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Long-distance calling

Long-distance calling is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Long-distance calling rather than just read about it. In short: In telecommunications, a long-distance call (U.S.) or trunk call (also known as a toll call in the UK ) is a telephone call made to a location outside a defined local calling area. Long-distance calls are typically charged a higher billing rate than local calls.

Long-distance calling — main illustration
Long-distance calling — illustration

Key takeaways

  • Long-distance calling belongs to science; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Long-distance calling to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Long-distance calling from memory before moving on to harder problems.

Reference excerpt

In telecommunications, a long-distance call (U.S.) or trunk call (also known as a toll call in the UK ) is a telephone call made to a location outside a defined local calling area. Long-distance calls are typically charged a higher billing rate than local calls. The term is not necessarily synonymous with placing calls to another telephone area code. Long-distance calls are classified into two categories: national or domestic calls which connect two points within the same country, and international calls which connect two points in different countries. Within the United States there is a further division into long-distance calls within a single state (intrastate) and interstate calls, which are subject to different regulations (counter-intuitively, calls within states are usually more expensive than interstate calls). Not all interstate calls are long-distance calls. Since 1984 there has also been a distinction between intra-local access and transport area (LATA) calls and those between different LATAs, whose boundaries are not necessarily state boundaries. Before direct distance dialing (DDD), all long-distance calls were established by special switchboard operators (long-distance operators) even in exchanges where calls within the local exchange were dialed directly. Completion of long-distance calls was time-consuming and costly as each call was handled by multiple operators in multiple cities. Record keeping was also more complex, as the duration of every toll call had to be manually recorded for billing purposes. In many less-developed countries, such as Spain, Mexico, Brazil, and Egypt, calls were placed at a central office the caller went to, filled out a paper slip, sometimes paid in advance for the call, and then waited for it to be connected. In Spain these were known as locutorios, literally "a place to talk". In towns too small to support a phone office, placing long-distance calls was a sideline for some businesses with telephones, such as pharmacies. In some countries, such as Canada and the United States, long-distance rates were historically kept artificially high to subsidize unprofitable flat-rate local residential services. Intense competition between long-distance telephone companies narrowed these gaps significantly in most developed nations in the late 20th century. The cost of international calls varies dramatically among countries. The receiving country has total discretion in specifying what the caller should be charged (by the originating company, who in a separate transaction transfers these funds to the destination country) for the cost of connecting the incoming international call with the destination customer anywhere in the receiving country. This has only a loose, and in some cases no, relation to the actual cost. Some less-developed countries, or their telephone company(s), use these fees as a revenue source.

History On August 10, 1876, Alexander Graham Bell made a call via the telegraph line between Brantford and Paris, Ontario, eight miles (thirteen kilometres) distant. This test was said by many sources to be the "world's first long-distance call". This test certainly proved that the telephone could work over long distances, at least as a one-way call.

Following a major flood in 1877, the president of the Chesapeake and Ohio Canal, Arthur Pue Gorman, hired J. Frank Morrison to build a communications line. The initial plan was for a telegraph, but due to rapid advances in technology, the project was changed to a telephone system which promised lower operating costs. Morrison's construction gangs worked through the summer of 1879, completing a line that stretched over 180 miles from Georgetown to Cumberland, Maryland. The system used forty-eight Edison Universal Telephones stationed at intervals along the route, and was considered a pioneering achievement, the world's first commercial long distance telephone service.

In 1891, AT&T built an interconnect telephone network, which reached from New York to Chicago, the technological limit for non-amplified wiring. Users often did not use their own phone for such connections, but made an appointment to use a special long-distance telephone booth or "silence cabinet" equipped with 4-wire telephones and other advanced technology. The invention of loading coils extended the range to Denver in 1911, again reaching a technological limit. A major research venture and contest led to the development of the audion—originally invented by Lee De Forest and greatly improved by others in the years between 1907 and 1914—which provided the means for telephone signals to reach from coast to coast. Such transcontinental calling was made possible in 1914 but was not showcased until early 1915, as a promotion for the upcoming Panama–Pacific International Exposition in San Francisco in the spring of the same year. On January 25, 1915, Alexander Graham Bell ceremonially initiated the first transcontinental telephone call from 15 Dey Street in New York City, which was received by his former assistant Thomas A. Watson at 333 Grant Avenue in San Francisco. This process, nevertheless, involved five intermediary telephone operators and took 23 minutes to connect by manually patching in the route of the call.

"On Oct. 9, 1876, Alexander Graham Bell and Thomas A. Watson talked by telephone to each other over a two-mile wire stretched between Cambridge and Boston. It was the first wire conversation ever held. Yesterday afternoon the same two men talked by telephone to each other over a 3,400-mile wire between New York and San Francisco. Dr. Bell, the veteran inventor of the telephone, was in New York, and Mr. Watson, his former associate, was on the other side of the continent. They heard each other much more distinctly than they did in their first talk thirty-eight years ago." On November 10, 1951, the first direct dial long-distance telephone call in North America was placed from Mayor M. Leslie Denning of Englewood, New Jersey to Mayor Frank Osborne of Alameda, California via AT&T's Bell System. The ten-digit call (seven digits plus a three-digit area code) was connected automatically within 18 seconds. The first subscriber trunk dialing in the United Kingdom was deployed December 5, 1958 with Elizabeth II placing a call from Bristol to Edinburgh.

… excerpt ends here. Continue reading the full article.

Illustrations

Long-distance calling: Site of one end of the first U.S. intercity[citation needed] [5]telephone call in 1876 in Cambridge, Massachusetts. Another early call between cities had been made in Canada by telephone inventor Alexander Graham Bell.[6]
Site of one end of the first U.S. intercity[citation needed] [5]telephone call in 1876 in Cambridge, Massachusetts. Another early call between cities had been made in Canada by telephone inventor Alexander Graham Bell.[6]

Worked examples

Example 1 — a first encounter with Long-distance calling

Start with the simplest possible case. Write down what Long-distance calling claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Long-distance calling before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Long-distance calling ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Long-distance calling

In research
Long-distance calling appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Long-distance calling in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Long-distance calling is common in secondary-school and first-year university syllabi. It links to neighbouring topics Distance, Telephone services, so understanding it makes those chapters shorter.
In everyday life
Look for Long-distance calling outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Long-distance calling in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Long-distance calling means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Long-distance calling out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Long-distance calling in simple terms?

In telecommunications, a long-distance call (U.S.) or trunk call (also known as a toll call in the UK ) is a telephone call made to a location outside a defined local calling area. Long-distance calls are typically charged a higher billing rate than local calls.

Why does Long-distance calling matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Long-distance calling?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Long-distance calling.

Tags

  • Distance
  • Telephone services

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