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- American Personal Communications,
from Walkie Talkie to Cell Phone
- By Tom Farley
"Now, for good or evil, comes
the Walkie-Talkie for civilians. Just radio, 'Bring home an extra
lamb chop,' or, "I want to report a strange man -' You can
keep quiet, if you wish - but you probably won't."
From "Phone Me By Air"
The Saturday Evening Post, 1945
This vision of a talkative wireless future appeared a half century
ago; it foresaw the hand-held devices we use today and revealed
the important link between military and civilian communications.
The war effort developed portable radios, units no longer restricted
to a car, truck, or tank. Unlike in previous wars, the foot soldier
could now carry a radio with him, communicating with headquarters,
squad leaders, or other soldiers while moving about. The personal
radio had arrived and it has never left.
Before World War II most radio transmitters and receivers
were big, bulky, and extremely heavy. Each piece could weigh
15 kilograms or more. They were so heavy that equipment collectors
call these old radios 'boat anchors.' The first step to make
a radio truly portable was to reduce size and weight. The Galvin
Manufacturing Company, now Motorola, combined a receiver and
transmitter into a single hand-held unit. They called it the
Handie-Talkie. Weighing 2.3-kg, the Handie-Talkie had a range
of 1.6 to 4.8 kilometers. This miniature marvel used five small
vacuum tubes and put out one third of a watt. Motorola made 130,000
hand held units between 1941 and 1945. The SCR-536 was typical.
Pulling out the antenna turned the radio on, pushing the antenna
back in turned it off. While the 1943 Handie-Talkie somewhat
resembles a large radio-telephone of today, it was Motorola's
backpack model, the Walkie-Talkie, that heralded a new era in
personal, portable communications.
The SCR-536. Walkie talkie
photograph originally from here: http://www.gordon.army.mil/museum/AMC/talk.htm
(link now dead)
The biggest change in radio from previous wars was personal
communications, but the most significant wartime accomplishment
for portability itself was frequency modulation or F.M. Reducing
radio size was essential, but the transistor would be invented
in a few years, making all electronics smaller. F.M. instead
was the key development and many modern two-way radios and older
cellular telephones use this technology today. As did Motorola's
1943 Walkie-Talkie. Known as the SCR-300, it weighed almost 16
kg. and had an average range of 16 to 32 km. It used 18 fragile
glass tubes. Motorola chief scientist Daniel E. Noble designed
it for the U.S. Army Signal Corps, which in turn deployed it
to the different divisions of the armed forces. These early Handie-Talkies
used conventional A.M. or amplitude modulation technology because
F.M. was newer and field radios had not used it before. But,
delayed as it was for hand-held radios during the War, larger
F.M. sets were rushed into production and used throughout the
U.S. military, a great many installed in tanks. Why F.M.?
Frequency modulation,
whereby the carrier wave is varied not by strength, as in A.M.,
but in proportion or frequency to the amplitude of the information
signal.
Interference from other radio signals, man-made electrical
noise, and atmospheric disturbances, plague A.M. radios, problems
amplitude modulation transmitters use high power to overcome.
F.M radios use less power to transmit since they're not affected
by this interference. That means lower power to operate which
means longer battery life. Transmissions sound cleaner and arrives
without static. F.M. also has a capture effect, whereby the receiver
locks on to the strongest signal it picks up, eliminating fading
and competing radio signals. After the war the military continued
working with F.M. for Handie-Talkies, producing the F.M. based
PRC-6 in 1950, now considered the first truly successful hand-held
military radio. But I am getting ahead of our story.
Amateur radio operator
circa 1950. Technical radio knowledge and Morse code ability
required for operator license. Beer served on platter and tie
wearing required for style. Click
here for a bigger picture.
In 1945 World War II ended and American civilian radio and
telephone development resumed. After showing the utility of personal
communications on the battlefield, Handie-Talkies and Walkie-Talkies
could now be developed for civillian use. Before World War II
Americans could not talk freely over the radio. You needed a
federally issued amateur radio license first, based upon passing
a test, which required technical knowledge and a proficiency
in Morse code. With these impediments only dedicated enthusiasts
pursued radio. After the war the United States re-thought civilian
communication. Why not designate frequencies for personal, non-licensed
use?
Calling for help on a
military walkie talkie converted to use civilian frequencies.
No connection to the landline telephone network.
In late 1945 the United States Federal Communications Commission
unveiled a radio plan called the Citizens Band for private individuals
and small businesses; a set of radio frequencies ordinary people
could use to communicate. No connection to the telephone network
was permitted or imagined, just people talking directly to each
other using wireless. Like Walkie-Talkie users today. Only a
simple operating license would be required, however, rules to
certify the radio equipment itself took years to develop and
were strict. Starting a bad tradition, the bureaucratic F.C.C.
took four years to fully implement Citizens Band radio, and then
few companies bothered to make radios under the strict rules
for the new equipment. By 1952 only 1,401 people had Citizens
Band operating licenses, most using converted A.M. military Handie-Talkies.
This brings us to an important point: a major factor limiting
American radio development has not always been technology but
often the policies and delays of the F.C.C.
General Radio Telephone
Company MC-5 22 channel Citizens band radio. Used tubes. Old,
heavy radios are called boat anchors.
The United States Congress created the Federal Communications
Commission in 1934 to regulate telephones, radio, and television.
It was part of President Roosevelt's "New Deal" plan
to bring America out of the Great Depression. Not content to
merely follow congressional dictates, and unfortunately for wireless
users, the agency first thought it should promote social change
through what it did. To promote the greater good with radio,
the F.C.C. gave priority to emergency services, broadcasters,
government agencies, utility companies, and other groups it thought
served the most people while using the least radio spectrum.
This meant few channels for radio-telephones since a single wireless
call uses the same bandwidth as an F.M. radio broadcast station.
Spectrum at high frequencies contained a great deal of usable
space, but the F.C.C. did not approve such large frequency allocations
for telephony until the 1970s.
Treating radio like a public utility, something like the railroads,
it was thought a public agency could protect the public against
monopoly practices and price gouging. But like many bureaucracies,
at every opportunity the FCC tried to enlarge its role and power,
eventually aligning itself with large communications companies
and then actually working against the consumer. The worst examples
were outside of telephony, helping the RCA corporation against
F.M. broadcasting, ruining Edwin Armstrong in the process, and
favoring RCA over Farnsworth, the first real developer of television,
leaving him penniless as well. Along the way were maddening delays
in approving technical advances and frequency allocations, something
that continues to this day.
Police departments across
the country quickly converted to F.M. after WWII.
Click here for a larger picture. Warning! -- this is a BIG file
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