|PDH Online Course Description||PDH Units/
Learning Units (Hours)
When Alexander Graham Bell demonstrated his new invention – the telephone, at the Philadelphia Centennial Exposition in 1876, some were amused, some dismissed it outright, some considered it a kind of toy while others saw the potential for voice communication within a limited distance (i.e. inter-city). However, for Mr. Bell and the few who dared to dream with him, there was the promise of nationwide and, potentially, worldwide communication via the human voice. To the patent office, the telephone was designated simply as: An improvement in telegraphy. The first telephones used a grounded circuit which limited telephone communication to about twenty miles. In 1884 a two-wire metallic circuit connected Boston and New York and by the Transposition Principle, telephone communication up to a thousand miles was possible by 1892. With the Loading Coil and Phantom Circuit, telephony at distances greater than 1K-miles was achieved by the early 20th Century. Further technical improvements such as dial service, vacuum tube repeaters, better wire, co-axial cable, microwave transmission and the introduction of the transistor, steady improvement in long-distance telephone communication was achieved by the middle of the 20th Century. In 1927, it took about five minutes to complete a long-distance call. By the early 1950s, it was a matter of seconds thanks to people who believed in Mr. Bell’s big idea of connecting the world via the human voice.
This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.
NY PE & PLS: You must choose courses that are technical in nature or related to matters of laws and ethics contributing to the health and welfare of the public. NY Board does not accept courses related to office management, risk management, leadership, marketing, accounting, financial planning, real estate, and basic CAD. Specific course topics that are on the borderline and are not acceptable by the NY Board have been noted under the course description on our website.