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simkiss
November 17th, 2015, 07:45 AM
I am the winning bidder at $1,654 + shipping.

Here's hoping that it is what it appears to be and that it's not an empty metal box.

http://www.shopgoodwill.com/viewItem.asp?ItemID=25617461

Nervously awaiting delivery...

smp
November 17th, 2015, 08:10 AM
Wow! It sure looks great on the outside.

Here's hoping that you find a treasure trove inside when you get it.

Congratulations on your excellent acquisition!

smp

pski
November 17th, 2015, 08:36 AM
Someone donated an Altair? I didn't think we'd see that in 2015!

taborj
November 17th, 2015, 09:55 AM
Someone donated an Altair? I didn't think we'd see that in 2015!

There was an IMSAI up there at the same time, too. I'll try and find the URL.

Edit: Found it: http://www.shopgoodwill.com/viewitem.asp?itemid=25617369

deramp5113
November 17th, 2015, 10:01 AM
Based on the front panel and the sharp inside corners on the DB-25 cutouts, this is a very early unit. Keep us posted!

Mike

leiy
November 17th, 2015, 02:05 PM
Wow! Based on all characteristics, it is a genuine 14th Altair 8800 for sure! Wonderful find, Congratulations!

Keep us posted! Thank you for sharing!

I have add the link for Altair 8800 rev.0 survivors list! http://www.vintage-computer.net/?p=144

leiy
November 17th, 2015, 02:14 PM
It has a 88-ACR board inside for sure, base on that I can do some guess, at least 3-4 boards inside.

An Altair CPU board

8K SRAM board installed or one-two 4K SRAM boards plus 1K board.

88-SIO A board installed.

TJ_Mossman
November 20th, 2015, 01:53 PM
Based on the front panel and the sharp inside corners on the DB-25 cutouts, this is a very early unit. Keep us posted!

Mike

How does the front panel differ from later units, and how much later? I didn't think there were any changes before the 8800a?

billdeg
November 20th, 2015, 05:38 PM
Wow! Based on all characteristics, it is a genuine 14th Altair 8800 for sure! Wonderful find, Congratulations!

Keep us posted! Thank you for sharing!

I have add the link for Altair 8800 rev.0 survivors list! http://www.vintage-computer.net/?p=144

Not sure who is running this page, but s/n 43 is not Bruce Damer's, See:
http://vintagecomputer.net/MITS/8800/sn220043K/altair_8800_front.jpg

I also own 00744K too.
http://vintagecomputer.net/MITS/8800/sn220744K/

leiy
November 20th, 2015, 06:30 PM
Not sure who is running this page, but s/n 43 is not Bruce Damer's, See:
http://vintagecomputer.net/MITS/8800/sn220043K/altair_8800_front.jpg

I also own 00744K too.
http://vintagecomputer.net/MITS/8800/sn220744K/

Thanks for provide the information, I will modify the source accordingly.

Could you tell me the 220744K use C8080 or C8080A? The card holder is blue or yellow?

Thank you.

billdeg
November 20th, 2015, 06:39 PM
I have not used in years, sorry I have no good pictures or answers to your questions.

simkiss
November 29th, 2015, 04:05 PM
She has arrived, and she is what I hoped. Clean. Zero rust. Hardly any dust whatsoever. She is GORGEOUS. She had 3 cards:

1). the CPU board (with an 8080 not an 8080A!!!)
2). the 88-SK4 (dynamic RAM) board, though from 1976
3). and the PIO (also called the 88-PIO) board

I will post 5 photos in each of the next 4 replies, should you care to look.

simkiss
November 29th, 2015, 04:08 PM
2805928060280612806228063

simkiss
November 29th, 2015, 04:12 PM
2806428065280662806728068

simkiss
November 29th, 2015, 04:13 PM
2806928070280712807228073

simkiss
November 29th, 2015, 04:14 PM
2807428075280762807728078

Marty
November 29th, 2015, 07:38 PM
Hi All;

Simkiss, Just in case You do Not know the 4K or any Dynamic Memory Board were notorious for being "not able to Remember"..
I had a (I think) 16K in my Origional 8800b, and it would pass Mits Memory Diagnostic..
But couldn't Remember worth a Hoot..
I would try and Load up Basic from my Meca Intelligent Cassette Tape and it wouldn't work.. I would send it back to the Factory, and they would say it was fine..
I finally gave up.. I found out Years Later, that the Dynamic Boards didn't work, and it was not my Tape System..

THANK YOU Marty

tkc8800
November 29th, 2015, 07:42 PM
That's a really great machine, the condition is very impressive for such an early model. What's the possibility of getting a parallel terminal? I know they were used back in the day but are they available these days? I was in the same boat with my Altair, it had an 88-PIO for terminal but I could never find a terminal that could use parallel comms.

simkiss
November 29th, 2015, 07:52 PM
Thanks, Marty. I am aware that the DRAMs were a huge problem from reading the excellent s100computers.com site.

However, I am a little puzzled as to what SRAM boards will work with the earliest model Altair, as the S-100 standard evolved a bit in the mid to late 70s.

I was looking at the Compupro RAM 17 64K board, which is IEEE 696 compatible, but I don't think my 8800 is IEEE 696 compatible...

Any thoughts as to which 64K DRAM boards might work?

simkiss
November 29th, 2015, 07:55 PM
That's a really great machine, the condition is very impressive for such an early model. What's the possibility of getting a parallel terminal? I know they were used back in the day but are they available these days? I was in the same boat with my Altair, it had an 88-PIO for terminal but I could never find a terminal that could use parallel comms.

Slim to none. Like you, I'll go with a MITS 88-2SIO or the Solid State Music IO4. :cool:

leiy
November 29th, 2015, 08:41 PM
Awesome! Definitely a very early Altair 8800, the C8080 K9897 was produced in 1974 late November!

And the PIO is definitely early one, I also have one installed on my SN221876K.

The RAM board maybe produced in 1976, I think the original owner had upgraded 1K static RAM to 4K DRAM in 1976. The board can reliable to load 4K basic without any glitch! You can give it a try!

Here is one of my 4K DRAM board for reference.
http://www.vintage-computer.net/wp-content/uploads/2015/03/Altair_8800_sn221148A_002.jpg

Marty
November 30th, 2015, 09:03 AM
Hi All;

"" I was looking at the Compupro RAM 17 64K board, which is IEEE 696 compatible, but I don't think my 8800 is IEEE 696 compatible... ""

I don't know about Compupro RAM 17 64K board, But I have a Compupro RAM 16 64K board, that I have not been able to make it work..
One of the things that needs to be done is Drill out or Cut pin 20 and pin 70 on any IEEE 696 Board, as pin 20 and pin 70 are used for Write Protect and Un-Protect on the Altairs..
I do have a 64K Static Board that Does work, but I am not able to get to it.. But, it is a Rare Brand..
Compupro RAM 14 16K board Does work, along with Seals 8K Board.. These I have and have tried..

"" Any thoughts as to which 64K DRAM boards might work? "" None that I have tried.. I prefer Static Memory Boards..

THANK YOU Marty

deramp5113
November 30th, 2015, 11:21 AM
The RAM-17 64K board is a good board for use with the Altair. You can easily insert 2K holes anywhere in the address space (four 2K holes in the E000-FFFF range with DIP switches, or 2K holes anywhere by lifting the appropriate pin out of the socket on the 74LS138 decoders used to select the RAM chips).

You can also swap a 2716 or 2732 into any RAM socket(s) as needed for PROM in the system. A 2732 works in a 2716 socket - just program the same 2K of code into the top and bottom half of the 2732 and you don't have to worry about what the 2732 sees on A11. 2732's are readily available at 200ns and 250ns so you don't have to worry about wait states.

For the Altair, configure the board for "Global Mode" (not "Extended Address Mode"). Also use the DIP switches to select "Front Panel" operation (front panel deposits work) and turn off "Phantom."

Marty's point about pins 20 and 70 applies to this board. This RAM 17 ties these pins to ground on the board. As long as you don't plan on toggling the PROTECT/UNPROTECT switch on a regular basis, you really don't have to modify anything. Just keep in mind that when you do flip this switch, the output of the bus driver for these signals is tied directly to ground whilst trying to assert a one. Won't hurt anything for a second or two, but it's not an ideal condition (even though this is essentially how the MITS Turnkey board does its version of "Phantom" to force an auto-jump on power up).

Mike