I don't understand this description. How are electromagnetic waves related to sound (voice frequency)?--Georg Muntingh (diskussion) 27. jun 2019, 21:38 (CEST)

True, this sounds rather odd. Neither the English nor the Italian articles support this usage. We will have to examine and probably rewrite it completely. Ditlev Petersen (diskussion) 27. jun 2019, 21:44 (CEST)
They are only related by their frequency. If you have an old fashioned telephone line (land line), the audio signals are electromagnetic waves at the frequency the voices have. And 300-3000 Hz is the band that telephone lines can carry. Later, in the transition to semidigital tecnology, we had in-band signalling - tones within 300-3000Hz controlling functions while the line carried speak. That could be the keying tone for a transmitter, being filtered away from the Tx audio. --Jørgen (diskussion) 27. jun 2019, 21:46 (CEST)
But if radio frequencies are used on the telephoneline to carry more connections then the frequencies would be far higher. Also voice transmitted pure (old style, one connection, one pair of wires) is electromagnetic waves the correct term. The current to my speakers are not considered to be an electromagnetic transmission? The electromagnetic waves DO emit from the cables and can be picked up - but who thinks like that? This is not 1916. We seem to mix things up here. Ditlev Petersen (diskussion) 27. jun 2019, 21:53 (CEST)
You can transmit at VF wireless! It is very long waves and needs a very long antenna. --Jørgen (diskussion) 27. jun 2019, 22:41 (CEST)
Exactly, that is why VF seems slightly misplaced here. But during WW1 simple telephone connections were sometimes "tapped" wirelessly. A very long wire along the trenches could pick op telephone communications from the other side. I also remember having read that a telephone on a Scottich island was connected to the mainland in the same manner rather than running an expensive sea cable. I think that was before the war. But I am no engineer - it just seems odd comparing to the English or Italian article. They contain an entirely different matter. Ditlev Petersen (diskussion) 27. jun 2019, 22:58 (CEST)
The article has now been moved to the proper name and corrected. --Glenn (diskussion) 20. jul 2021, 12:05 (CEST)
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