A closer look at the logic circuits. These perform a Modulo 2
addition,(XOR), just like the relay circuits on the German Lorenz
cipher machine. ( 0 + 0 = 0; 0 + 1 = 1; 1 + 0 = 1; 1 + 1 = 0; )
Beneath the logic panel is the master control plate. This was very
difficult to re-create and get working. No circuit diagrams survived.
But Tony Sale based it on a surviving master control circuit for
Super Robinson and eventually it worked.
It provides the pulses within the blank tape join interval to dump
the counts, reset the counters, set the rings to a new start point and
start the rings and counters for the next pass along the cipher tape.