> On Oct 25, 2016, at 12:40 PM, allison <ajp...@verizon.net> 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. > 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.
Given that it’s hard to see that the impedance of the Unibus is anything but 120-ohms. TTFN - Guy
