© 2008 Museum of Communication

This section is dedicated to wartime equipment from the Armed Services. Two exhibits on display date from WW1. The "Spark Transmitter" was originally fitted to an airship, where it produced sparks within a few feet of the (usually leaking) hydrogen filled gas bag..... During WW1, airships were used for patrol work, to spot the movement of enemy shipping and locate artillery shots. This information was transmitted back to Base in Morse code by the Wireless Operator on board the airship. As valves were only in the development stage, spark transmitters were still widely used.

However, valves were fitted to the portable transmitters and receivers in the trenches. On view is the Trench Set Transmitter, which had a range of about two miles and required a "Volunteer" to go 'over the top' and lay out the 100 feet long aerial.

The development of the valve revolutionised radio communications and within twenty years, complex transceivers were being assembled for use in WW2. The display shows an Infantry back-pack Wireless Set No. 18, weighing about 10 kg. and the sophisticated Wireless Set No. 19 which was installed in tanks. This particular set was produced for the Russian Front - note the Cyrillic lettering. Tanks, like aircraft, were very noisy and Throat Microphones were worn. These were designed to eliminate background noise by picking up epiglottal vibrations and they also left the hands free.

The remaining items are a Fullerphone - similar to the field telephone but much more secure, as its design prevents "tapping" by the enemy, and finally, the MCR1 ('Miniature Clandestine Radio' or more commonly, 'The Spy Set'). It is shown here in a small attache case, which also contains earphones, aerial wires, heliograph, pencil, paper, comb and cigarette papers! Packed in Huntley & Palmer biscuit tins, thirty thousand of these sets were dropped at night to resistance fighters in enemy occupied countries and were known to the French Resistance as "Radio Biscuite"!