SCR-536 Handie-Talkie Radio Set
The events of World War II placed America's armed forces in combat across the globe. Our fighting forces needed lightweight, reliable radios. Among the most innovative solutions was the SCR-536 family of radios, the world's first self-contained, hand-held radio specifically designed for ground troops.
With its primary mission of amphibious assault against heavily-defended enemy islands, the Marine Corps required radio sets that were simple and rugged under the most demanding conditions. Unfortunately, the state of 1940s technology was such that it was sometimes impossible for radios to meet the need.
Until just before World War II, the Marine Corps radio sets were supplied under contract to the US Navy by various manufacturers. In 1941, the Marine Corps began to purchase radios on contract through the US Army Signal Corps. Among the sets purchased under these contracts was the SCR-536.
The Army Signal Corps procured the first SCR-536 radios in 1940. These were built by Galvin Manufacturing, which changed its name to to the more familiar Motorola in 1943. Between 1940-1945, Motorola build more than 130,000 of these sets. There were six different models, identified by the suffix letter 'A' through 'F' following the number '536'. The various modifications all functioned identically. The letters "SCR' stood for 'Signal Corps Radio.'
During the war, this radio set was often called the Handie-Talkie. It has sometimes been identified as the Walkie-Talkie by collectors and militaria enthusiasts, but this term actually belonged to the SCR-300 backpack radio.
Characteristics of the SCR-536 Radio
|Weight (complete): 5.5 pounds
Power supply: 2 batteries(1 BA-37 & 1 BA-38)
Frequency: AM 3,500 to 6,000 kilocycles
Range: 100 yards to 1 mile
Battery life: 15 hours
||Nomenclature of the SCR-536 as depicted in TM 11-235. US Army illustration
This radio was capable of functioning on any channel within the above bands. However, each set could only operate on one channel at any one time. The radioman could not change frequencies, as this was preset at the factory, or by maintenance personnel at authorized repair points. Technical Manual 11-235 offered the following description:
"Radio set SCR-536...is designed for short-range two-way voice conversation...[I]t is a press-to-talk portable radio telephone, receiving and transmitting on the same frequency. No skill is required to operate it. The set is self-contained; all equipment necessary for reception and transmission is contained in one aluminum case. The set may be held in either hand when operating, although it is designed and balanced for left-hand operation. The microphone and earphone are attached to the case in such a manner that the set resembles and hand telephone. An adjustable carrying strap is attached to the case."
||Operation of the SCR-536 as depicted in TM 11-235. To turn the radio on, the radioman unscrewed the antenna cover, and then extended the antenna fully. To turn the set off, he collapsed the antenna. US Army illustration
Among the very first Marine Corps units equipped with the SCR-536 was the 2nd Raider Battalion, which used the new sets in combat on Guadalcanal with good results. By early 1944, the SCR-536 was in general service in the Fleet Marine Force. It was primarily intended for use within the rifle platoon and company.
As a communications tool between platoon leaders and company commanders, the SCR-536 was an innovative tool, but it was not a perfect solution by any means. There were many obstacles that hindered the ability to stay in contact using this set. Under good weather conditions with a clear line-of-sight, this radio usually functioned well. But its range was sometimes severely impacted by inclement weather, heavy vegetation, and other environmental factors. One of the most severe shortcomings of the handie-talkie was that it was not compatible with FM radios. Although it could operate on some of the frequencies of the TBY and TBX radio sets, the 536 did not use the same bands as the SCR-300 Walkie-Talkie radio.
In the novel Battle Cry, World War II Marine Leon Uris portrayed the use of the SCR-536 during a battalion hike by the 2nd Battalion, Sixth Marines, in New Zealand:
"At least we got one break. We wouldn't have to hike with ass packs. We had received a shipment of Army SCR [handie-]talkies. They were little hand sets weighing just a few pounds, set to one channel. They were perfect for communications on the march—if they worked. We packed the TBY's in the comm cart, just in case."
But as Uris continued the story, a short while later it began to rain heavily, and the SCR's stopped working. The radiomen had to break out their heavy TBY radios, and stow the handie-talkies in the hand cart. The next day, the little radios started working again once the weather cleared up.
||A Marine uses the SCR-536 during one of the Central Pacific campaigns in 1944. By this point in the war, the 536 was the standard radio within the Marine rifle company. USMC Photo
In 1944, The Marine Corps Gazette made the following observation regarding the SCR-536:
"The use of ultraportable radios in the jungle is restricted; their effectiveness depends to a great extent on their location. Dense undergrowth and precipitous slopes have a screening effect."
In an article for The Marine Corps Gazette in 1945, Marine 1stLt Robert W. Fisher analyzed the SCR-536 in the Okinawa campaign:
"The diminutive SCR-536, better known as the Spam Can, was used extensively by companies and platoons, but did not prove durable enough."
2ndLt Craig Leman, USMCR
Craig Leman, a retired surgeon who lives in Corvallis, Oregon, served as a platoon leader in 1st Platoon, Company H, 2nd Battalion, 26th Marines, during the campaign for Iwo Jima. I sent him a message asking if he remembered using the handie-talkie in combat. He replied to me in a story that does much more than just relate technical data about a radio:
"Hi Mark. I certainly do!!!!!!!!!!!!!!!!! I never saw one nor heard of one until D plus 10 on Iwo when I joined H Company, which was then in reserve, as a replacement platoon leader. I don't remember whether it was [the platoon sergeant, Cpl] Nick Hernandez or a runner from Company headquarters who gave it to me, as the new leader of first platoon, and showed me how to use it. It was hand-held, with a two-way switch to send and receive. As I recall (and it is 65 years since I used the device), I had to press on the switch to send, giving my message to Company headquarters, saying "over." Our company's title was "How 6" and my platoon's was "How 1." We used no codes and trusted that the Japanese were not listening in.
On the fourth night at about 0200, I got word via the field telephone that we were to make a surprise attack at dawn with no pre-attack bombardment. We were under strict orders not to leave our foxholes during the night and to shoot anybody who was observed moving around in our area assuming it would be an enemy infiltrator. However, we had to be silent, as the Japanese were within easy earshot. It seemed essential that every man in the platoon receive the word that we were going to move out at 5 AM.
As a green officer new to the unit, I was not sure how to resolve the dilemma of how to pass the word. In the light of a flare, I saw our flamethrower[man,] Pfc Don Simpson, on watch in the next foxhole, and beckoned to him. He ran right over, jumped into my foxhole, volunteered to deliver the message personally to everyone in the platoon, and did so himself. Just another example of how an experienced [Marine] helped educate a green lieutenant.
We moved out at first light on signal from How 6. I carried the handie-talkie. We moved carefully up into the ridge-country ahead of us. One man in our platoon saw a Japanese sentry sitting apparently asleep at a cave entrance, and shot him. Immediately, many Japanese soldiers ran out of two entrances (about a hundred feet apart) of the cave, and engaged us in a furious fire and grenade fight.
[Cpl Hernandez] joined [Pfc Eugene] Frost's squad at one entrance, and I joined [Pfc Frederick] Sisk's at the other entrance, and ran back and forth between the two, carrying my M-1 in one hand and the handie-talkie in the other. [Capt Donald] Castle, the Company Commander, was on the other end, back in the Command Post. I had trouble coping with the button system and remembering to turn it on and off as I tried to figure out what to do with the hornet's nest we had stirred up, but I managed to keep [the CO] semi-posted, to accept his offer of a half-track to support our efforts, and to have him send up stretcher parties for our wounded.
When the cave blew up, I was practically buried, and the rocks coming down bent the aerial of my handie-talkie, which I protected with my body, though the aerial stuck out. However, it worked, and I was able to tell him to send up all the stretcher-bearers he could find to dig us out. At the end of this scrap, my platoon was down to [eight Marines], so we were combined with third platoon and advanced about 500 yards through level open terrain, killing a couple of Japs in foxholes, left behind to slow us up, and then moved into rough country and heavy fire. The handie-talkie was no problem at that time. I don't remember whether we used it or the field telephone that night or next day.
We were ordered to make a daylight attack on 8 March 1945 in rough terrain from our position at the base of a rocky cliff where we had been stopped the night before by heavy rifle and machine gun fire from concealed positions. We had lost Sisk [who later died of his wounds] and another Marine who were shot at close quarters while they were putting our concertina wire in front of our lines. The Japanese positions were well concealed, and we were pinned down and unable to mount an attack. I asked for tanks, and Castle said that they could not negotiate the terrain. He sent down an armored bulldozer to make a road for them, but the two engineers who were moving rocks from in front of it were promptly shot, and the dozer left.
I told Castle that we were pinned down and unable to move. He replied that we had to, because the whole division was attacking and that we had to keep up pressure, so that, if one outfit made progress, its flanks would be vulnerable, and they were counting on us to keep the pressure on. Nick had just been killed. I told the squad leaders we had to keep trying. They said it was impossible. I told them that I would go first and they should follow me. They agreed. I did not carry my handie-talkie. I did carry my M-1. (I carried an M-1 for two reasons; first, it was a much better weapon than my carbine, more fire-power and less likely to jam, second, it gave me the same odds as my men, instead of stamping me as an officer, for special attention by the enemy.) I was shot almost immediately, and we spent the rest of the day shooting back at them from our foxholes.
In retrospect, I feel that the handie-talkie was useful, a real advance over field telephones in reliability and mobility. It was not very user-friendly; fairly heavy, clumsy, a magnet for enemy fire at close quarters combat. It was almost impossible to be an effective combatant while toting this brick-like object with an aerial. It was classic intermediate technology, and I hope that the Big Brass have employed the technological advances of electronics, miniaturization, and, in particular, education and drills for the users in preparation for the modern battlefield."
Although it had several shortcomings that were never remedied completely during the war, the SCR-536 filled a unique role. Under most conditions, it allowed small units to stay in contact when they otherwise would have been forced to rely on wire or messenger. The handie-talkie was the first truly compact tactical radio. The 536 was used in the US armed forces through the 1950's and was eventually replaced by the AN/PRC-6 lightweight radio.
||A Marine uses the SCR-536 during the campaign for Iwo Jima. USMC Photo
||Date plate from an SCR-536 manufactured in 1944. The designation BC-611 identified the inner components of the radio set. WW2 Gyrene collection
WEAPONS AND EQUIPMENT INDEX
WORLD WAR II GYRENE HOME
Technical Manual 11-235, Radio Sets SCR-536-A, SCR-536-B, and SCR-536-C, War Department, May 1943.
Anonymous (September 1944) Jungle Warfare, Marine Corps Gazette.
Fisher, Robert, (December 1945) Communications For Small Units, Marine Corps Gazette.
Uris, Leon, Battle Cry, G. P. Putnam's Sons, 1953.