When repairing DEC PDP-11s there's always the need to see whats happening on the main system bus. On older 11s this is the UNIBUS.
After several try-and-error cycles, I think I now have the perfect signal adapter for UNIBUS ... calling it "UniProbe". In KiCAD 3D rendering it looks like this:
No vapor-ware!
Such an adapter needs to fulfill these criteria:
- must be pluggable into UNIBUS backplanes, and must not break the UNIBUS signal or termination chain.
- should have some lights to visualize bus traffic and error conditions.
- must have some means to connect logic analyzer probes to UNIBUS signals.
- lights and probes must be accessible even if the adapter is completely hidden in the card cage.
- be mechanically robust and compact enough to make not more problems than it helps solving.
My typical setups always violated condition 5:
Now I can show it my mom:
