I documented the MITS Altair 8800a I received in a similar manner to the MITS Altair 8800.
Out of the box, the Altair 8800a looked pretty good. There was some case damage, but the front panel was nearly perfect.
The insides of this machine, much like the 8800, were dirty and rusty, but operable.
The Rev 1 CPU card is in fairly good shape. An Intel 8080A drives the machine.
Like my 8800, this machine has a 2 card disk subsystem. It's a different version then the one in the other machine, which can be seen on these two cards.
This disk controller card is most significantly different from its sibling in the other Altair machine.
The 8800a EPROM card has two EPROMs mounted. One is the general boot loader (tape and paper tape) while the other is the boot loader for the disk drive. I'm not yet sure if there is still data on the EPROMs.
This machine hosted a multi-user system and probably had several terminals attached at one time. There were 2 SIO-2 serial cards installed.
This machine had 56K of RAM installed. 24K static and 32K dynamic. This is the 16K static card.
There are two of these 16K dynamic RAM cards in this Altair. I'm not sure how well Static and Dynamic RAM get along in the same system. I'll find out in time, I'm sure.
Here are the two Altair disk drives. The one without the label (and without a power switch) belongs to this machine.
The original owner of the Altairs in my collection came across some additional documentation after a move. Included were the manuals for the disk drives, the 8800a and almost all of the S-100 cards supplied with the machines!