Remember the Altair 8800?

[Analog]

It was an 8080 microcomputer kit from the 70s? I remember it well. I considered building one, but it was expensive at the time, and I went for the RCA VIP 1802 instead.

Here is a link to a guy who is offering a replica kit that is almost identical, down to the traces on the circuit board:

http://www.altairkit.com/index.html

 

[Sceadwian]

The kit was announced 2 years before I was born unfortunatly. Hopefully that doesn't make anyone feel as old as it makes me feel like I missed out on a really good time to be interested in electronics. If you've seen the scope of the projects on a lot of hobbyists websites out there nowdays it's kind of intimidating.

 

[RadioRon]

Ah yes, the Altair 8800. I remember it well. My buddy at Technical College built one from the kits he got from Altair. Then when we both went to first year Engineering school in '77 he found he was playing with it too much and offered to lend it to me for the month before Christmas exams. So guess what I did with most of my study time? Yep, you guessed it. But I did OK on my exams anyway.

At that time he was running the Cuter operating system from Processor Technology as this was a year or two after the 8800 first came out and things had progressed somewhat. This was the same software used in the Sol-20. There was no non-volatile memory in the system so every time I wanted to use it I had to program a boot loader into the machine using the toggle switches, then run the boot loader. I think it was about 50 bytes long. In turn, it would load Cuter from a cassette tape. You had to do this a few times to get it to work as the tape was not reliable. I think there was only about 4K bytes of RAM in the system at that point, which was a lot at that time. I remember that the OS took about 2K bytes of that. I'm pretty sure the BASIC/5 interpreter was very small, but it was a lot of fun to use. Maybe we had 8K bytes in the system, I can't recall. Hard to imagine the OS plus BASIC plus an application program all fitting into 4K.

I can remember trying it out when it was first built it in 1975 (or was it 1974?), but it only had 256 bytes of memory at that time so all we could do with it was toggle in a simple game played with the LEDs on the front panel.

Anyways, back to the story of when I borrowed it. Once you had the OS loaded, you could load a couple of programs including Basic/5 or, my favorite, a game called Targets. I played Targets a lot, and got very very good at it. Ah yes, those were the days alright.

Anyone out there remember targets? The game screen looks like this:
https://www.sol20.org/screens/targ.gif
I was happy to find a version that runs on the PC some years ago.

This computer was a big deal to me because at about the same time the first Star Wars movie came out on a new technology called 70mm film. It was great and it inspired me to build my own X-wing fighter simulator using my own version of the Altair 8800.

After some shopping and planning I ended up building something a little bit different out of S100 kits based around Thinker Toys Z80 processor board and an IMSAI Video card. This was a good combination as it had a ROM'd monitor (a mini-OS) and I didn't need a toggle switch front panel. Once this was combined with an ascii paper tape reader and an ASR-33 teletype and a video monitor I was in business.

A year or two later I upgraded to an 8 inch floppy disk drive that I got from Morrow and managed to get CP/M running after modifying the BIOSs to suit my hardware. Once CP/M was up and running I finally had a real computer and used it for several years mainly as a word processor for my school papers. Too bad I never did get the X-wing fighter simulator running. Its amazing how much work it is programming games!

All this time I stayed in the field of RF electronics professionally so I was getting a lot of training in both fields. My hobby of playing with and then later building a computer stood me well in getting me some really key jobs later on in my career so I think I got an awful lot out of that computer hobby. Funny thing is, I sunk about $5000 from my summer jobs into all the bits and pieces for my S100 machine and in the end sold it for $20 at a garage sale, and happy to get that too. It was, nonetheless, a good investment.

Those of you who are active in your electronics hobby, building stuff and trying to figure it all out, keep it up, it will pay off.