Monument record 0942000000 - Signal Hill Transmitter Station

World War II radio transmitter station used for Foreign Office broadcasts. Site recorded for Defence of Britain project, included a brick transmitter building, built by a local contractor. Condition recorded as good during field visits in September and November 1996 (B1).
After war, thought to be used as an MI6 Signals Intelligence (SIGINT) site, possibly a 'Numbers Station' transmitting encoded shortwave messages to MI6 agents (B2).
Radio masts dismantled after October 1988 (visible on BCC vertical AP) and before 1999 (B3).
Harold Robin was asked in 1940 to find a suitable site to build a shortwave radio station to transmitt propaganda in German and he chose a large field at Gawcott. Approached by a gravel path and a four-foot high barbed wire fence surrounded the site. Personnel were accomodated at lodgings in the village. Initially one transmitter was accomodated at the site, called Geranium, housed in a wooden building. A second transmitter, called Gardenia, was bought in December 1941 and when it arrived it was housed in a brick building 350 yards from the wooden one. Both buildings were surrounded by brick built blast walls. Midway between was a small brick structure where the telephone line terminated. This was also an office for the officer on site. Next to each transmitter was a brick built powerhouse, each containing a diesel powered generator. Pre-recorded broadcasts on glass discs were brought every day from the studios at Whaddon Hall and later Wavendon Towers until Geranium was linked by landline to another studio and the work involved monitoring the broadcast. Gardenia started transmitting morse in late 1944 to S.H.A.E.F, the special operatives executive, using the telephone lines. After the war the radio station was expanded and remained in Government use until recently. Today the site accommodates a number of small businesses (B4,B6).