RE: [N8VEM-S100:799] S-100 Backplane Connectors

["John Monahan" <mon...@vitasoft.org>]

Definitely the connector spacing’s are the same for all cards. They are exactly as defined in the IEEE-696 specs.

 

http://s100computers.com/General%20Images/IEEE_696_1983.pdf

 

Possibly the pins into the motherboard may be different, I so I did not know that however. Maybe the width between the front and back rows of motherboard pins are slightly different.  I have an old Altair here and could try and dig it out but would rather not if somebody knows the answer.

 

In any event the connectors described here

http://s100computers.com/My%20System%20Pages/Extender%20Board/Extender%20Board.htm

 

fit the IMASI, Godbout and N8VEM motherboards.

 

John

 

 

From:  John Monahan Ph.D

e-mail: mon...@vitasoft.org

Text:    mon...@txt.att.net

 

From: n8vem...@googlegroups.com [mailto:n8vem...@googlegroups.com] On Behalf Of Robert
Sent: Monday, April 09, 2012 5:13 PM
To: n8vem...@googlegroups.com
Subject: Re: [N8VEM-S100:799] S-100 Backplane Connectors

 

Hello John, (and Brian)

Would it be possible to elaborate a bit? How many different "S-100" connector specs are there?

Also, are you saying that IMSAI connectors are _different_ from Altair connectors, or are you saying that they are both the same as each other, but different from other manufacturers?

I just checked some of my old S-100 boards and they all appear to fit the same connectors. True, the width and depth of each individual edge contactor (on the board itself) does vary minutely, but all the connectors appear to be .125" center-to-center and all the old cards match very closely to our new S-100 boards (cards).

One of the cards was an original IMSAI board, and it matched-up with our new boards quite nicely (meaning that it they should fit in the same connectors). I've seen Altair boards, and I thought that they were interchangable with IMSAI boards.

I found an old 1980 Industrial Micro Systems S-100 backplane, and its pins are spaced (pitch) 1/8th inch (.125") from each other (in a row), and each row of 50 pins is spaced 1/4" (.250") apart from each other. This backplane has 12 slots, which are each spaced 3/4" (.750") center-to-center from each other.

IIRC, the Altair connector spacing was much wider in between edge connectors (center-to-center), but the edge connectors themselves were the same as above.

If anyone has any additional info, it might be helpful.

Thank you,

Robert Greenstreet

 

 

-----Original Message-----
From: John Crane
Sent: Apr 9, 2012 9:29 AM
To: n8vem...@googlegroups.com
Subject: Re: [N8VEM-S100:798] S-100 Backplane Connectors

Depends in your motherboard.  IMSAI and Altair motherboards required DIFFERENT S-100 Connectors.

-John

--- On Thu, 4/5/12, Brian Marstella <br...@marstella.net> wrote:

From: Brian Marstella <br...@marstella.net>
Subject: [N8VEM-S100:799] S-100 Backplane Connectors
To: n8vem...@googlegroups.com
Date: Thursday, April 5, 2012, 6:32 PM

Good afternoon,

I was wondering if anyone might clarify the correct pitch and spacing for the S-100 backplane connectors? I'm finding various references which have improper info. I think the connectors should be the .125" (3.18 mm) pitch and .250" spacing but I'd like to confirm that prior to spending $40+.

Regards,

Brian.