transmitter
Quick Summary
A transmitter is an electronic device that sends out signals. In a telephone, the transmitter acts as a microphone, converting the speaker's voice into electrical signals by varying the resistance of carbon granules or an electric field. For radar systems, transmitters generate high-power signals that are radiated by an antenna. These can be magnetrons, klystrons, traveling-wave tubes, or solid-state devices like transistors, each with advantages for different applications. In broadcast television, transmitters amplify and combine signals onto a carrier wave for transmission via an antenna. Transmitters are also fundamental in electronic eavesdropping, where they can be miniaturized and concealed to intercept conversations.1234
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- electronic eavesdropping
…listening device is a radio transmitter made out of integrated microcircuits. One hundred typical microcircuits can be made on a piece of material smaller and thinner than a postage stamp. A transmitter so constructed can be concealed in a playing card or behind wallpaper.
Read More…listening device is a radio transmitter made out of integrated microcircuits. One hundred typical microcircuits can be made on a piece of material smaller and thinner than a postage stamp. A transmitter so constructed can be concealed in a playing card or behind wallpaper.
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falconryHunting and training techniques…many falconers now attach a transmitter to a trained hawk so that it may be tracked down with a radio-receiver unit.
Read More…many falconers now attach a transmitter to a trained hawk so that it may be tracked down with a radio-receiver unit.
Read More- radarTransmitters
The transmitter of a radar system must be efficient, reliable, not too large in size and weight, and easily maintained, as well as have the wide bandwidth and high power that are characteristic of radar applications. In general, the transmitter must generate low-noise, stable…
Read MoreThe transmitter of a radar system must be efficient, reliable, not too large in size and weight, and easily maintained, as well as have the wide bandwidth and high power that are characteristic of radar applications. In general, the transmitter must generate low-noise, stable…
Read More - radarTransmitter power and antenna size
The maximum range of a radar system depends in large part on the average power of its transmitter and the physical size of its antenna. (In technical terms, this is called the power-aperture product.) There are practical limits to each.…
Read MoreThe maximum range of a radar system depends in large part on the average power of its transmitter and the physical size of its antenna. (In technical terms, this is called the power-aperture product.) There are practical limits to each.…
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faxStandard fax transmissionCommunication between a transmitting and a receiving fax machine opens with the dialing of the telephone number of the receiving machine. This begins a process known as the “handshake,” in which the two machines exchange signals that establish compatible features such as modem speed, source code, and printing…
Read MoreCommunication between a transmitting and a receiving fax machine opens with the dialing of the telephone number of the receiving machine. This begins a process known as the “handshake,” in which the two machines exchange signals that establish compatible features such as modem speed, source code, and printing…
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telecommunications mediaThe free-space channel…of an indoor free-space optical transmitter is the handheld infrared remote control for television and high-fidelity audio systems. Free-space optical systems also are quite common in measurement and remote sensing applications, such as optical range-finding and velocity determination, industrial quality control, and laser altimetry radar (known as LIDAR).
Read More…of an indoor free-space optical transmitter is the handheld infrared remote control for television and high-fidelity audio systems. Free-space optical systems also are quite common in measurement and remote sensing applications, such as optical range-finding and velocity determination, industrial quality control, and laser altimetry radar (known as LIDAR).
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telegraphThe first transmitters and receiversThe electric telegraph did not burst suddenly upon the scene but rather resulted from a scientific evolution that had been taking place since the 18th century in the field of electricity. One of the key developments was the invention of the voltaic…
Read MoreThe electric telegraph did not burst suddenly upon the scene but rather resulted from a scientific evolution that had been taking place since the 18th century in the field of electricity. One of the key developments was the invention of the voltaic…
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telephoneTransmitterThe transmitter is essentially a tiny microphone located in the mouthpiece of the telephone’s handset. It converts the vibrations of the speaker’s voice into variations in the direct current flowing through the set from the power source.
Read MoreThe transmitter is essentially a tiny microphone located in the mouthpiece of the telephone’s handset. It converts the vibrations of the speaker’s voice into variations in the direct current flowing through the set from the power source.
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Lee de ForestInvention of the Audion tube…properly modulated, was capable of transmitting speech and music. When appropriately modified, this single invention was capable of either transmitting, receiving, or amplifying radio signals.
Read More…properly modulated, was capable of transmitting speech and music. When appropriately modified, this single invention was capable of either transmitting, receiving, or amplifying radio signals.
Read More- Henry Joseph Round
…designed and installed several important transmitters. From one, at Ballybunion, Ire., the first radio telephone messages were sent from Europe across the Atlantic; two others were the first public broadcasting stations in England; and another, at Carnarvon, Wales, sent radio signals that were received in Australia. He also devised radio…
Read More…designed and installed several important transmitters. From one, at Ballybunion, Ire., the first radio telephone messages were sent from Europe across the Atlantic; two others were the first public broadcasting stations in England; and another, at Carnarvon, Wales, sent radio signals that were received in Australia. He also devised radio…
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