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May 1945 Radio-Craft[Table of Contents]
People old and young enjoy waxing nostalgic about and learning some of the history of early electronics. Radio-Craft was published from 1929 through 1953. All copyrights are hereby acknowledged. See all articles from Radio-Craft.
For the last two centuries our wars have been fought to secure freedom from oppressive regimes, either for our own citizens or for citizens of allied countries requesting our assistance. In the entire history of the United States, no land has ever been claimed during or after the conclusion of the conflicts. Although the human cost has been tragic - especially for those who have lost family members or suffered injuries - one undeniable benefit has been the advancement of technology. "Necessity," it has been said, "is the mother of invention." World War II resulted in significant advances in wireless communications, and the civilian radio industry was quick to exploit the new devices and methods. Futurists wasted no time prognosticating about how the postwar technology world would shape up, and of course radio figured significantly into the vision. This 1945 article from Radio-Craft is an early example.
Microwave Transmitter-Receivers Will Invade Our Private Lives
By S. R. Winters
The postwar mother has her master unit right beside her in the kitchen, thus keeping watch over children in the nursery and communicating with others at camp or husband in the fields.
When the dogs of war have been quelled, swords may not be converted to plowshares but the "walkie-talkie" and "handie-talkie," as symbols of compact combination radio transmitters and receivers, will switch to peace-time uses with the ease of flipping a coin. These vest-pocket editions of radio will have applications too numerous to be computed, too flexible to be defined.
On the basis of recent hearings (extending over a period of weeks) before the Federal Communications Commission there is a 200-page report, amassed by 231 radio technicians - a forecast of things to come in radio and electronics. Dryly labeled "Docket No. 6651," it may become as famous for its implications upon the radio structure of the future as was infamous the "little black bag" in the Government's Teapot Dome oil scandal. This bulging, brown radio volume is a blueprint of tomorrow's radio. Not only has the Federal Communications Commission turned prophet, with an unbridled imagination, but within a single volume it has pieced together, in jigsaw puzzle fashion, a compendium of radio's varied services, such as: citizen radio communication service, theatre television, centercasting, general mobile radio service, facsimile broadcast service, motion picture radio stations, geophysical service, or radio prospecting, radio for electric, gas, water and steam utilities, police radio service, limited private radio-telephone service, taxicab radio service, and bus, railroad and highway radio services.
Radio For the Citizens
Of these allocations of frequencies to various categories of non-governmental services, in the spectrum from 10 to 30,000,000 kilocycles, there is none so new and none so challenging to the imagination as the projected "Citizens Radiocommunication Service." Without the usual demands for frequency assignments in an already overcrowded spectrum, the Federal Communications Commission did the startling thing of voluntarily allocating the band from 460 to 470 megacycles to a multitude of private uses of radio, just over the post-war horizon. It was a generous gesture of recognition of "walkie-talkie's" war contribution. This government move was as if to say to all light-weight, portable, short-range types of radio, "You have performed admirably on the battlefronts - now the doors swing wide for peace-time opportunity of performance." Instead of the proverbial sky or Heaviside layer being the limit, the Commission asserts that the possible uses of low-power, portable transceivers are as broad as the imagination of the public itself, and its adaptation is circumscribed only by the ingenuity of radio manufacturers in devising equipment to meet the varied applications.
The vision of a Jules Verne or a Hugo Gernsback alone could match the Federal Communications Commission in lifting the veil of the future - forecasting the startling civilian uses of the war's walkie-talkie, the airplane pilot's throat microphone and the vest radio with wrist microphone, earphones under cap, and transmitter in special pockets. Not visionary, but just over the horizon of actual accomplishment, the war-converted walkie-talkie will contact a physician from a central exchange while he is en route by automobile to a patient's home; the farmer's wife who formerly summoned her husband to the noon-day meal with a clanging dinner bell will call him on 460 megacycles; hunters exploring the far reaches of forests or swamps, in search of wild game and fish, will be in contact by radio with a central hunting and fishing lodge; department stores, dairies, laundries and similar business concerns will communicate directly by radio with their delivery trucks en route; city firemen will employ the throat microphone, now used by aviation pilots in detecting speech by the quivering of the throat; and cowboys on our western plains will carry vest-pocket editions of radios to communicate with home or ranch.
It is doubtful whether this is within the scope of Citizens' Radio or will need a commercial license. In any case, radio will be widely used for office-mobile unit communications.
Common carrier operation in the citizens' radiocommunication channel of frequencies will not be permitted by the Commission; no fee can be charged for the sending of messages and no charge made for the use of licensed facilities. Thus the service will be for the private use of the person licensed and he will be governed by the regulations of the Communications Commission. The 460-470 band allocated to the public is said to be admirably adapted to short range communication, requiring only feeble power. However, the government rules are sufficiently flexible to allow the use of "booster" or automatic relays. The low-power transmitters will not utilize extremely high antennas, but increased transmitting power wil be permissible in remote rural areas, where interference is absent.
Flexible, too, is the design of the combination transmitter and receiver, although its weight will be kept to a minimum and preferably mounted in a suitcase. A broadcast receiving unit, an alarm outfit, or a remote control system may be incorporated with the transmitter in the suitcase, variable as the particular needs may dictate. Following the policy of the service to radio amateurs, the Commission will not assign individual channels within the allotted band. The use of simple circuits, already known to the radio art, will mean that both transmitters and receivers will be tunable over most of the 460-470-megacycle range - emitting sufficiently sharp signals to prevent any possible interference.
This new public radio service is designed to serve the greatest possible number of users, hampered by only a few requirements of the Communications Act, and a minimum of traffic rules need be imposed, No technical knowledge is required to participate in the "Citizens Radiocommunications Service," and the operator's license takes the simple form of a small card, remaining in force for a five-year period. The particular licensees are not cloaked with immunity from interference; they have no vestment in any frequency or channel - instead, it is a mutual opportunity to share this new band with others. Radio technicians assume that the 10,000 kilocycle width of the band is ample for its purpose.
"Votes by Radio" Turned Down
As a parallel to the Crosley and other popular polls by sampling the opinions of select individuals, the so-called "Centercasting" (See "Votes by Radio," Radio-Craft, March, 1945) as "a means of radio voting or polling" was refused the requested assignment for radio frequencies. Nonetheless novel as an offshoot of radio developments in the immediate post-war period, the system and instruments involve the use of a graphic recording device, named the "audimeter. It is at present installed in home radio receiving sets, supposedly representing a cross-section of homes, determined by a sampling procedure based on data obtainable from the Bureau of Census of the U. S. Department of Commerce. The listening record appears on a continuously moving wax-coated tape, indicating with precision the day, hour, and minute that a particular radio receiver was switched on, each and all stations intercepted, the number of minutes of listening to each station, the amount of dial twisting, and just when the receiver was turned off. Possessing such data, the company sponsoring "Centercasting" is able to determine the number of minutes listened to each program. Currently, this service has been sold to 40 clients, including the broadcasting networks, commercial advertisers, and advertising agents.
Realizing that radio affords the only speedy avenue of communication for the operation and control of fire-fighting equipment in going to or from a conflagration, the Federal Communications Commission has tentatively assigned 15 radio channels for governing the movement of trucks and other mobile units, as well as firemen, while the latter are working in burning buildings or areas. A home fire is burning somewhere in this country everyone and one-half minutes and, startlingly enough, a fire fans out to 50 times from its incipient stage within eight minutes. Thus, it is significant that 92 cities with populations exceeding 100,000, and 890 cities with populations ranging between 10,000 and 100,000 persons, have indicated to the Federal Communications Commission their intentions to adopt radio as an agency to combat fires. In addition to the fixed radio stations required in each of these municipalities, it is estimated that 128,000 mobile fire department units will be equipped with radio equipment soon after the cessation of hostilities.
The FCC has issued permits for the operation of eight fixed radio stations, and 175 portable and portable-mobile stations by transportation companies. These stations are in operation in Chicago, Cleveland, Detroit, Fort Wayne, Philadelphia, St. Louis, Seattle, Washington, Columbus, Spokane, Pittsburgh, Boston and New York City. Stations in Chicago, Cleveland, Detroit, New York, Philadelphia, St. Louis and Boston are employed exclusively in connection with transit operations in the respective cities; in the other cities mentioned above, the radio stations are used jointly with local power companies. Twenty other transit companies have indicated their intentions of building radio stations as soon as the equipment is available.
For Highway Maintenance
By their very numbers, Citizen Radios will make reliable communication possible in time of emergency or disaster.
A "Motion Picture Station" is operated as an intermittent service. It functions for communication purposes in conjunction with the filming of moving pictures. Studios employ radiotelephone signals between headquarters in Hollywood and film colonies on remote locations, aboard ships, or in isolated, rugged areas. Infrequently, radio may be used by motion picture concerns as an agency to conserve life and property, when the invisible waves are the only medium of communication between studios and locations far removed from what we of the city call civilization.
With the stringency of gasoline rationing unrelaxed, the proposal to use radio in dispatching Cleveland's 430 taxicabs augurs. a trend rather than accents an example. These cabs are now being dispatched by wire lines, but by way of the ether the driver, immediately preceding the discharge of a passenger, would report to headquarters his cab number and the location at which he was or would be available. His car would then remain at the designated location until otherwise instructed by radio. In this manner, taxicab "cruising" would be sharply curtailed and the ordinary mileage of Cleveland's 430 taxicabs reduced from 4,000,000 to 3,000,000 miles.
Electronics, just a continuing process in the unfolding of the broad aspects of radio, also will afford limitless vistas in the post-war world. Tiny electronic devices will avert automobile and airplane collisions; traffic signals within motor cars and planes will glow as red and green warning signals. Even the dashboard instruments will function electronically; electric eyes will automatically turn on auto headlights as darkness blankets the arteries of commerce; tourists traveling from New York City to California will transfer the responsibility of guiding the steering wheel over to a photoelectric cell which will scan a white line on the highway - and follow it unerringly. Such are the vistas of radio and electronics - just beyond the horizon - when the fierce dogs of war bark no longer.
Posted December 29, 2014