BC-611 Radio Transmitter-Receiver - National Cryptologic Museum - DSC07810

The SCR-536 was a hand-held

radio Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connec ...

transceiver In radio communication, a transceiver is an electronic device which is a combination of a radio ''trans''mitter and a re''ceiver'', hence the name. It can both transmit and receive radio waves using an antenna, for communication purposes. The ...

used by the US Army Signal Corps in

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. It is popularly referred to as a walkie talkie, although it was originally designated a "handie talkie".

History

The SCR-536 is often considered the first of modern hand-held, self-contained, "handie talkie"

s (two-way radios). It was developed in 1940 by a team led by Don Mitchell, chief engineer for Galvin Manufacturing (now

Motorola Solutions Motorola Solutions, Inc. is an American technology, communications, and security company, headquartered in Chicago, Chicago, Illinois. It is the legal successor of Motorola, Inc., following the spinoff of the mobile phone division into Motorola ...

) and was the first true hand-held unit to see widespread use. By July 1941, it was in mass production. In November 1942, the SCR-536 received coverage in the

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

magazine QST. It appeared on the cover as well as in Signal Corps advertising, and was featured as part of an article on the Signal Corps, "Smallest field unit of the Signal Corps", in which a photo caption read: "it is not much larger or heavier than a conventional handset". It was carried among the first waves to hit

Omaha Beach Omaha Beach was one of five beach landing sectors of the amphibious assault component of Operation Overlord during the Second World War. On June 6, 1944, the Allies of World War II, Allies invaded German military administration in occupied Fra ...

Normandy Normandy (; or ) is a geographical and cultural region in northwestern Europe, roughly coextensive with the historical Duchy of Normandy. Normandy comprises Normandy (administrative region), mainland Normandy (a part of France) and insular N ...

in June 1944 (and in

Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...

Sicily Sicily (Italian language, Italian and ), officially the Sicilian Region (), is an island in the central Mediterranean Sea, south of the Italian Peninsula in continental Europe and is one of the 20 regions of Italy, regions of Italy. With 4. ...

and

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before that). Every rifle company of the U.S. 29th Infantry division had six; one for each of the three rifle platoons, two for the weapons platoon, and one for the company CO. The Germans were deeply impressed by the SCR-536 and the SCR-300 after capturing several units in

. By war’s end, 130,000 of the units had been manufactured by

Motorola Motorola, Inc. () was an American multinational telecommunications company based in Schaumburg, Illinois. It was founded by brothers Paul and Joseph Galvin in 1928 and had been named Motorola since 1947. Many of Motorola's products had been ...

. They were also produced by other firms. Today, the SCR-536 is often restored and operated by vintage amateur radio enthusiasts and military radio collectors.

Specifications

The SCR-536 incorporated five

vacuum tube A vacuum tube, electron tube, thermionic 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. It ...

s in a waterproof case. There was no external power switch on the SCR-536. The operator pulled out or pushed in the antenna on the top which operated an internal switch to turn the radio on or off. The power was supplied by a BA-37 1.5 volt dry battery for the filament supply and a 103.5 V BA-38 battery for plate supply. Battery life was about one day of normal use. The SCR-536 weighed 5 pounds (2.3 kg) with batteries and 3.85 lb (1.75 kg) without batteries. The unit operated in AM voice mode between 3.5 and 6.0

MHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose formal expression in terms of SI base u ...

frequency range on any one of 50 channels. Plug in crystals and coils were used to control the frequency of the receiver and transmitter. The antenna was a 40 inch (102 cm) telescoping rod that slid into the case. The SCR-536 had an RF output power of 360

milliwatt 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 in honor o ...

s. The range of the unit varied with terrain; from a few hundred feet (about a hundred metres), to approximately one mile (1.5 km) over land, and 3 miles (5 km) over water. Under the Army Nomenclature System, the BC-611 transceiver was the core component of the SCR-536 Signal Corps Radio set. The Signal Corps technical manual number was TM 11-235.

Components

* BX-48 box for spare crystals and tubes (5 sets) * BX-49 box for spare crystals and tubes (24 sets) * BG-162 bag for batteries (BA-37, BA-38) * CH-146 chest for equipment * CH-233 chest for spare tubes, crystals, (400 items) * CS-144 parachute case * CS-156 canvas case * CH-312 case for IE-37 tuning unit

References

External links

{{commonscat
War Department Manual, ''Radio Sets SCR-536-A, -B, -C, -D, -E-, and -F'', Mai 1945
* https://www.youtube.com/watch?v=Pn2xOEuvax4 Radio systems of the United States Army World War II American electronics Military equipment introduced in the 1940s Models of radios Military electronics of the United States

History

Specifications

Components

See also

References

External links