multiple-position frequency telegraphy
1Telegraphy — (from the Greek words (τηλε) = far and (γραφειν) = write) is the long distance transmission of written messages without physical transport of letters. Radiotelegraphy or wireless telegraphy transmits messages using radio. Telegraphy includes… …
2Radio — is the transmission of signals, by modulation of electromagnetic waves with frequencies below those of visible light.Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of… …
3Invention of radio — Great Radio Controversy redirects here. For the album by the band Tesla, see The Great Radio Controversy. Contents 1 Physics of wireless signalling 2 Theory of electromagnetism …
4Distress radiobeacon — PLB redirects here. For other uses, see PLB (disambiguation). Emergency position indicating radio beacons or EPIRBs Distress radio beacons, also known as emergency beacons, ELT or EPIRB, are tracking transmitters which aid in the detection and… …
5Transmission line — This article is about the radio frequency transmission line. For the power transmission line, see electric power transmission. In communications and electronic engineering, a transmission line is a specialized cable designed to carry alternating… …
6List of Tesla patents — Below is a list of Tesla patents. Dr. Nikola Tesla was an inventor who obtained around 300 patents [Snezana Sarbo, [http://www.tesla symp06.org/papers/Tesla Symp06 Sarboh.pdfNikola Tesla s Patents] , Sixth International Symposium Nikola Tesla,… …
7Cellular network — Top of a cellular radio tower A cellular network is a radio network distributed over land areas called cells, each served by at least one fixed location transceiver known as a cell site or base station. When joined together these cells provide… …
8Morse code — Chart of the Morse code letters and numerals Morse code is a method of transmitting textual information as a series of on off tones, lights, or clicks that can …
9History of radar — The history of radar starts with experiments by Heinrich Hertz in the late 19th century that showed that radio waves were reflected by metallic objects. This possibility was suggested in James Clerk Maxwell s seminal work on electromagnetism.… …
10Television antenna — A Winegard HD 7084P 68 element VHF/UHF aerial antenna A television antenna, or TV aerial, is an antenna specifically designed for the reception of over the air broadcast television signals, which are transmitted at frequencies from about 41 to… …
