SCR-299
Encyclopedia
The SCR-299 was a U.S. Signal Corps mobile military communications
unit used during World War II
.
and SCR-597, and was an effort to give a long-range communication advantage to the U.S. Army and its allies. To meet these demands, a high-powered radio transmitter was required — capable of infallible voice communications over 100 miles (160.9 km); self-powered; sturdy enough to work in all conditions, flexible enough to cover a wide range of frequencies; and able to operate in motion or at fixed locations.
Production began in early spring 1942. Out of the various sets sent from U.S. vendors, and after considerable experimentation, Hallicrafters
Standard HT-4 transmitter was chosen as the desired radio's basis. The HT-4 transmitter's new version became known as the BC-610
transmitter. The receivers finally supplied were the BC-312
and BC-342
, plus the BC-614 (speech amplifier), BC-729 (tuning unit) and BC-211 (frequency meter), along with the PE-95 (power unit). All these became part of the truck-and- trailer unit called the SCR-299 — later better known as the "mobile communications unit."
SCR-299 was updated to version SCR-399, similar to the SCR-299 except it was installed in an HO-17 shelter designed to be mountable in vehicles such as 2-ton trucks and accompanied by the power unit carried in a K-52 trailer. An air transportable version, the SCR-499 was developed and became standard for the USAAF. Hallicrafters Company advertising of the period sometimes used illustrations of the shelter-mounted SCR-399 to describe the achievements of the SCR-299.
On Nov. 8, 1942, amphibious landings of British
and American forces for Operation TORCH
presented the Signal Corps and the SCR-299 with its first major test of the war. Companies of the 829th Signal Service Battalion assigned to each task force attempted to set up the administrative communications net with SCR-299 truck and trailer radio sets immediately upon landing. The plan was to connect the widely separated landing areas and to communicate with Gibraltar
. Unfortunately, the weighty sets had been stowed deep in the holds of the convoy ships and only one could be unloaded in time for use during the initial assault. Luckily, British communications ships filled the gap until the SCR-299's could be landed. Once onshore, the sets provided the chief means of long-distance signals until permanent Army Command and Administrative Network stations could be installed. General Dwight Eisenhower credited the SCR-299 in his successful reorganization of the American forces and final defeat of the Nazis at Kasserine Pass.
Though the original Signal Corps requirements were for communication points up to 100 miles (160.9 km), under favorable conditions these transmitters made and maintained contact over 2300 miles (3,701.5 km) of land and sea. During the North African campaign
, a Signal Corps battalion took advantage of the SCR-299 and long distance skywave
propagation to establish a direct radio telegraph channel to England
. On D-Day
an SCR-499 housed in a quarter ton trailer designed to be hauled by a jeep arrived in Normandy via glider
and immediately went into service to link between two airborne divisions with Britain
. The SCR-299 was also used in the invasion of Sicily and the Allied invasion of Italy
.
The SCR-299/399 received fairly heavy use by war correspondents and members of the press corps. During the Normandy landings, the US Second Army and US Third Army Group Communications Team provided SCR-399 sets for transmitting press copy to London
. When the Normandy Breakout
came, Third Army began moving so fast that there was no possibility of putting in a teleprinter circuit from Third Army headquarters back to London and the SCR-399 became the only means of getting press copy direct to London.
In 1944, a short subject
film was produced by the Jam Handy Organization and sponsored by the Hallicrafters Company that showed the construction of the SCR-299 and dramatized its use during World War II.
The SCR-299 was a complete mobile HF
station on frequencies from 2 to 8 MHz (and 1–18 MHz using conversion kits) with transmitter output of 350 watt
s. The entire unit came in a K-51 truck except Power Unit PE-95 which was in a K-52 trailer. Power could either be supplied by the Power Unit and a 12 volt storage battery, or 115 volt 60 cycle AC commercial power and two spare 6 volt storage batteries. The power requirement was 2000 watts, plus 1500 watts for heater and lights.
The system could be remotely controlled up to a distance of one mile (1.6 km) using two EE-8 field telephones and W-110-B Wire kit. Remote equipment was provided for remotely keying or voice modulating the transmitter, remotely listening to the receiver, and for communicating with the operator of the station.
Frequency Conversion Kit MC-503 gave coverage down to 1 MHz. Frequency Conversion Kit MC-516 gave coverage to 12 MHz and Frequency Conversion Kit MC-517 gave coverage to 18 MHz. The receiver used a 9 feet (2.7 m) whip antenna and the transmitter used a 15 feet (4.6 m) whip antenna while moving. Alternately, it could use a 21 ft (6.4 m) whip antenna while stationary or a 45 ft (13.7 m) auxiliary wire antenna for 2.0 to 4.5 MHz coverage.
Military communications
Historically, the first military communications had the form of sending/receiving simple signals . Respectively, the first distinctive tactics of military communications were called Signals, while units specializing in those tactics received the Signal Corps name...
unit used during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
.
History
The SCR-299 replaced SCR-197SCR-197
The SCR-197 was a ground mobile high frequency radio station used by the United States military prior to and during World War II, notably during the Battle of Wake Island in 1941.-Specifications:...
and SCR-597, and was an effort to give a long-range communication advantage to the U.S. Army and its allies. To meet these demands, a high-powered radio transmitter was required — capable of infallible voice communications over 100 miles (160.9 km); self-powered; sturdy enough to work in all conditions, flexible enough to cover a wide range of frequencies; and able to operate in motion or at fixed locations.
Production began in early spring 1942. Out of the various sets sent from U.S. vendors, and after considerable experimentation, Hallicrafters
Hallicrafters
The Hallicrafters Company manufactured, marketed, and sold radio equipment beginning in 1932. The company was based in Chicago, Illinois, USA.-History:William J. Halligan founded his own radio manufacturing company in Chicago in late 1932...
Standard HT-4 transmitter was chosen as the desired radio's basis. The HT-4 transmitter's new version became known as the BC-610
BC-610
The BC-610 was a radio transmitter used by the U.S. Army Signal Corps during World War II.-History:In the early 1940s, the U.S. military sought a high-powered radio transmitter capable of infallible voice communications over 100 miles , sturdy enough to work in all conditions, flexible enough to...
transmitter. The receivers finally supplied were the BC-312
BC-342
The BC-342 was a World War II U.S. Army Signal Corps radio receiver with high frequency band coverage. It was a 115 Volt AC version of the BC-312 receiver, used primarily as part of field installations...
and BC-342
BC-342
The BC-342 was a World War II U.S. Army Signal Corps radio receiver with high frequency band coverage. It was a 115 Volt AC version of the BC-312 receiver, used primarily as part of field installations...
, plus the BC-614 (speech amplifier), BC-729 (tuning unit) and BC-211 (frequency meter), along with the PE-95 (power unit). All these became part of the truck-and- trailer unit called the SCR-299 — later better known as the "mobile communications unit."
SCR-299 was updated to version SCR-399, similar to the SCR-299 except it was installed in an HO-17 shelter designed to be mountable in vehicles such as 2-ton trucks and accompanied by the power unit carried in a K-52 trailer. An air transportable version, the SCR-499 was developed and became standard for the USAAF. Hallicrafters Company advertising of the period sometimes used illustrations of the shelter-mounted SCR-399 to describe the achievements of the SCR-299.
On Nov. 8, 1942, amphibious landings of British
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
and American forces for Operation TORCH
Operation Torch
Operation Torch was the British-American invasion of French North Africa in World War II during the North African Campaign, started on 8 November 1942....
presented the Signal Corps and the SCR-299 with its first major test of the war. Companies of the 829th Signal Service Battalion assigned to each task force attempted to set up the administrative communications net with SCR-299 truck and trailer radio sets immediately upon landing. The plan was to connect the widely separated landing areas and to communicate with Gibraltar
Gibraltar
Gibraltar is a British overseas territory located on the southern end of the Iberian Peninsula at the entrance of the Mediterranean. A peninsula with an area of , it has a northern border with Andalusia, Spain. The Rock of Gibraltar is the major landmark of the region...
. Unfortunately, the weighty sets had been stowed deep in the holds of the convoy ships and only one could be unloaded in time for use during the initial assault. Luckily, British communications ships filled the gap until the SCR-299's could be landed. Once onshore, the sets provided the chief means of long-distance signals until permanent Army Command and Administrative Network stations could be installed. General Dwight Eisenhower credited the SCR-299 in his successful reorganization of the American forces and final defeat of the Nazis at Kasserine Pass.
North African campaign
During the Second World War, the North African Campaign took place in North Africa from 10 June 1940 to 13 May 1943. It included campaigns fought in the Libyan and Egyptian deserts and in Morocco and Algeria and Tunisia .The campaign was fought between the Allies and Axis powers, many of whom had...
, a Signal Corps battalion took advantage of the SCR-299 and long distance skywave
Skywave
Skywave is the propagation of electromagnetic waves bent back to the Earth's surface by the ionosphere. As a result of skywave propagation, a broadcast signal from a distant AM broadcasting station at night, or from a shortwave radio station can sometimes be heard as clearly as local...
propagation to establish a direct radio telegraph channel to England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
. On D-Day
D-Day
D-Day is a term often used in military parlance to denote the day on which a combat attack or operation is to be initiated. "D-Day" often represents a variable, designating the day upon which some significant event will occur or has occurred; see Military designation of days and hours for similar...
an SCR-499 housed in a quarter ton trailer designed to be hauled by a jeep arrived in Normandy via glider
Military glider
Military gliders have been used by the military of various countries for carrying troops and heavy equipment to a combat zone, mainly during the Second World War. These engineless aircraft were towed into the air and most of the way to their target by military transport planes, e.g...
and immediately went into service to link between two airborne divisions with Britain
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
. The SCR-299 was also used in the invasion of Sicily and the Allied invasion of Italy
Allied invasion of Italy
The Allied invasion of Italy was the Allied landing on mainland Italy on September 3, 1943, by General Harold Alexander's 15th Army Group during the Second World War. The operation followed the successful invasion of Sicily during the Italian Campaign...
.
The SCR-299/399 received fairly heavy use by war correspondents and members of the press corps. During the Normandy landings, the US Second Army and US Third Army Group Communications Team provided SCR-399 sets for transmitting press copy to London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
. When the Normandy Breakout
Operation Cobra
Operation Cobra was the codename for an offensive launched by the First United States Army seven weeks after the D-Day landings, during the Normandy Campaign of World War II...
came, Third Army began moving so fast that there was no possibility of putting in a teleprinter circuit from Third Army headquarters back to London and the SCR-399 became the only means of getting press copy direct to London.
In 1944, a short subject
Short subject
A short film is any film not long enough to be considered a feature film. No consensus exists as to where that boundary is drawn: the Academy of Motion Picture Arts and Sciences defines a short film as "an original motion picture that has a running time of 40 minutes or less, including all...
film was produced by the Jam Handy Organization and sponsored by the Hallicrafters Company that showed the construction of the SCR-299 and dramatized its use during World War II.
Specifications
High frequency
High frequency radio frequencies are between 3 and 30 MHz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters . Frequencies immediately below HF are denoted Medium-frequency , and the next higher frequencies are known as Very high frequency...
station on frequencies from 2 to 8 MHz (and 1–18 MHz using conversion kits) with transmitter output of 350 watt
Watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
s. The entire unit came in a K-51 truck except Power Unit PE-95 which was in a K-52 trailer. Power could either be supplied by the Power Unit and a 12 volt storage battery, or 115 volt 60 cycle AC commercial power and two spare 6 volt storage batteries. The power requirement was 2000 watts, plus 1500 watts for heater and lights.
The system could be remotely controlled up to a distance of one mile (1.6 km) using two EE-8 field telephones and W-110-B Wire kit. Remote equipment was provided for remotely keying or voice modulating the transmitter, remotely listening to the receiver, and for communicating with the operator of the station.
Frequency Conversion Kit MC-503 gave coverage down to 1 MHz. Frequency Conversion Kit MC-516 gave coverage to 12 MHz and Frequency Conversion Kit MC-517 gave coverage to 18 MHz. The receiver used a 9 feet (2.7 m) whip antenna and the transmitter used a 15 feet (4.6 m) whip antenna while moving. Alternately, it could use a 21 ft (6.4 m) whip antenna while stationary or a 45 ft (13.7 m) auxiliary wire antenna for 2.0 to 4.5 MHz coverage.
See also
- ARC-5ARC-5The AN/ARC-5 Command Radio Set is a series of radio receivers, transmitters, and accessories used to provide two-way Morse code and AM radiotelephone communication for U.S. Navy aircraft during World War II and the years following. It was an improvement of the Navy's ARA/ATA command set. Similar...
- BC-348BC-348The BC-348 is a compact American-made communications receiver, which was mass-produced during World War II for the U.S. Army Air Force. Under the Joint Army-Navy nomenclature system, the receiver system became known as the AN/ARR-11. -History:...
- BC-654BC-654The SCR-284 was a World War II era combination transmitter and receiver used in vehicles or fixed ground stations.- History :The Crosley Corporation of Cincinnati, Ohio manufactured the Signal Corps Radio set SCR-284 that consisted of the BC-654 and associated support equipment.The BC-654 first saw...
- BC-610BC-610The BC-610 was a radio transmitter used by the U.S. Army Signal Corps during World War II.-History:In the early 1940s, the U.S. military sought a high-powered radio transmitter capable of infallible voice communications over 100 miles , sturdy enough to work in all conditions, flexible enough to...
- Collins Radio
- Hallicrafters SX-28Hallicrafters SX-28The Hallicrafters SX-28 "Super Skyrider" was an American shortwave communications receiver produced between 1940 and 1946 that saw wide use by amateur radio, government and military services.-History:...
- R-390AR-390AThe R-390A /URR is a general coverage HF radio communications receiver designed by Collins Radio Company for the US military.-History:The R-390A military shortwave radio receiver was the result of a project undertaken by the U. S. Army Signal Corps in 1954 to replace the existing R-390 receiver...
- SCR-300SCR-300The SCR-300 was a portable radio transceiver used by US Signal Corps in World War II. This backpack-mounted unit was the first two way radio to be nicknamed a "walkie talkie".- History :...
- Wireless Set No. 19Wireless Set No. 19The Wireless Set No. 19 was a Second World War mobile radio transceiver designed for the British Army to give armoured troops reliable communications.- Specifications :...
- List of U.S. Signal Corps Vehicles
- Signal Corps RadioSignal Corps RadioSignal Corps Radios were U.S. Army military communications components that comprised "sets". Under the Army Nomenclature System, SCR initially designated "Set, Complete Radio," and later "Signal Corps Radio," though interpretations have varied over time....
- M-209M-209In cryptography, the M-209, designated CSP-1500 by the Navy is a portable, mechanical cipher machine used by the US military primarily in World War II, though it remained in active use through the Korean War...