Monument record 0942000000 - Signal Hill Transmitter Station


World War II radio transmitter at Signal Hill.

Protected Status/Designation

  • None recorded


Type and Period (2)

  • BROADCASTING TRANSMITTER (20th Century - 1900 AD to 1999 AD)
  • TRANSMITTER SITE (Modern - 1939 AD? to 1990 AD?)


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).

Sources (7)

  • ---SBC22611 Aerial Photograph: JASAIR. 1988. 1988 JasAir vertical AP. SP69153175. Yes.
  • <1>SBC22299 Digital archive: Council for British Archaeology. 2002. Defence of Britain database. Anti-invasion record ID 1696.
  • <2>SBC22610 Unpublished document: Alan Turnbull. 2006. Secret Bases website.
  • <3>SBC24044 Verbal communication: 2006. Information from 1988 and 1999 BCC vertical Aps. Yes.
  • <4>SBC22675 Digital archive: 2001. Information from WWII Secret Intelligence Activities Around Milton Keynes website.
  • <5>SBC22801 Bibliographic reference: Pip Brimson. 2001. Buckingham at War.
  • <6>SBC24105 Bibliographic reference: John A Taylor. 2005. Bletchley Park's Secret Sisters: Psychological Warfare in World War II. ppx-xi,23-24,27-29,31-33,49,62.


Grid reference Centred SP 69417 32050 (979m by 677m)
Civil Parish BUCKINGHAM, Aylesbury Vale, Buckinghamshire

Finds (0)

Related Monuments/Buildings (1)

Related Events/Activities (0)

Record last edited

Feb 9 2023 12:40PM

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