![]() Also called an antenna-matching network, impedance-matching network or Transmatch.Īutopatch - A device that allows repeater users to make telephone calls through a repeater.īalun - Contraction for balanced to unbalanced. Few amateurs use double-sideband voice AM, but a variation, known as single sideband, is very popular.Īntenna - A device that picks up or sends out radio frequency energy.Īntenna switch - A switch used to connect one transmitter, receiver or transceiver to several different antennas.Īntenna tuner - A device that matches the antenna system input impedance to the transmitter, receiver or transceiver output impedance. Shortwave broadcast stations use this type of AM, as do stations in the Standard Broadcast Band (535-1710 kHz). In double-sideband voice AM transmission, we use the voice information to vary (modulate) the amplitude of an RF carrier. (Numbers written as a multiple of some power are expressed in exponential notation, as shown here.Īmplitude modulation (AM) - A method of combining an information signal and an RF (radio-frequency) carrier. If we could count electrons, we would find that if there are 6.24 × 1018 electrons moving past a point in one second, we have a current of one ampere. Current is a measure of the electron flow through a circuit. This direction reversal continues at a rate that depends on the frequency of the ac.Īmateur operator - A person holding a written authorization to be the control operator of an amateur station.Īmateur service - A radiocommunication service for the purpose of self-training, intercommunication and technical investigations carried out by amateurs, that is, duly authorized persons interested in radio technique solely with a personal aim and without pecuniary interest.Īmateur station - A station licensed in the amateur service, including necessary equipment, used for amateur communication.Īmmeter - A test instrument that measures currentĪmpere (A) - The basic unit of electrical current. The applied voltage is also changing polarity. Today, amateurs use it more in the manner that James Reid had intended that it be used -a "friendly word between operators."Īlternating current (ac) - Electrical current that flows first in one direction in a wire and then in the other. "Best regards" has remained ever since as the "put-it-down-in-black-and-white" meaning of 73 but it has acquired overtones of much warmer meaning. Edison's Telegraphy Self-Taught shows a return to "accept my compliments." By 1908, however, a later edition of the Dodge Manual gives us today's definition of "best regards" with a backward look at the older meaning in another part of the work where it also lists it as "compliments." Dodge's The Telegraph Instructor shows it merely as "compliments." The Twentieth Century Manual of Railway and Commercial Telegraphy defines it two ways, one listing as "my compliments to you " but in the glossary of abbreviations it is merely "compliments." Theodore A. Over the years from 1859 to 1900, the many manuals of telegraphy show variations of this meaning. Here, in the 92 Code, 73 changes to "accept my compliments," which was in keeping with the florid language of that era. In 1859, the Western Union Company set up the standard "92 Code." A list of numerals from one to 92 was compiled to indicate a series of prepared phrases for use by the operators on the wires. ![]() In the National Telegraph Convention, the numeral was changed to a friendly "word" between operators. The first authentic use of 73 is in the publication The National Telegraph Review and Operators' Guide, first published in April 1857. 73 - Ham lingo for "best regards." Used on both phone and CW toward the end of a contact.
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