Cableforms – Menu and Cross And Connect Units
Menu cables consist of 26 wires plaited into three groups of 9, 9 and 8. There are 75 of these of which three are extra long to reach back to the ‘input’ jacks. Each cable is terminated at each end with a 26 way Jack.
When plugging up a menu there are many occasions where more than two cables need to be plugged to more than two ‘nodes’. This is often the case but making just three connections is a frequent occurrence. There are two ways of making multiple connections. There are groups of isolated ‘commons’ where 4 or 5 jacks are connected in parallel. The second method is the use a ‘Cross And Connect Unit’. Here this unit is inserted between the output of one Letchworth Enigma and the Input of the next. In the example below 18 ‘out’ to 19 ‘in’. A third cable can then be connected to the same point. This would normally go back to a diagonal board. This method will only work if the WRNS assigned the enigmas to the menu in a serial fashion.
Below it is just possible to see a cable plugged into a Cross And Connect unit and others plugged directly into 19 ‘out’ and 20 ‘in’.