SCR-536
Encyclopedia
Radio
Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...
transceiver
Transceiver
A transceiver is a device comprising both a transmitter and a receiver which are combined and share common circuitry or a single housing. When no circuitry is common between transmit and receive functions, the device is a transmitter-receiver. The term originated in the early 1920s...
used by US Signal Corps in 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...
. 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" two-way radioTwo-way radio
A two-way radio is a radio that can both transmit and receive , unlike a broadcast receiver which only receives content. The term refers to a personal radio transceiver that allows the operator to have a two-way conversation with other similar radios operating on the same radio frequency...
s. It was developed in 1940 by a team led by Don Mitchell, chief engineer for Galvin Manufacturing (now Motorola
Motorola
Motorola, Inc. was an American multinational telecommunications company based in Schaumburg, Illinois, which was eventually divided into two independent public companies, Motorola Mobility and Motorola Solutions on January 4, 2011, after losing $4.3 billion from 2007 to 2009...
) 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
Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...
magazine QST
QST
QST is a magazine for amateur radio enthusiasts, published by the American Radio Relay League . It is a membership journal that is included in membership with the ARRL. The publisher claims that circulation of QST in the United States is higher than all amateur radio-related publications in the...
. 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
Omaha Beach is the code name for one of the five sectors of the Allied invasion of German-occupied France in the Normandy landings on 6 June 1944, during World War II...
at Normandy
Normandy
Normandy is a geographical region corresponding to the former Duchy of Normandy. It is in France.The continental territory covers 30,627 km² and forms the preponderant part of Normandy and roughly 5% of the territory of France. It is divided for administrative purposes into two régions:...
in June, 1944. Every rifle company of the U.S. 29th Infantry division had six; one for each of three rifle platoons, two for the weapons platoon, and one for the company CO. The German
Germans
The Germans are a Germanic ethnic group native to Central Europe. The English term Germans has referred to the German-speaking population of the Holy Roman Empire since the Late Middle Ages....
s were deeply impressed by the SCR-536 and the SCR-300
SCR-300
The 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 :...
after capturing several units in Sicily
Sicily
Sicily is a region of Italy, and is the largest island in the Mediterranean Sea. Along with the surrounding minor islands, it constitutes an autonomous region of Italy, the Regione Autonoma Siciliana Sicily has a rich and unique culture, especially with regard to the arts, music, literature,...
. By war’s end, 130,000 of the units had been manufactured by Motorola.
Today the SCR-536 is often restored and operated by vintage amateur radio
Vintage amateur radio
Vintage amateur radio is a subset of the amateur radio hobby, considered a form of nostalgia much like antique car collecting, where enthusiasts collect, restore, preserve, build, and operate amateur radio equipment from bygone years, most notably those using vacuum tube technology.Popular modes of...
enthusiasts and military radio collectors.
Specifications
The SCR-536 incorporated five vacuum tubeVacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...
s in a waterproof case. There was no power switch on the SCR-536. The operator pulled out or pushed in the antenna
Antenna (radio)
An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...
on the top 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 pound
Pound (mass)
The pound or pound-mass is a unit of mass used in the Imperial, United States customary and other systems of measurement...
s with batteries and 3.85 lb without batteries (2.3 and 1.75 kg). The unit operated in AM
Amplitude modulation
Amplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...
voice mode between 3.5 and 6.0 MHz 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 telescoping rod that slid into the case. The SCR-536 had an RF
Radio frequency
Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...
output power of 360 milliwatts. The range of the unit varied with terrain; from a few hundred feet, to approximately one mile over land, and 3 miles over water.
Under the Army Nomenclature System, the BC-611 transceiver was the core component of the SCR-536 Signal Corps Radio
Signal Corps Radio
Signal 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....
set. The Signal Corps technical manual number was TM 11-235.
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...
- AN/PRC-6AN/PRC-6The AN/PRC-6 is a walkie-talkie used by the U.S. military in the late Korean War era through the Vietnam War. Raytheon developed the RT-196/PRC-6 following World War II as a replacement for the SCR-536 "handy-talkie". The AN/PRC-6 operates using wide-band FM on a single crystal controlled frequency...
, post WW-II successor to the SCR-536. - 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...
- Collins Radio
- 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-299SCR-299The SCR-299 was a U.S. Signal Corps mobile military communications unit used during World War II.-History:The SCR-299 replaced SCR-197 and SCR-597, and was an effort to give a long-range communication advantage to the U.S. Army and its allies...
- 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....
- 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 :...
- Vintage amateur radioVintage amateur radioVintage amateur radio is a subset of the amateur radio hobby, considered a form of nostalgia much like antique car collecting, where enthusiasts collect, restore, preserve, build, and operate amateur radio equipment from bygone years, most notably those using vacuum tube technology.Popular modes of...
- SCR-694SCR-694The SCR-694 was a portable two way radio set used by the U.S. military during World War II. -History:The SCR-694 replaced the SCR-284 and was later replaced by the AN/GRC-9...