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Private Line covers what has occurred, is occurring, and will ocurr in telecommunications. Since communication technology constantly changes, you can expect new content posted regularly.

Consider this site an authoritative resource. Its moderators have successful careers in the telecommunications industry. Utilize the content and send comments. As a site about communicating, conversation is encouraged.


Thomas Farely

Tom has produced since 1995. He is now a freelance technology writer who contributes regularly to the site.

His knowledge of telecommunications has served, most notably, the American Heritage Invention and Technology Magazine and The History Channel.
His interview on Alexander Graham Bell will air on the History Channel the end of 2006.

Ken Schmidt

Ken is a licensed attorney who has worked in the tower industry for seven years. He has managed the development of broadcast towers nationwide and developed and built cell towers.

He has been quoted in newspapers and magazines on issues regarding cell towers and has spoke at industry and non-industry conferences on cell tower related issues.

He is recognized as an expert on cell tower leases and due diligence processes for tower acquisitions.

January 04, 2006

American Personal Communications, from Walkie Talkie to Cell Phone

"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: (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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