DEC bus transceivers

Guy Sotomayor Jr ggs at
Tue Oct 25 15:24:48 CDT 2016

> On Oct 25, 2016, at 12:40 PM, allison <ajp166 at> wrote:
>> Also, I think in a previous email you mentioned that the UNIBUS is 240ohm.  It’s not.
>> It’s 120ohm.
> My book says no. Qbus is for sure 120.

Section 5.2.5 of the PDP-11 UNIBUS spec:
A Unibus segment must always have a Unibus terminator at each end of its
120-ohm transmission path.

So, I don’t know how you get a value of anything other than 120-ohms given that

TTFN - Guy

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