FS: MITS Altair 8800, repaired/tested/working, unexpanded 2-slot system!

[glitch]

link: https://www.ebay.com/itm/274079460643

Just finished repairing and testing this one. It came to me totally unexpanded: only two S-100 slots, containing the 8080 CPU board and MITS 1K static RAM board! I didn't want to solder in any other slots, since it's pretty uncommon to find them unexpanded, so I wire wrapped a multifunction board with 32K RAM, 2K ROM, and a 6850 ACIA that's set up to be compatible with the MITS 88-2SIO board's first port. So, even with just two slots, you can load and run BASIC!

As with basically every other Altair 8800, the front panel needed to be completely rewired.

 

[Chuck(G)]

That's odd--my 8800 kit came with the connectors for all 4 slots--but then, I ordered mine with the CPU, SIO and two 4K DRAM boards. I don't recall if MITS packaged a connector with each board, which could explain things.

 

[smp]

My kit came with only the CPU (I had to figure out that I had to buy the RAM board later) and a thick 4-slot motherboard with 4 connectors and 8 card guides.
My kit had the same front panel trim strip, and the round-handle switches. No guard screen for the connectors on the rear panel. Otherwise, just the same as shown.
As best as I can recall, I purchased this kit early in 1976.

smp

 

[glitch]

Price dropped to $5000, reasonable offers considered!

 

[falter]

I have been wanting an Altair forever but with exchange rates where they are it's just a bridge too far. I've spent a lot on vintage gear but there's something about $7500CDN in one shot that starts to feel like real money. I'm sort of cruising ebay as every now and again one will pop up for a more modest price. Otherwise I'd have to finance or do layaway.

 

[smp]

I have been wanting an Altair forever but with exchange rates where they are it's just a bridge too far. I've spent a lot on vintage gear but there's something about $7500CDN in one shot that starts to feel like real money. I'm sort of cruising ebay as every now and again one will pop up for a more modest price. Otherwise I'd have to finance or do layaway.

If you're willing to build a bunch of it yourself, an Altair 8800c can be assembled that can use both vintage and vintage-but-made-with-modern-day boards.

See this topic:
http://www.vcfed.org/forum/showthre...00-clone-cost-to-build&highlight=Altair+8800C

I did this, and I love my Altair 8800c. Total cost for me was about US $1000. However, I had the cabinet from my Altair Clone. If you add that in, the total would be about US $1300.

smp

 

[glitch]

Mike's Altair 8800C is indeed a great option for those who don't care if the machine itself is actually old, and just want the experience of hacking on a front panel S-100 system.

 

[glitch]

Sold for $3900 shipped. Figured I'd post the actual price here since eBay seems to be showing the BIN as what things sold for, instead of the actual Best Offer price.

 

[Dwight Elvey]

It is possible that the person that was building it had a one of these All-In-One boards and a floppy controller. One of the most common issues, with both the IMSAI and Altair, was shorted solder joints on the mother boards. Only putting 2 sockets in made sense. Also, he may have wanted to bring it online slowly for the same reason. Getting it working with 2 sockets would be CPU board and RAM board. One could them add one socket at a time, until the desired number of sockets was reached. Checking operation one socket at a time might make sense. There are of course some shorts that may not show up until later if the test was not inclusive enough. Still for most faults, it makes sense.
Knowing you had a short is easier than finding the short. I have techniques for finding shorts that I've described in the past but is does require equipment that not everyone has.
Dwight