Cherry Ripe is the nickname of a discontinued
shortwave numbers station
A numbers station is a shortwave radio station characterized by broadcasts of formatted numbers, which are believed to be addressed to intelligence officers operating in foreign countries. Most identified stations use speech synthesis to vocal ...
that used several bars from the
folk song "
Cherry Ripe" as an
interval signal
An interval signal, or tuning signal, is a characteristic sound or musical phrase used in international broadcasting, numbers stations, and by some domestic broadcasters, played before commencement or during breaks in transmission, but most co ...
. The station, which appears to have commenced transmissions in the late 1960s, is believed to have been controlled by the British
Secret Intelligence Service. It is thought to have originally broadcast from a base on
Guam
Guam (; ch, Guåhan ) is an organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. It is the westernmost point and territory of the United States (reckoned from the geographic cent ...
(a US territory), but moved to
Australia in 2009.
Broadcasts from Cherry Ripe consisted of an electronically synthesised, English-accented female voice, reading groups of five numbers, e.g. "3-5-7-6-1". The final number in each group was spoken at a higher pitch. It is likely that the station was used to communicate messages to undercover agents operating in other countries, to be decoded using a
one-time pad
In cryptography, the one-time pad (OTP) is an encryption technique that cannot be cracked, but requires the use of a single-use pre-shared key that is not smaller than the message being sent. In this technique, a plaintext is paired with a ran ...
.
A better-known and more active counterpart, known as the
Lincolnshire Poacher, also after an English folk song used as its interval signal, was broadcast from the
eastern Mediterranean from the early 1970s until 2008. Many aspects of both stations' broadcasts were identical. The Lincolnshire Poacher used the same synthesised female voice and was also suspected as being operated by the UK government. From unofficial triangulation, its location was determined to be
RAF Akrotiri
RAF Akrotiri ( el, Βασιλική Πολεμική Αεροπορία Ακρωτηρίου) is a large Royal Air Force base on the Mediterranean island of Cyprus. It is located in the Western Sovereign Base Area, one of two areas which compr ...
, on
Cyprus
Cyprus ; tr, Kıbrıs (), officially the Republic of Cyprus,, , lit: Republic of Cyprus is an island country located south of the Anatolian Peninsula in the eastern Mediterranean Sea. Its continental position is disputed; while it is ge ...
. Cherry Ripe appeared to assume at least part of the role of the Lincolnshire Poacher, after the latter ceased transmission.
In September 2009, the transmitter for Cherry Ripe was moved to
Humpty Doo
Humpty Doo is a small town in Australia's Northern Territory, situated just south of the Arnhem Highway, approximately 40 km from Darwin. At the , Humpty Doo had a population of 4,380 people. Its local government area is Litchfield Munici ...
, in Australia.
However, in December that year, Cherry Ripe also ceased transmissions.
Schedule
This schedule was accurate as of January 2006. All times are
UTC, frequencies in
MHz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...
.
References
External links
E03a/Ex E04 - Cherry RipeCherry Ripe
on th
Global Frequency Database
on SpyNumbers
*
* includes recording
Secret broadcasting
{{Australia-radio-station-stub