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Part G

Michael Hathaway reports that "[My] parents owned the Bryant Pond Telephone Company in Bryant Pond, Maine, the last hand-crank magneto company to go dial. It was in our living room and the last call was made October 11, 1983." Hand crank magneto switchboards evolved around the turn of the century. Their arrangement was not common battery, where the exchange or central office powers their equipment and supplies electricity to customer's phones. Rather, as we saw earlier in this series, a crank at the switchboard operators position was turned to signal a customer. Turn the crank and you caused a dial at a customer's telephone to ring, a magneto in the crank generating the ringing current. To place a call a customer signaled the operator with a similiar crank on their telephone. A big battery in the base of the customer's telephone supplied the talking power when a call got connected. This system is called local battery, where the customer's phone supplies the power. Here's an example of a magneto switchboard below, a 1914 Western Electric Type 1200, known as a "Bull's Eye." This board is at the Roseville Telephone Company Museum and it still works for demonstrations. Click here or on the image below to see the large version.

So, you had many people on non-dial, candlestick or box telephones, as nearly a hundred years before. My father, incidentally, worked a magneto powered switchboard in his youth, near Davidson, Michigan. Mike goes on to say that,

"My father and mother Elden & Barbara Hathaway sold the Bryant Pond Telephone Company in 1981 but it took two years to convert. They did have about 400 customers ( probably 200 lines - two switchboards full). When they bought the company there were only 100 customers. The Oxford County Telephone Company, which bought it, retained ownership of the last operating switchboards, and they are currently deciding what they would like to do with them. The options include giving them to the town of Bryant Pond, and I have heard there is interest from the Smithsonian. My mother, who is 83, thinks that's quite exciting.

A lot of the family memorabilia has been donated to the Fryeburg Fair (Maine) Farm Museum, which although is only open during the 8 day fair, is visited by many thousands each year. It is hoped to have within a year or so a working magneto switchboard there where someone can call from an old pay phone to anywhere. My mother has a lot of telephone parts left over which we are slowly marketing for her as memorabilia from the last old hand-crank magneto company. I've actually written a book about the Bryant Pond Telephone Company called 'Everything Happened Around The Switchboard.' It's (obviously) a story of family life around the switchboard and is light reading with hopefully humor and nostalgia. I have lots of copies left and sell it directly. The address is Mike Hathaway, PO Box 705, Conway, NH 03818. But it is also available from Phonecoinc.com, and several bookstores."

This site has a great list of ending dates in telephonic history: http://www.sigtel.com/tel_hist_lasts.html

To sum up, although some manual switchboards may have remained in the PSTN, those being small office switches, or PBXs, the Bryant Pond board was the last central office manual exchange in America. On this happy and nostalgic note of technology passing away, so at the same time was the world's greatest telephone company coming to an end.

Although they had pioneered much of telecom, many people though the information age was growing faster than the Bell System could keep up. Many thought AT&T now stood in the way of development,

7. PART H -The Letter and Number System

Back in 1957, when I was 12 years old, I was absolutely fascinated by my city (Dayton,OH) changing over from the old 2L-4N (two letter, four number) system to the new 2L-5N system. Over 350,000 subscribers went to sleep on Nov.16th with the old system and awoke Sunday morning with the new one. My RAndolph had suddenly become CRestview 4. The conversion chart was on the back page of the new directory which I copied down and this became the humble beginning of my 50 year old hobby.

I found that the public library had many Ohio directories and at least every state capital in the US plus other larger cities and some foreign directories. Everywhere I went I always had a notebook and pen to jot down the phone prefixes. I even wrote to the telephone companies to get more details about their prefixes. For many years I thought I was the only person on the planet who was interested in stuff like this. Then I bought a computer and found that there were websites dedicated to people with similar hobbies. One such site was The EXchange Name Project to which I personally donated around 10,000 exchange names or prefix names and their respective cities from not only the US and Canada, but also the UK, France, Denmark,(all of which had names) plus Cuba, Hong Kong, and the USSR (which only used letters with no names related to the letters).

The rest of the world also became my target such as recent major conversions in Mexico, Brazil, Colombia, Bolivia, Turkey, India, Pakistan, Saudi Arabia, Switzerland, Ireland, additional 7-digit areas in the UK and so on. Of course, these places always had only numbers in their systems, but it was perhaps the fact that they were making major changes that North America had made long ago. My one regret is that there is really nowhere to go on the web to look up history (i.e. old telephone numbers with named prefixes) for some of the ones I don't have. Some itty-bitty towns such as Antler, ND where all I have is "CO7" for example. I specifically put this and others on the TENP website so that maybe somebody in North Dakota would write a comment like "Oh yeah, my grandma's number was..." Unfortunately, they must have other hobbies up there!

In summation, before I bore you to death, I realize that eventually all-number calling was the way to go, but as I recall the Ma Bell of olden days was a kinder, gentler Ma Bell who was worried that the loss of the old named prefixes would be a larger problem than it actually was. The plan for Dayton's change to all numbers was begun in 1961 and was supposed to have been completed by the new directory in 1965, but there was little opposition in Ohio, so by the time 1963 rolled around there were no mixed (letters and all-numbers) listings left. I read where this was not so easy in other areas such as Los Angeles where large groups of anti ANC people took the telephone company to court over the loss of the letters.

V.

PARTS OF A TELEPHONE

A basic telephone set contains a transmitter that transfers the caller’s voice; a receiver that amplifies sound from an incoming call; a rotary or push-button dial; a ringer or alerter; and a small assembly of electrical parts, called the antisidetone network, that keeps the caller’s voice from sounding too loud through the receiver. If it is a two-piece telephone set, the transmitter and receiver are mounted in the handset, the ringer is typically in the base, and the dial may be in either the base or handset. The handset cord connects the base to the handset, and the line cord connects the telephone to the telephone line.

More sophisticated telephones may vary from this pattern. A speakerphone has a microphone and speaker in the base in addition to the transmitter and receiver in the handset. Speakerphones allow callers’ hands to be free, and allow more than two people to listen and speak during a call. In a cordless phone, the handset cord is replaced by a radio link between the handset and base, but a line cord is still used. This allows a caller to move about in a limited area while on the telephone. A cellular phone has extremely miniaturized components that make it possible to combine the base and handset into one handheld unit. No line or handset cords are needed with a cellular phone. A cellular phone permits more mobility than a cordless phone.

The electret transmitter is composed of a thin disk of metal-coated plastic and a thicker, hollow metal disk. In the handset, the plastic disk is held slightly above most of the metal disk. The plastic disk is electrically charged, and an electric field is created in the space where the disks do not touch. Sound waves from the caller’s voice cause the plastic disk to vibrate, which changes the distance between the disks, and so changes the intensity of the electric field between them. The variations in the electric field are translated into variations of electric current, which travels across telephone lines. An amplifier using transistors is needed with an electret transmitter to obtain sufficiently strong variations of electric current.

In a rotary dial, the numerals one to nine, followed by zero, are placed in a circle behind round holes in a movable plate. The user places a finger in the hole corresponding to the desired digit and rotates the movable plate clockwise until the user’s finger hits the finger stop; then the user removes the finger. A spring mechanism causes the plate to return to its starting position, and, while the plate is turning, the mechanism opens an electrical switch the number of times equal to the dial digit. Zero receives ten switch openings since it is the last digit on the dial. The result is a number of 'dial pulses' in the electrical current flowing between the telephone set and the exchange. Equipment at the exchange counts these pulses to determine the number being called.

The rotary dial has been used since the 1920s. But mechanical dials are expensive to repair and the rotary-dialing process itself is slow, especially if a long string of digits is dialed. The development of inexpensive and reliable amplification provided by the introduction of the transistor in the 1960s made practical the design of a dialing system based on the transmission of relatively low power tones instead of the higher-power dial pulses.

Today most telephones have push buttons instead of a rotary dial. Touch-Tone is an optional service, and telephone companies still maintain the ability to receive pulse dialing. Push-button telephones usually have a switch on the base that the customer can set to determine whether the telephone will send pulses or tones.

Students use a cellular radio telephone, also known as a cell phone. As cell phones have grown in popularity, they have also decreased in size.

Tom Merton/Getty Images

A cellular telephone is designed to give the user maximum freedom of movement while using a telephone. A cellular telephone uses radio signals to communicate between the set and an antenna. The served area is divided into cells something like a honeycomb, and an antenna is placed within each cell and connected by telephone lines to one exchange devoted to cellular-telephone calls. This exchange connects cellular telephones to one another or transfers the call to a regular exchange if the call is between a cellular telephone and a noncellular telephone. The special cellular exchange, through computer control, selects the antenna closest to the telephone when service is requested. As the telephone roams, the exchange automatically determines when to change the serving cell based on the power of the radio signal received simultaneously at adjacent sites. This change occurs without interrupting conversation. Practical power considerations limit the distance between the telephone and the nearest cellular antenna, and since cellular phones use radio signals, it is very easy for unauthorized people to access communications carried out over cellular phones. Currently, digital cellular phones are gaining in popularity because the radio signals are harder to intercept and decode.

Once the dial tone is heard, the caller uses a rotary or push-button dial mounted either on the handset or base to enter a sequence of digits, the telephone number of the called party. The switching equipment in the exchange removes the dial tone from the line after the first digit is received and, after receiving the last digit, determines whether the called party is in the same exchange or a different exchange. If the called party is in the same exchange, bursts of ringing current are applied to the called party’s line. Each telephone contains a ringer that responds to a specific electric frequency. When the called party answers the telephone by picking up the handset, steady current starts to flow in the called party’s line and is detected by the exchange. The exchange then stops applying ringing and sets up a connection between the caller and the called party.

If the called party is in a different exchange from the caller, the caller’s exchange sets up a connection over the telephone network to the called party’s exchange. The called exchange then handles the process of ringing, detecting an answer, and notifying the calling exchange and billing machinery when the call is completed (in telephone terminology, a call is completed when the called party answers, not when the conversation is over).

When the conversation is over, one or both parties hang up by replacing their handset on the base, stopping the flow of current. The exchange then initiates the process of taking down the connection, including notifying billing equipment of the duration of the call if appropriate. Billing equipment may or may not be involved because calls within the local calling area, which includes several nearby exchanges, may be either flat rate or message rate. In flat-rate service, the subscriber is allowed an unlimited number of calls for a fixed fee each month. For message-rate subscribers, each call involves a charge that depends on the distance between the calling and called parties and the duration of the call. A long-distance call is a call out of the local calling area and is always billed as a message-rate call.

Before automatic exchanges were invented, all calls were placed through manual exchanges in which a small light on a switchboard alerted an operator that a subscriber wanted service. The operator inserted an insulated electrical cable into a jack corresponding to the subscriber requesting service. This allowed the operator and the subscriber to converse. The caller told the operator the called party’s name, and the operator used another cord adjacent to the first to plug into the called party’s jack and then operated a key (another type of electrical switch) that connected ringing current to the called party’s telephone. The operator listened for the called party to answer, and then disconnected to ensure the privacy of the call.

Today there are no telephones served by manual exchanges in the United States. All telephone subscribers are served by automatic exchanges, which perform the functions of the human operator. The number being dialed is stored and then passed to the exchange’s central computer, which in turn operates the switch to complete the call or routes it to a higher-level switch for further processing.

Today’s automatic exchanges use a pair of computers, one running the program that provides service, and the second monitoring the operation of the first, ready to take over in a few seconds in the event of an equipment failure.

Early telephone exchanges, a grouping of 10,000 individual subscriber numbers, were originally given names corresponding to their town or location within a city, such as Murray Hill or Market. When the dialing area grew to cover more than one exchange, there was a need for the dial to transmit letters as well as numbers. This problem was solved by equating three letters to each digit on the dial except for the one and the zero. Each number from two to nine represented three letters, so there was room for only 24 letters. Q and Z were left off the dial because these letters rarely appear in place-names. In dialing, the first two letters of each exchange name were used ahead of the rest of the subscriber’s number, and all exchange names were standardized as two letters and a digit. Eventually the place-names were replaced with their equivalent digits, giving us our current U.S. and Canadian seven-digit telephone numbers. In other parts of the world, a number may consist of more or less than seven digits.

The greatly expanded information-processing capability of modern computers permits Direct Distance Dialing, with which a subscriber can automatically place a call to a distant city without needing the services of a human operator to determine the appropriate routing path through the network. Computers in the switching machines used for long-distance calls store the routing information in their electronic memory. A toll-switching machine may store several different possible routes for a call. As telephone traffic becomes heavier during the day, some routes may become unavailable. The toll switch will then select a less direct alternate route to permit the completion of the call.