Wireless of the Week - week 19

[Bruce Parker (RIP)]

At some point all the various field phones and remote control units have to be linked together into a network and, drawing on the civilian example, switchboards were developed for military use. The British Commonwealth version of this for field use was the Switchboards, U.C. 10-Line and Switchboards, U.C. 6-Line. These switchboards (U.C. standing for ‘Universal Call’) were designed for local office use or at Divisional Signals for the 10 line, and at Battalion and in Artillery Regiments for the 6 line. These switchboards were used throughout the war and as late as the 1980’s in cadet corps.

The units are housed in aluminum cases 8” by 8” by 17” (UC6) and by 21-1/2” (UC10) that have a hinged panel on the front that protects the switchboard controls and acts as a tray that organizes the plugs and pulleys. Another panel on the rear allows access to the wire post connections as well as the internal parts and battery box. On the side is a hinged box that stores the plugs, headset and night alarm when not in use. These boxes may be mounted on either side or removed completely so individual switchboards may be used together. The switchboard itself is made up of modular, replaceable sections that have a B jack on the bottom, an A jack at the top, a numbered lamp to indicate an incoming call (and for testing the unit) as well as a white plastic panel where the operator can write down who is at the other end of that particular wire.

The operator uses a handset or alternatively a breast plate with an attached microphone. A night alarm bell is available to let him monitor the board from some distance away…like his cot. The system has a noise limiter to help with incoming line crackle and switching spikes.

These UC switchboards are very robust and with a few modern D cell batteries in place of the war-era X cells they usually work with no extra tinkering. The remaining question for signals collectors in Canada is why you can still find UC10’s yet UC6’s are almost non-existent.