{"id":60,"date":"2018-12-07T13:43:42","date_gmt":"2018-12-07T13:43:42","guid":{"rendered":"http:\/\/burnhamradioclub.co.uk\/?page_id=60"},"modified":"2019-02-09T13:37:25","modified_gmt":"2019-02-09T13:37:25","slug":"cw-and-morse-code","status":"publish","type":"page","link":"https:\/\/burnhamradioclub.co.uk\/index.php\/transmission-modes\/cw-and-morse-code\/","title":{"rendered":"CW and Morse Code"},"content":{"rendered":"

CW Morse\u00a0<\/a>Persistence of radio telegraphy<\/h2>\n

Early radio transmitters could not be\u00a0modulated\u00a0to transmit speech, and so CW radio telegraphy was the only form of communication available. CW still remains a viable form of radio communication many years after voice transmission was perfected, because simple, robust transmitters can be used, and because its signals are the simplest of the forms of\u00a0modulation\u00a0able to penetrate interference. The low bandwidth of the code signal, due in part to low information transmission rate, allows very selective filters to be used in the receiver, which block out much of the radio noise that would otherwise reduce the intelligibility of the signal.<\/p>\n

Continuous-wave radio was called\u00a0radiotelegraphy\u00a0because like the\u00a0telegraph, it worked by means of a simple switch to transmit\u00a0Morse code. However, instead of controlling the electricity in a cross-country wire, the switch controlled the power sent to a radio\u00a0transmitter. This mode is still in common use by\u00a0amateur radio\u00a0operators.<\/p>\n

In military communications and\u00a0amateur radio\u00a0the terms “CW” and “Morse code” are often used interchangeably, despite the distinctions between the two. Aside from radio signals, Morse code may be sent using\u00a0direct current\u00a0in wires, sound, or light, for example. For radio signals, a carrier wave is keyed on and off to represent the dots and dashes of the code elements. The carrier’s amplitude and frequency remains\u00a0constant\u00a0during each code element. At the receiver, the received signal is mixed with a\u00a0heterodyne\u00a0signal from a BFO (beat frequency oscillator) to change the radio frequency impulses to sound. Though most commercial traffic has now ceased operation using Morse it is still popular with amateur radio operators.\u00a0Non-directional beacons (NDB)and\u00a0VHF omnidirectional radio range (VOR)\u00a0used in air navigation use Morse to transmit their identifier.<\/p>\n

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Welcome to Burnham Amateur Radio Club in Morse<\/p>\n

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<\/a>Play \/ Pause<\/td>\n\u00a0