Transportation Deployment Casebook/Wired Telephones

By: Mark Powers

Introduction to Wired Telephones

The telephone was the first electrical instrument to transmit speech via wire. The early technology of the telephone is derived from the telegraph. Both devices use electrical pulses to transmit a signal across a wire. While Alexander Graham Bell is credited with the invention of the telephone in 1876, the matter is still debated. The telephone is superior to the telegraph in multiple ways. Firstly, the telegraph could only send the sounds of a dot and a dash while the telephone was capable of transmitting speech. Second, a telegraph was only capable of transmitting one signal at a time across a single wire, while the telephone can utilize the same wire to send multiple signals. Use of the telephone quickly became widespread across the US and the world.

The 1870's and the Race to Invent the Telephone

Use of the telegraph had become widespread and was the only communication mode of the time that could send a message across long distances in a short time. The capabilities of the telegraph was limited by its technologies, and multiple inventors sought to improve upon it. One such idea was to develop a method of transmitting speech with the use of electricity. While many are men are credited with trying to invent the telephone, the final race came down to Alexander Graham Bell and Elisha Grey. It is said that both men went to the patent office on the same day, but that Bell had beaten Grey there by an hour, and was awarded the patent. Grey attempted to sue Bell for the patent, but ultimately lost.

The Birth and Growth of the Telephone

Bell had teamed up with a young electrician named Thomas Watson. Initially they were working on an improved telegraph that would be capable of sending multiple signals across the same wire. Working with Watson, they were able to determine how different tones would result in varying electrical pulses. The first telephone message was then made on March 10, 1876 by Bell to Watson in the other room when he famously said, "Come here Mr. Watson, I want to see you." The Bell Telephone Company was founded in July 1877 and by the end of that year there were 3000 telephones in service, and 10,000 by the middle of the next year. The first telephone lines were constructed in Boston and were made of iron and steel. Not long after iron and steel was replaced by copper wiring. Phone services continued to expand, and the first switchboard was constructed in 1878 and located in New Haven Connecticut. Up to this point, all phones operated on one-wire circuits, and the sound quality was poor. To improve upon this, Bell invented a new two-wire circuit in 1881, which was also encased in lead to further cut down on noise. Also in that year, the first long distance service was opened up for calls between Boston and Salem.

The Next giant leap forward for the telephone came in 1891 in Kansas City, Missouri. An Undertaker named Almon Strowger grew irritated by constantly waiting on operators, and also feared that some operators were purposely routing his customers calls to his competitors. To get around this situation, Strowger invented the first automatic switching telephone. This was the first model that modern phones were based on in that it was capable of dialing its party directly without the need of an operator.

Expansion

In 1894 the Bell patents finally expired. This allowed other companies to jump into the fray. Independent phone companies began to appear all over the country. A lot of the areas where the independent companies came about were smaller and rural areas that didn't appeal to Bell. Bell continued to expand rapidly over the early 1900s and by 1915 completed its first coast to coast call from New York to San Francisco. Expansion continued to grow exponentially until the Great Depression hit in the 1930s. For the first time ever, phone companies saw a decline in customer base. Production picked up right where it left off after the depression had passed, and the telephone was on the verge of a major boon. The end of the 1930s also so the formation of the Federal Commerce Commission. To this day the FCC is still the regulatory agency that oversees telephone companies.

The War and the Explosion of the Telephone

While telephone service was already expanding rapidly all over the country under its own device, World War II proved to be the catalyst. During the war the demand for service was greater than the companies, who were putting the majority of their efforts in to the war, could keep up with. One innovation that came about during the war was the coaxial cable which could accommodate 600 phone calls at once. By the end of the 1940s the dismantling of Bell Telephone had begun under the new antitrust laws. The suit was finally settled in 1956, and Bell was left intact. The 1950s and 60's was a time of innovation and style for the telephone. In 1963 the touch tone phone was invented. The same combination of overtones and undertones used on these phones is still used on all modern phones. The 60's also brought unrest, as union strikes brought a halt to service for a time in New York.

The Demise of Bell and Expansion Begins to Slow

By the 1970s there were over 100 million phones in service. In 1970 the FCC ruled that independent companies, called common carriers, could begin to service businesses. Then in 1974 the US government once again attempted to dismantle Bell Systems. The trial was delayed until 1979 and finally ended in 1983, but this time it succeeded and Bell Systems was torn apart. The late 80's and 90's saw landline telephones giving way to newer technologies like cell phones, cable, and the internet. There was less and less demand for landlines.

Growth Model of the Telephone System in US

For this model data was extracted on the miles of telephone wire in the US from the United States Census Bureau records.

Figure 1 - Telephone Wire in the US and developed S-curve

Coefficients used in developing the S-curve

Analysis and Conclusion

As one might expect, it would seem that landlines are peaked in the US. The developed S-curve model has an upper asymptote of 1,650,000,000 miles. The inflection came about in 1971. As discussed earlier, the cell phone, cable television, and internet industries have replaced the landline telephone as mode of communication. It seems conceivable that at some point in the near future telephone landlines begin being removed to make way for newer infrastructure. However, this mode will likely not ever be completely erased. The reliability of the service is too good to not have around in some capacity in case of emergency.