My SCRs and resistors arrived from Digikey today, but I haven't built a circuit yet to test it out, mainly because I spent my day as a volunteer examiner for ham radio license tests today.
PICKUP OF 3178 TERMINALS
I spent the day yesterday on a road trip with a friend who had acquired an IBM 2540 Card Reader/Punch, hauling it back to the bay area from Sacramento. While picking up the unit, we both looked around the seller's facility where he had several 4361 and 4331 systems, keypunches, tape drives, terminals and more modems and routers than I though existed on the planet.
I picked up two complete 3178 (green screen) terminals (part of the IBM 3270 family) plus a spare keyboard and spare monitor. Now I have to pick up a controller such as the 3174 to make it usable with my P390 system. Testing (without a controller so very very limited) seemed to show everything working well.