[ih] Arpanet physical connectors

Noel Chiappa jnc at mercury.lcs.mit.edu
Thu Jul 23 20:38:46 PDT 2020

    > From: Steve Crocker

    > The BBN team designed the connector.

As discussed, for the older LH interface, there is no standard connector?

For the later DH interface, I'm fairly sure that they used an 'off the shelf'
mil spec connector, available from Amphenol? (Report 1822 gives the Amp part
number as 48-16R18-31P; the manual for the SRI PDP-11 ARPANET interface
[available here:


if anyone is interested] gives a slightly different one, 48-10R-18-31S. That
might be the female, to the above which is, I am pretty sure male, though.)

The BBN team did design the interlocked bit-serial interface spec, with
the Ready-For-Next-Bit and Theres-Your-Bit synchronization stuff.

    > From: Jack Haverty

    > those particular connectors were readily available through the usual
    > channels --- with a lead time of 60 weeks to delivery! 

So I'm curious - what did you all do than?  :-)


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