DEC bus transceivers

Christian Corti cc at
Wed Oct 26 04:49:19 CDT 2016

On Tue, 25 Oct 2016, Guy Sotomayor Jr wrote:
> OK, re-reading the first part of section 5.2.5, it?s pretty clear that the Unibus is 120-ohm:
> A bus terminator is defined as a Unibus element or part of an element containing
> a resistive network which connects to the end of a Unibus segment and matches
> the 120-ohm characteristic impedance of the Unibus transmission path.

Or to cite another source: PDP11 Bus Handbook page 76 says
"A bus segment consists of a terminator, a 120-ohm transmission path 
(cable) with options having drivers and receivers, and another terminator 
(in that order)."


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