay covers were loose so I used Hot Glue to attach them from the inside of the case, it looks really nice on the outside and they drive bay covers are secure.

The floppy drive in this unit needs attention but I had another manual inject drive ready to go so I swapped that in.  I will service this drive at a later time.  This machine came without a hard drive.  I decided to use the ZuluSCSI Hard Drive replacement in this machine as I had one on hand, but also I like the mounting options on ZuluSCSI better than the options for BlueSCSI V2.  I can attach Standoffs and zip tie the ZuluSCSI down on the bottom of the machine with the SD card facing out the back of the computer.  Perhaps if I had a 3D printer this wouldn't be as big of a deal.  But as things are now, this makes it alot easier for me to experiment with alternate OSes, swapping SD cards for MacOS and Apple A/UX.

One other upgrade was to go through my supply of RAM and see if I could find matching pairs of FPM RAM, I was able to find another pair and bring the machine up to a total of 104 MB of RAM.  The memory check at power up takes quite a while about 30 seconds from power up to the chime, but it's a worthwhile compromise to have this machine near its max capacity.

One quirk with this machine is the strange Ethernet connector on the back.  It requires an Apple AAUI Media Adapter so I installed that with this machine and got Internet going with MacOS 7.6...

Getting Apple's Unix A/UX to boot was almost too easy with the Zulu SCSI, as I had a backup of the Disk Image from the BlueSCSI on my Macintosh IIci.  I was able to copy that onto another SD card, install that into this machine and it booted the first time.  There was a warning message from A/UX about the hardware change, but it made those changes automatically and after a single reboot the machine came right up and ran.

Remaining tasks that I have for this build are to configure networking in Unix.  This should enable me to transfer program files or build new tools on this Unix as it is missing alot of the "quality of life" tools that I've gotten used to with modern Linux distributions.