Secret broadcast

A secret broadcast is, simply put, a broadcast that is not for the consumption of the general public. The invention of the wireless was initially greeted as a boon by armies and navies. Units could now be coordinated by nearly instant communications. An adversary could glean valuable and sometimes decisive intelligence from intercepted radio signals.
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==Related topics==
Based upon the Wikipedia category list Secret Broadcasting
===Diplomatic Telecommunications Service===
The Diplomatic Telecommunications Service (DTS) is a system of integrated telecommunications networks that supports foreign affairs agencies in Washington, D.C., and U.S. diplomatic missions abroad. It is administered by the United States Department of State Diplomatic Telecommunications Service Program Office (DTSPO). DTS is a global network of telecommunications sites that is charged with providing a global, reliable, and cost-effective communications network for the U.S. foreign affairs community
Wikipedia page which has a list of relay stations refers.
===Cherry Ripe (numbers station)===
Cherry Ripe was the nickname of a mysterious, powerful shortwave numbers station that used several bars from the English folk song "Cherry Ripe" as an interval signal. The station was believed to be operated by the British Secret Intelligence Service and to have emanated from Australia. It was thought to have previously broadcast from Guam. It consisted of an electronically synthesised English-accented female voice reading groups of five numbers, e.g. "3-5-7-6-1". 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 December 2009 Cherry Ripe also went offline.
Wikipedia page refers.
===The Conet Project===
The Conet Project: Recordings of Shortwave Numbers Stations is a four (later five) CD set of recordings of numbers stations and noise stations: mysterious shortwave radio stations of uncertain origin believed to be operated by government agencies to communicate with deployed spies. The collection is released by Britain's Irdial-Discs record label in 1997, based on the work of numbers station enthusiast Akin Fernandez.
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===Letter beacon===
Letter beacons are radio transmissions of uncertain origin and unknown purpose, consisting of only a single repeating Morse code letter. They have been classified into a number of groups according to transmission code and frequency, and it is supposed that the source for most of them is Russia.
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===Lincolnshire Poacher (numbers station)===
"The Lincolnshire Poacher" was a powerful shortwave numbers station that transmitted by Cyprus from the mid-1970s to June 2008. The station gained its commonly known name as it uses bars from the English folk song "The Lincolnshire Poacher" as an interval signal. The radio station was believed to be operated by the British Secret Intelligence Service and emanated from the island of Cyprus. Amateur direction finding had linked it with the Royal Air Force base at Akrotiri, Cyprus, where several curtain antennas had been identified as being its transmitter.
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===Numbers station===
A numbers station is a type of shortwave radio station characterized by unusual broadcasts, reading out lists of numbers or incomprehensible coded messages. The voices are often created by speech synthesis and are transmitted in a wide variety of languages. 
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===The Pip===
The Pip is the nickname given by radio listeners to a shortwave radio station that broadcasts on the frequency 5448 kHz by day, and 3756 kHz during the night.[1][2] It broadcasts short, repeated beeps at a rate of around 50 per minute, for 24 hours per day. The beep signal is occasionally interrupted for voice messages in Russian. The Pip has been active since around 1986, when its distinctive beeping sound was first recorded by listeners.
Wikipedia page refers.
===The Squeaky Wheel===
The Squeaky Wheel is the nickname given by radio listeners to a utility shortwave radio station that used to broadcast a distinctive sound. From around 2000 until 2008 this station sounded much like a squeaky wheel. From 2008 the channel marker changed to two different tones in a short sequence repeated with a short silent gap. 
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===UVB-76===
UVB-76, also known as '"the Buzzer", is the nickname given by radio listeners to a shortwave radio station that broadcasts on the frequency 4625 kHz. It broadcasts a short, monotonous About this sound buzz tone (help·info), repeating at a rate of approximately 25 tones per minute, for 24 hours per day. On very rare occasions, the buzzer signal is interrupted and a voice transmission in Russian takes place. The first reports were made of a station on this frequency in 1982. Its origins have been traced to Russia, and although several theories with varying degrees of plausibility exist, its actual purpose has never been officially confirmed and remains a source of speculation.
Wikipedia page refers.
===Yosemite Sam (shortwave)===
Yosemite Sam is the nickname given by DXers to a number station that first surfaced on December 19, 2004. It transmits on several shortwave frequencies in dual side band: 3700 kHz, 4300 kHz, 6500 kHz, and 10500 kHz. The nickname is taken from the Looney Tunes character Yosemite Sam, whose voice is played as part of the unusual transmission.
Wikipedia page refers.
Category:20th century
Category:21st century
Category:Radio stations