datasheet for the ZN1040E.
TFW8B sells them).
PET diagnostics PCB, which is effectively a breakout board for the microcontroller on board to allow it to drive the PETs address and databus etc. Here I've aligned the 28 pin socket so the display segments are all on one 8 bit port.
The LED modules were, of course, RS branded, 586-526 (discontinued).
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