This view is of the unit after it had been refurbished and modified for our Bombe application. Peter Porter kindly carried out this work.
Here the Unit is bolted into the frame but shown before the covers were fitted.
Normally this unit would be fitted with differential coils and used in such punched card machines as a Reproducer. In this application it would be used to check that a reproducer had missing or extra holes from the original. Here it would be fitted with a 1 to 80 column indicator. In our application it has single coils and indicates the stop letter or letters against three banks/chains.