The American Naval Bombe N-530

Letchworth Enigmas



Letchworth Enigmas can be removed for repair or maintenance as one complete assembly. Three screws fix each brush assembly and when the two Jones sockets are removed the whole assembly can be removed from the machine. When refitted each commutator has to be retimed. Each can be rotated around the three slotted lugs and then tightened on each fixing screw.

Letchworth Enigma/Bank

The image below shows two Letchworth Enigmas fitted to the machine. In this case, the reflector cables are not shown fitted

The image, below, shows a reflector cable that is made up of two 27 way (26 used) Jones plugs with the wires connected to make the appropriate cross-connections

Jones 300 Series Plugs and Sockets

The N-530 uses these in most locations. The numbering system has the prefix P for plug and S for the socket. The number after the 3 is the number of connections. There are only two mouldings of each type and either moulding can be mounted in a rectangular hole in a chassis with additional fixings.

This has the suffix AB

Also, they can be made with a cover and clamp fitted into a flying lead housing a multi-way cable

Other versions may be used occasionally on N-530. The most used is 327 with 27 pins or sockets, where 26-way connections are used to cover the whole alphabet.

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