Throughout history, many inventions and developments have occurred - by necessity - as the result of wars.
At the start of WW1, huge lumbering airships (the length of 2 football pitches and filled with highly flammable hydrogen gas) were in regular use. In Britain, their main function was in patrol work, spotting the movement of enemy shipping and locating artillery shots.
This information was then relayed back to base in Morse code by the wireless operator, via a wave (or ‘spark’) transmitter.... not a particularly good idea, to produce sparks close to a gas-bag containing one million cubic feet of hydrogen, but valves were only in the development stage, so spark transmitters were still widely used.
However, by 1916, valves had been fitted to the portable ‘continuous wave transmitters and receivers’ that were used in the 'forward areas' (trenches). These trench sets had a range of about two miles but required a 'volunteer'(?) to go 'over the top' and lay out the 100 feet long aerial.
As the war progressed, the increasing use of radio led to rapid developments in valves, so that by 1918, the valved wireless had superseded the spark transmitter and was in general use.
The development of the valve brought speech, and revolutionised radio communications, so that within twenty years, complex transceivers were being assembled for use in WW2. Throughout WW2, the role of radio was vital - providing light relief as well as relaying the latest developments and news from 'the front'.
Clandestine radio played an important role as well. "The spy set" was a 4-valve battery set with plug-in coils, produced by the Philco Radio Company. Packed in Huntley & Palmer biscuit tins, thirty thousand of these sets were dropped at night to resistance fighters in enemy occupied countries. Known to the French Resistance as "Radio Biscuite"!
In the war years, enormous advances were made with the development of ground, air and submarine devices, using radio, radar and sonar equipment.
A badly dented 1938 German 'EK' receiver is another of the Museum's 'treasures'. It was recovered from the wreckage of a Heinkel 111, shot down in an attack on warships anchored near the Forth Bridge during the first air raid of the war on 16 October 1939. It carries the marks of machine gun bullets, fired from the attacking Spitfire of 602 Squadron.