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Building and Altair 8800 from Scratch in 2018

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deramp5113

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I finally designed and built the new front panel board for the Altair 8800 I’ve discussed in the past. This adds to the list of replica and drop-in equivalent boards people are making for the Altair. Now a fully functional Altair 8800 can be built from scratch using all new equipment and boards.

Here’s my take on the project: https://www.youtube.com/watch?v=Q5LjkL5b4n8

Mike
 
Really cool, Mike. I can tell you that debugging front panels on the originals was 50% resoldering the wires one broke moving it around. The wires were all solid hookup wire. Most people nick the wire at the end of the insulation when stripping. This makes about 3 bends before breaking. Always have some tape handy to cover the AC wires as well.
Erik Klein had one that was said to have been running at one time but that was unlikely. I found several shorted leads on the mother boards where those wires were soldered.
Dwight
 
deramp5113 said:
Here’s my take on the project: https://www.youtube.com/watch?v=Q5LjkL5b4n8
Click to expand...

Excellent video, Mike! As you know, I already have one of your clones, but I am wanting to get one of those replicas that you're showing off, too. Very cool! I don't see that you're offering the complete system on your web site, yet. Do you intend to offer it? What would your target price be?

smp
 
smp said:
I don't see that you're offering the complete system on your web site, yet. Do you intend to offer it? What would your target price be?
Click to expand...

I don't plan on making a kit of the Altair 8800c I demonstrated. Based on input I’ve received over the last year, each person's ideal system would be a bit different, so a single version of the kit wouldn't be quite what everyone wanted anyway. I'll update the deramp.com website soon with information about where to buy the boards and equipment shown in the video.

Regarding the boards in the video: The 8800 CPU replica is a bare board (not a kit). Likewise, I plan on selling the front panel board set as bare boards as well. The FDC+ and 88-2SIOJP are available assembled. Finally, new mother boards you find will typically be bare boards.

Mike
 
Very nice Mike - looking forward to more information about this!
 
Definitely thinking about doing something like this, although I think the Clone as it is with the emulation is really cool.

I wonder if it'd be possible to get the actual Optima case produced again like Grant Stockly did. Or does he have some sort of rights over it?
 
Optima was bought by Elma, who also purchased Stantron, and now has an Optima-Stantron division. Grant paid them a good chunk of cash to retool for the original Altair case back in 2007 or so. When I contacted Elma in late 2012 about doing the same thing in order to build the Altair cabinet for me (for the Altair Clone), this is when I learned this information. Because Grant paid for the retooling, they said I’d have to purchase the cases through Grant. Unfortunately, the case alone was going to cost as much as my target sales price for the fully assembled Altair Clone, so I ended up designing and having my own custom case fabricated.

Even if Grant were to order more Optima cases today, my guess is that there would be another retooling charge since it’s been ten years since the last order, and costs have gone up substantially over the last decade, so I can imagine the cases would be $700$-800 a piece now.

Mike
 
deramp5113 said:
Here’s my take on the project: https://www.youtube.com/watch?v=Q5LjkL5b4n8
Click to expand...

I enjoyed the video and appreciated the cutaways to the original machine to add context.
The Molex connectors on the top of each board look like those used in the Exidy Sorcerer computer and Exidy arcade games.
I'm not sure Molex make that exact part number anymore. Can you provide a link to the series that you've used?
 
Great to see this completed! Been trying to keep quiet about it :p

I'm working with Gary on kitting up the IMSAI and Altair CPU cards, we've just both been busy with other things to get it really moving! Perhaps we can all work together to provide a base "Altair 8800C Starter Kit" or something?
 
So I'm pretty excited by this. I have a couple of questions for those of you with the knowledge!

#1 is that I'd like a Z80 CPU board instead of an 8080 - one important thing is running Turbo Pascal and that requires the Z80.

#2 is that I would probably go with the 88-2SIOJP that Mike mentions which gives serial I/O and EEPROM capability.

#3 I would need a SRAM board for 64K - is anyone selling kits for these?

#4 Are there any S100 boards that offer a virtual floppy interface? Meaning some sort of thing where you can mount virtual floppies on a SDCARD or something. Maybe this could be a project for me to look at if there isn't anything like it.
 
alank2 said:
So I'm pretty excited by this. I have a couple of questions for those of you with the knowledge!

#1 is that I'd like a Z80 CPU board instead of an 8080 - one important thing is running Turbo Pascal and that requires the Z80.

#2 is that I would probably go with the 88-2SIOJP that Mike mentions which gives serial I/O and EEPROM capability.

#3 I would need a SRAM board for 64K - is anyone selling kits for these?

#4 Are there any S100 boards that offer a virtual floppy interface? Meaning some sort of thing where you can mount virtual floppies on a SDCARD or something. Maybe this could be a project for me to look at if there isn't anything like it.
Click to expand...

#3: I thought that Mike said that there's 64K RAM on that SIO board, too?

#4: Check out the JAIR-8080. It's a complete system on one board, and any of the individual parts (RAM, SIO, CPU, SD) can be enabled or disabled to allow for other boards to be used.

http://www.s100computers.com/My System Pages/8080 CPU Board/8080 CPU Board.htm

http://www.s100computers.com/My System Pages/8080 CPU Board/8080 CPU Board Rev1.htm

Josh Bensadon, the designer, can be reached at: jbensadon@hotmail.com, and also on the S-100 Computers Google Group: https://groups.google.com/forum/#!forum/s100computers

Good luck!

smp
 
Thanks smp - that does have it all except that it is 8080 and I'm looking for the Z80 instead.
 
alank2 said:
Thanks smp - that does have it all except that it is 8080 and I'm looking for the Z80 instead.
Click to expand...

Not a problem! Just disable the JAIR CPU, use the JAIR for SIO, RAM, EPROM, and SD card disk system, and plug in an S-100 Z-80 CPU board of your choice. 8-)

smp
 
There are lots of vintage Z80 boards that will work. I'll probably be doing a reproduction of the TDL ZPU (afaik the first S-100 Z80 board) in the near future. You can also go with one of John Monahan's/S100computers.com boards.
 
If you’re wanting to run a Z-80 CPU and Turbo PASCAL in a CP/M environment, then you don’t really need an Altair specific solution. You’ll have a larger number of options putting together a generic S-100 system with the wide variety of new and/or vintage boards available.

Mike
 
deramp5113 said:
Optima was bought by Elma, who also purchased Stantron, and now has an Optima-Stantron division. Grant paid them a good chunk of cash to retool for the original Altair case back in 2007 or so. When I contacted Elma in late 2012 about doing the same thing in order to build the Altair cabinet for me (for the Altair Clone), this is when I learned this information. Because Grant paid for the retooling, they said I’d have to purchase the cases through Grant. Unfortunately, the case alone was going to cost as much as my target sales price for the fully assembled Altair Clone, so I ended up designing and having my own custom case fabricated.

Even if Grant were to order more Optima cases today, my guess is that there would be another retooling charge since it’s been ten years since the last order, and costs have gone up substantially over the last decade, so I can imagine the cases would be $700$-800 a piece now.

Mike
Click to expand...

I've also contacted Optima-Stantron a few years ago. Same story, Grant is the owner of the tools.
It was impossible to get any reply from Grant. I was wondering if Grant could give a licence
to others to make these cases. But I just was getting nowhere...

I would be happy to pay a good price for a Optima-Stantron case...
 
glitch said:
I'm working with Gary on kitting up the IMSAI and Altair CPU cards, we've just both been busy with other things to get it really moving! Perhaps we can all work together to provide a base "Altair 8800C Starter Kit" or something?
Click to expand...

Glitch - do you (or anybody else, for that matter) have a BOM for Gary's Altair 8800 CPU board with "modern parts"? Of special interest are a replacement transistor for the "CS 4410", the Molex connector, and the Zener diodes - will any 12V and 5.1V Zener do?

<*> Jim
 
Hi Mike,

deramp5113 said:
If you’re wanting to run a Z-80 CPU and Turbo PASCAL in a CP/M environment, then you don’t really need an Altair specific solution. You’ll have a larger number of options putting together a generic S-100 system with the wide variety of new and/or vintage boards available.
Click to expand...

I want it all! :)

I have always loved your clone and while I know it focuses on 8080 and Altair compatibility, my first programming language was Turbo Pascal on IBM PC, so Turbo Pascal on CP/M holds special interest to me. So does the control panel and all the awesome Altair stuff you demo in your videos.

Perhaps I'll have to build both 8080 and Z80 S100 boards to play with both unless someone has a dual board (not likely I'm guessing!)

Thanks,

Alan
 
11/19/18

Hello Jim, if you need an assembly manual for the Altair board, Dave's Old Computer's Website has one for download. As to the parts you are looking for...

Q1 CS4410 (610-2N4410) Mouser
D1 12V Zener (833-1N5349B-TP) Mouser
D2 5.1V Zener (78-ZPY5V1-TAP) Mouser
Molex Socket (538-09-50-7081) Mouser
Molex Pins/Connectors (538-08-50-0134) Mouser

Molex Header-SQUARE Pin (538-26-60-2081) Mouser
Molex Header-ROUND Pin (538-26-20-2081) Mouser

Molex Header-SQUARE Pin (WM22786-ND) Digikey
Molex Header-ROUND Pin (WM13464-ND) Digikey

I don't know which pin type would be better (round/square)...

*Note: Mouser has many incorrect Images for parts they sell
read the descriptions or look at Data Sheets

> Charles
 
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