The Wireless Set Number 11, or WS No. 11, was a radio set designed for the British Army in 1938. It was designed to replace the 1933 Wireless Set No. 1 which had been found inadequate for a number of reasons. Like the No. 1, it was designed to be used in fixed locations like regimental field headquarters, as well as in vehicles and tanks.
Some No. 11s were produced between 1938 and 1940 before they, too, were considered inadequate. A smaller production run in Canada was also completed by Canadian Marconi and used both by Canadian and British forces. The No. 11 was replaced in tanks by the significantly more capable Wireless Set No. 19, while the No. 11 went on to be used by many others, notably the Long Range Desert Group.