SCR-194 / SCR-195 Radio
The SCR-194 and SCR-195 were developed by the U.S. Army Signal Corps Engineering Laboratories at Fort Monmouth, NJ, the first "walkie talkie" portable AM radios. They were fielded in 1938-39 and used widely by the U.S. and Allies during World War II, generally for batallion and company level links. The SCR-194/195 was replaced by the SCR-300 or SCR-536 in infantry and airborne units, and by the SCR-609/610 in artillery units. Although declared obsolete mid-1944, there were still many in service at that time.
SCR-194 / SCR-195 "walkie talkie" field radio. Photo: Popular Science, August 1941.
Today in WW II: 23 Sep 1940 After just seven weeks of development, American Bantam delivers the first prototype jeep to Camp Holabird, MD.
SCR-194 / SCR-195 Walkie Talkie Radio Description
SCR-195 consisting of BC-322 with accessories. Photo: Courtesy of Thomas Chial.
The SCR-194 and SCR-195 two-tube AM radio sets were nearly identical with differences in frequency band and headset/handset to meet the needs of Artillery and Infantry respectively:
||HS-22, Microphone T-24
||Handset TS-11, Remote Control RM-14
The other characteristics of the radio sets were the same:
||Metal, black wrinkle finish
||5.5 x 7.9 x 8.7 inch (140 x 200 x 220 mm)
SCR-195 with antenna fully extended. Photo: Popular Science, August 1941.
Other related equipment includes the canvas carrying bag/backpack (BG-71), leather saddlebags (BG-82) for horse cavalry, and a chest for spares. The power source is battery BA-32 and the two tubes are VT 33 and VT 67. The Technical Manual TM 11-238 describes both the SCR-194 and SCR-195.
Operating the SCR-194 and SCR-195 Radios
SCR-195 consisting of BC-322 with accessories, in BG-71 canvas carrier. Photo: Courtesy of Thomas Chial.
The SCR-194 / SCR-195 transmitter and receiver are for voice communication only. This radio set is designed for point to point communication with a range of approximately 5 miles. (In the jungles of Guadalcanal, range was reported to be much less, one to two miles.) Although the set is not equipped for code communication, code may be whistled into the microphone under conditions where interference prevents clear reception of voice.
The radio set may be worn on the back of the operator and operated from this position. Carrying straps are provided which fit over the shoulders and allow free use of hands while the set is in operation. This radio may also be mounted and operated in a vehicle. For satisfactory performance, the ignition should be shielded and the vehicular antenna used. The standard antenna should not be used for vehicular operation. The vehicular antenna (Mast sections, MS 49, MS 50, MS 51, and mast base, MP 22) is designed, electrically and mechanically, for use in a vehicle and should be so used.
There are 62 channels for communication on the SCR 194/195, each separated from the next by 400 kilocycles. Before going into the field each unit is assigned one of these channels on which to work. There are two coils in the set, marked A and B respectively. Only one is to be used at any one time. When operating on channels 1-25, inclusive, use Coil A. When operating on channels 26-62, inclusive, use Coil B. When using Coil A, the antenna is completely extended. When using Coil B, the top two sections are dropped.
To operate, place the set on the ground, and plug in the headset, microphone or handset. Check to see that the proper coil (A or B) is in place. Extend the antenna to the length corresponding to the coil being used. Screw the antenna into the top of the lid of the radio set. Turn the filament toggle switch on, and turn the filament knob until you see whether or not you can get at least 2 1/2 volts reading on the meter. If you cannot get this voltage, the battery should be replaced. After getting satisfactory filament voltage, turn the filament knob back to 2 volts, then calibrate the set. After set is calibrated, switch back to assigned channel. Cut off calibrator switch. The set is now ready to operate.
To calibrate, turn the calibrator switch on. Turn channel dial to red mark nearest the assigned frequency. A hissing sound should be heard. Adjust calibrator knob until this sound has stopped, or it is at a minimum. Set is calibrated. Turn off calibrator switch and turn dial to assigned channel.
BC-322 dataplate, partially obscured by equipment web strap. Photo: Courtesy of Thomas Chial.
Note on terminology: The SCR-536 was originally called the "Handie-Talkie" (meaning it could be carried in your hand) while the term "Walkie-Talkie" referred to man-portable backpack units like the SCR-194 / SCR-195 (meaning you could walk and talk). Gradually "walkie talkie" came to mean any small, handheld radio, including the SCR-536, usage that is not consistent with the WW II era usage.
Find More Information on the Internet
There are many fine websites that have additional information on this
topic, too many to list here and too many to keep up with as they come and go.
Use this Google web search form to get an up to date report of what's out there.
For good results, try entering this: scr194 OR scr195. Then click the Search button.