Nexus wiring did change over time, but I'm surprised to see 50R cable in use. Not impossible in point-to-point with line drivers intended for RS423 use, but seems unlikely we would have chosen that.
My recollection is that long-haul hard wired cable was to be IBM Type 2 Token Ring cable (which IIRC had 150R characteristic impedance). I still have a couple of drums of it in my garage... Drop cables had to be something different as it was huge and inflexible.
At the time of the very first Nexus interfaces, the EMC Directive had just been announced and we'd been visited by some EMC consultants - hence the first interfaces were bristling with EMC components (common mode chokes on all the signal lines?) which were subsequently deleted.
I was less hands-on with this stuff than I was with Econet so my memories are more vague.
My recollection is that long-haul hard wired cable was to be IBM Type 2 Token Ring cable (which IIRC had 150R characteristic impedance). I still have a couple of drums of it in my garage... Drop cables had to be something different as it was huge and inflexible.
At the time of the very first Nexus interfaces, the EMC Directive had just been announced and we'd been visited by some EMC consultants - hence the first interfaces were bristling with EMC components (common mode chokes on all the signal lines?) which were subsequently deleted.
I was less hands-on with this stuff than I was with Econet so my memories are more vague.
Statistics: Posted by arg — Sun Jul 06, 2025 11:36 pm