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1970s IBM 24-pin ribbon cable connector

stepleton

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Posting to "Minis and Mainframes" because I'm guessing that most 1970s IBM fans hang out here. I'm looking for plug and socket components for a system of 24-pin connectors that IBM used for ribbon-cable interconnect in the 1970s. Here is a diagram of such a connector:

Connector diagram

And here are some screen-captured images of the cable-end connector from YouTube videos of an IBM 5120 repair by Jerry Walker:

ConnectorUnsheathing the contactsUnsheathed


What you find on the end of a power cable is slightly different, but I think the connector itself is compatible. (Don't be fooled by the fact that only one row of holes is visible:

Power connector

The lighting and the video compression algorithm have erased the rear row of holes. I'm pretty sure this connector is mechanically identical to the other connectors shown.)

I don't have a good picture of the connector on the board side, but I think that these are just regularly-spaced metal pins soldered into the PCB. In other words, it's not a separate component.


Either way, I'd like to get my hands on both polarities of this connector --- or to have a good idea of how to make a DIY substitute. After seeing the CuriousMarc 9825T failure, I'll be designing and building a voltage protection device for the DC power supply lines inside my IBM 5100, and I'll need these connectors in order to non-destructively interpose my device between the power supply and the electronics.

Does anyone know how I might be able to get some of this interconnect hardware, or does anyone know where I can find detailed documentation on the connectors?

Apologies for the off-topic post. Then again, depending on your point of view, the 5100 is neither a mini nor a mainframe, or it's both at the same time!
 
Neat solution. BTW, there is always kapton tape if you need to isolate away potential shorts. It might not sit good on your adapter, but it can be applied to the metal restraining bracket.
 
Thanks; I'm awaiting more parts to try it out in the intended application. I mention Kapton tape on the bracket in the writeup under Figure 8, but that's just speculation --- it's good to know this is a likely solution.
 
I guess it's nice to know that impossible to find connectors are a long tradition at IBM. I wish a similar improvisation would be feasible for the plug IBM decided to use on the back of the IBM 5140 Convertible for the expansion bus...
 
Making an extender board for the 5100,5110 computers seems like a possibility using this info.
 
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