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- American Personal Communications,
from Walkie Talkie to Cell Phone
- By Tom Farley
On June 17, 1946 in Saint Louis, Missouri, AT&T and Southwestern
Bell introduced the first American commercial mobile radio-telephone
service to private customers. Mobiles used newly issued vehicle
radio-telephone licenses granted to Southwestern Bell by the
F.C.C. Mobiles operated on six channels in the 150 MHz band.
Bad cross channel interference, something like cross talk on
a normal telephone line, soon forced the Bell System to use only
three channels. No more than 25 people at once could use the
system. Operators placed calls for each customer. Despite high
costs and constant busy signals, waiting lists developed in every
city where radio-telephone service was offered. The chief problem
was that the F.C.C. would not make enough channels available
for a high capacity mobile telephone system. Still, technology
and planning moves on, even if bureaucracies do not.
What might have made
up an early mobile telephone; equipment is actually unrelated.
"A" is the control head, the mechanism placed inside
the cab which controls volume and channel selection. "B"
is the microphone, no telephone handset or keypad used. "C"
is the actual radio gear, the transceiver, which gets built into
the trunk. Massive size, weight and bulk. Click
here for closeups and see the footnote
for a detailed description.
In December 1947 Bell Lab scientists circulated a paper amongst
themselves describing a prototype cellular system. It would overcome
every limitation of the present mobile telephone service. They
now knew everything needed for cellular radio, but it would take
hundreds of new frequencies, a digital telephone switch, microprocessors,
and digital signal processing circuitry to make this dream a
reality. One major step toward completing that dream occurred
the next year.
On July 1, 1948 AT&T unveiled the transistor, a joint
invention of Bell Laboratories scientists William Shockley, John
Bardeen, and Walter Brattain. It would revolutionize every aspect
of the telephone industry and all of communications. Some say
that it was the greatest invention of the 20th century. One engineer
remarked, "Asking us to predict what transistors will do
is like asking the man who first put wheels on an ox cart to
foresee the automobile, the wristwatch, or the high speed generator."
The transistor would dependably amplify and switch signals while
producing little heat. Equipment size would be reduced and reliability
increased. Hearing aids, radios, phonographs, computers, electronic
telephone switching equipment, satellites, and moon rockets would
all be improved or made possible because of the transistor.
My writing on the transistor / Michael
Riordan's writing on the transistor
The first transistor
looking as crude, perhaps, as the first
telephone. Click
here for a slightly larger photo.
Fostering world wide transistor development was a relaxed
patent policy by AT&T. Fearing an anti-monopoly lawsuit by
the U.S. States Justice department, the Bell System allowed anyone
for $25,000 to use its transistor patents. Starting then in the
late 1940s, and continuing for twenty years, radio engineers
around the world replaced fragile, bulky, high current vacuum
tubes with rugged, miniature, low powered transistor circuits.
It was not until the mid 1960s that most electronics eliminated
tubes and become all solid state. Still, radio advanced in other
ways throughout this period.
In 1950 the PRC-6 Handie-Talkie debuted as a replacement to
the badly aging World War II Handie-Talkie. The military's first
F.M. hand-held radio, the PRC-6 weighed less than its older brother,
used less power, and contained fewer tubes. Few saw actual service
in the Korean War, with most battlefield communications using
World War II equipment. Then, in 1951 an improved backpack or
Walkie-Talkie also began production. The PRC-10 had a range of
three to five kilometers. Again, owing to limited numbers being
made, few were actually deployed to Korea.

The handheld PRC-6 on
the left and the backpack PRC-10 (without the backpack that normally
contains it) on the right. Photos are from this great radio resource:
http://www.armyradio.co.uk (external link), the place to buy
used military radio gear.
On January 31, 1954 a 64 year old man wrote a letter to his
wife, dressed for work, and walked out of his 13th floor apartment
window, plunging to his death. Colonel Edwin Armstrong, the father
of modern radio, and the creator of the first F.M. system, had
committed suicide. A brilliant but sensitive man, Armstrong allowed
the U.S. military to use his patents royalty-free for the duration
of World War II. Before that he played a crucial role in communications
during the First World War. He pioneered vacuum tube technology,
making it practical, and invented radio circuits that transformed
the entire communications industry.
Armstrong rightly believed that F.M. was a revolutionary operating
system and that it should replace A.M. equipment for broadcasting.
Indeed, no technical reason exists for A.M. broadcasting to continue.
A.M., with its static, high power requirements, and fading, continues
only because of tradition, bureaucracy, and sloth. Tired and
despondent after fighting one patent lawsuit after another against
industry giants like RCA, his personal fortune spent on promoting
and defending F.M., Armstrong finally gave up and killed himself.
Every radio today has circuits Armstrong designed. 1954 also
marked happier events.
Edwin Armstrong, radio
genius.
In October, 1954 the Regency TR-1 became the world's first
commercial transistor radio, using Texas Instrument's new silicon
based transistors. Built by the little known American firm Industrial
Development Engineer Associates, but actually designed by Texas
Instruments, it was followed six months later by Japan's first
transistor radio, the Sony TR-52, an experimental set never actually
released for sale. In 1957 the Sony TR-63 came to America. These
transistor radio receivers were important milestones but both
radio-telephone and military radio used higher current to transmit
than transistors of that era could handle. Transmitting was still
a job best left for tubes and an all transistor Handie-Talkie
would have to wait.

Regency's TR-1 (1954)
on the left, and Sony's TR-63 (1957) on the right
Radio research and development increased in the late 1950s
when America entered the Space Race with the former Soviet Union.
One great achievement was the integrated
circuit by Jack Kilby of Texas Instruments in 1958. Putting
several dozen transistors on a single silicon chip quickly reduced
radio size and weight. In that same year the Bell System petitioned
the F.C.C. for more conventional radio-telephone channels. Citizens
Band had become more popular but people really wanted to communicate
by telephone. Every radio-telephone system AT&T maintained
was at capacity and there were no more frequencies to service
new customers. Worried they would give more power to the Bell
System, which had in effect a monopoly on most wired telephones
in America, The F.C.C. did not seriously consider their wireless
appeal for ten long years.
In 1962 Motorola introduced a fully transistorized two-way
radio. The Handie-Talkie HT200 weighed approximately 1 kilogram
and was known affectionately by its users as "The Brick."
Shortly thereafter, in 1965, the military got the PRR-9, the
first all solid state portable for the armed forces. This VHF
equipment received but did not transmit, it's companion, the
FM PRT-4 transmitter did that. The PRR-9 clipped onto a soldier's
helmet. I don't have a photograph of that model in action, but
check out this well dressed warrior from 1963; the principle
is the same.
By 1968 the U.S. military was using many new portables in
the Vietnam War, including tiny models called survival radios
that provided communication between downed fliers and rescue
services. The greatest change from previous wars was a decision
to make voice and data communications secure if needed, hence
all radios became encryption ready from that year on.
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Extended discussion
regarding that mobile telephone photograph
Mobile telephone expert Geoff
Fors (external link) comments on the mobile telephone photograph
on this page, and the other two images on my Seattle
Telephone Museum Page:
"With apologies to the hard working people at the Telephone
Museum, the photograph does not depict an old mobile phone, even
though it might look like it does."
"The drawer unit (electronics package) is a GE Progress
Line BE-33 or WE-33; they look the same, I think this one is
a BE. Six volt versions were BA-33 or WA-33. The "B"
means Bell System and the "W" means Western Electric.
This unit appears to be a BE-33 which is actually a "dispatch"
radio made for the Bell System maintenance trucks, and those
usually did not have a VS-1 supervisory signalling set (the little
stepper decoder). You can see the mostly empty panel inside where
the VS-1 normally sits. I have such a radio in the basement.
The WE-33 looks the same but came with a Western Electric series
47A head and a VS-1 rotary stepper decoder."
"Sometimes BE-33's were later made into mobile phones
by using a Scantlin transistorized decoder which mounted under
the car dashboard. The GE Progress Line unit in the photo dates
from 1955-58. Bell System radios were for telco maintenance trucks
and not true mobile phones. They are usually identified by the
white "Bell System" lettering on the case. Only the
WE-33 was a true mobile phone. I am not sure if WE-33 Western
Electric contract phones said Bell System on the case as well.
You would think they would have, but there were some strange
protocols at the time."
"The control head above it goes with a Motorola Twin-V
conventional two way radio of 1955-57 vintage and has nothing
to do with the GE. They are not compatible and were never used
together. The mike has nothing to do with any of the other pieces
either."
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