Monitoring Station Designators were used by the

United States Army The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cla ...

Signals Intelligence Service The Signal Intelligence Service (SIS) was the United States Army codebreaking division through World War II. It was founded in 1930 to compile codes for the Army. It was renamed the Signal Security Agency in 1943, and in September 1945, became th ...

to designate a specific signal intelligence monitoring station in order to allow analysts to understand the source and type of

SIGINT Signals intelligence (SIGINT) is intelligence-gathering by interception of ''signals'', whether communications between people (communications intelligence—abbreviated to COMINT) or from electronic signals not directly used in communication ( ...

they were analyzing. These were used as shorthand rather than writing or typing out the PLA (Plain Language Address), which consisted of the formal unit name and location of the unit who performed the signals collection.

Period of Use

These designators were used from the 1930s through the end of

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

. They were replaced after the end of the war with

SIGAD A SIGINT Activity Designator (or SIGAD) identifies a signals intelligence (SIGINT) line of collection activity associated with a signals collection station, such as a base or a ship. For example, the SIGAD for Menwith Hill in the UK is USD1000. S ...

s (SIGINT Activity Designators), which are similar in format and application. Two facilities, Vint Hill and Two Rock Ranch, were operated by the

NSA The National Security Agency (NSA) is a national-level intelligence agency of the United States Department of Defense, under the authority of the Director of National Intelligence (DNI). The NSA is responsible for global monitoring, collectio ...

until the 1970s.

General Format

The general format of the Monitoring Station Designators was the alphabetic characters MS followed by one or two numeric characters. Typically the alphabetic characters and numeric character(s) were separated by a dash character.

Example Designators

The following table provides several examples of Monitoring Station Designators from the World War II era. Sites noted with USA were run by the United States Army, while sites noted with USN were operated by

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

References

{{Reflist Signals intelligence of World War II United States Army Signals Intelligence Service