So the PDP8/e used the KC8-EA programmers console which has incandescent indicator lamps and the PDP8/f used the KC8-FL programmers console which has LED indicator lamps.
Why? The maintenance manual says that LEDs are more reliable. The operation is as far as I know the same. The LED version doesn't need the +8VDC supply, but that seems an advantage for it. I remember reading that the EAE had some revision dependencies with the console, so were there bus timing problems with the LED console that limited it to short buses? Maybe this changed over time, but it overlapped long enough for them to have both described in the maintenance manual and specific to the application. Another console question... Has anyone ever seen a PDP8/i style console for the PDP8/e? Looking at the way the PDP8/e console functions, it should be possible to time multiplex all the register to the data bus so they are all visible at once when the machine is halted. -chuck