The BC-610 was a

radio Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transm ...

transmitter In electronics and telecommunications, a radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to ...

based on the Hallicrafters HT-4 and was used by the U.S. Army Signal Corps during

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 World War II by country, vast majority of the world's countries—including all of the great power ...

History

In the early 1940s, the U.S. military sought a high-powered radio transmitter capable of infallible voice communications over 100 miles (160 km), sturdy enough to work in all conditions, flexible enough to be able to cover a wide range of frequencies, self-powered and able to operate in motion or at fixed locations. The Hallicrafters HT-4 transmitter was chosen from units available from various U.S. radio manufacturers. The HT-4 was designed for

amateur radio Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communi ...

use and had been commercially available for several years at a price of approximately $700, rivaling the cost of a car. It was considered compact and stable for its era and could deliver in excess of 300

watt The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James Wa ...

s of power for voice or MCW communications and 400 watts during

Morse code Morse code is a method used in telecommunication to encode text characters as standardized sequences of two different signal durations, called ''dots'' and ''dashes'', or ''dits'' and ''dahs''. Morse code is named after Samuel Morse, one ...

operation. As was typical in physically large vacuum tube equipment, the manual cautions power output is less at higher frequencies. It was quartz crystal controlled, but could be used over a wide range of frequencies through use of the master-oscillator power amplifier. Modifications requested by the Signal Corps were performed by Hallicrafters' engineers working with U.S. Army technicians at Fort Monmouth. They made a new version of the HT-4, which was known as the BC-610 transmitter, a part of the SCR-299 mobile communications unit, and production began in 1942. General Dwight Eisenhower credited the SCR-299 in the reorganization of U.S. forces, which led to their victory against the

Nazi Nazism ( ; german: Nazismus), the common name in English for National Socialism (german: Nationalsozialismus, ), is the far-right politics, far-right Totalitarianism, totalitarian political ideology and practices associated with Adolf Hit ...

s at

Kasserine Pass The Battle of Kasserine Pass was a series of battles of the Tunisian campaign of World War II that took place in February 1943 at Kasserine Pass, a gap in the Grand Dorsal chain of the Atlas Mountains in west central Tunisia. The Axis forces, ...

. The SCR-299 was also used in the Invasion of Sicily and later, Italy. A BC-610 transmitter was used by

double agent In the field of counterintelligence, a double agent is an employee of a secret intelligence service for one country, whose primary purpose is to spy on a target organization of another country, but who is now spying on their own country's organ ...

Juan Pujol García during

WWII 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 World War II by country, vast majority of the world's countries—including all of the great power ...

as part of

Operation Fortitude Operation Fortitude was the code name for a World War II military deception employed by the Allied nations as part of an overall deception strategy (code named ''Operation Bodyguard, Bodyguard'') during the build-up to the 1944 Normandy landi ...

. Clear reception by the Germans of messages transmitted by García, code name GARBO, were so crucial to the Allied deception that use of the relatively high-powered transmitter was deemed necessary.
British Intelligence in the Second World War: Volume 4, Security and Counter-Intelligence
'. Cambridge University Press; 31 August 1990. . p. 312–. Over 25,000 units were produced by Hallicrafters and other allied companies. In 1944, a

short subject A short film is any motion picture that is short enough in running time not to be considered a feature film. 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 ...

film was produced by the

Jam Handy Organization Jam is a type of fruit preserve. Jam or Jammed may also refer to: Other common meanings * A firearm malfunction * Block signals ** Radio jamming ** Radar jamming and deception ** Mobile phone jammer ** Echolocation jamming Arts and enterta ...

and sponsored by the Hallicrafters Company detailing how the HT-4 transmitter was adapted for military service and dramatizing its use by the U.S. military during World War II.

Specifications

* Frequency coverage: 2 to 18 MHz * Mode: AM, CW * RF power Output: <400

s CW, <300 watts AM, MCW *

Vacuum tube A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. The type kn ...

s: Eimac 250TH final, pair 100TH modulator, various rectifier and low level tubes * Operating frequency determined by plug-in tuning units and final coils (up to three at once) in addition to FT-171B crystals *

Signal Corps Radio Signal Corps Radios were U.S. Army military communications components that comprised "sets". Under the Army Nomenclature System, the abbreviation SCR initially designated "Set, Complete Radio", but was later misinterpreted as "Signal Corps Radio." ...

sets: SCR-299, SCR-399, SCR-499, or GRC-38, AM requires BC-614 (or Hallicrafters HT-5) speech amplifier * Weight: 390 lb (177 kg) (without BC-614) * Manual: TM 11-280 The "A" through "I" models are the same basic unit with relatively minor component and cosmetic differences.{{cite web, title=HT-4 / BC-610, url=http://www.radiomuseum.org/r/hallicraft_ht_4_ht4.html, website=Radio Museum, publisher=radiomuseum.org, accessdate=29 June 2017

References

External links

''Hallicrafters, The Voice Of Victory'' (1944)
Internet Archive, Part 1
''Hallicrafters, The Voice Of Victory'' (1944)
Internet Archive, Part 2

Military radio systems of the United States World War II American electronics Military equipment introduced from 1940 to 1944

History

Specifications

See also

References

External links