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Ok , so I know very very little about amateur radio, I've hear in some websdr frequencies morse code transmissions and I've got quite curious, what are they?

Who sends moresecode transmissions nowadays , are radio amateurs or the military?

If I knew morse code could I understand it?

I meant like 1820 at http://hackgreensdr.org:8901/

Jonathan DS
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  • I'm really sorry if it's duplicated or not belongs here, i REALLY know nothing about ham radio and am just curious – Jonathan DS Jan 27 '14 at 13:49
  • actually i would like more of an explanation of what am i hearing at websdr should i provide further details? – Jonathan DS Jan 28 '14 at 12:12
  • yes you should. – Phil Frost - W8II Jan 28 '14 at 12:32
  • ok is 5 hours to long? i'm at work and java is blocked here :/ – Jonathan DS Jan 28 '14 at 12:38
  • At the rate this site generates new questions, you will still be on the front page in 5 hours. – Phil Frost - W8II Jan 28 '14 at 12:42
  • If you think of Morse as a simple, relatively slow but reliable and low bandwidth digital mode that can be coded and decoded by humans, then what you're really asking is "What use is a slow, low bandwidth digital mode that doesn't require a computer?" There are many answers to that question, though, and I'd say this is really too broad for the site. – Adam Davis Jan 28 '14 at 23:02
  • You will have to reference whatever it was you were wondering about in a way that is time invariant. Whatever was at 1820 kHz is no longer there. If you are asking about a specific thing, then you should probably also edit the entire question accordingly. – Phil Frost - W8II Jan 30 '14 at 01:06

3 Answers3

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The US military no longer uses Morse Code. Amateur radio operators still use if for a variety of reasons many of which were explored in this question.

Morse code isn't difficult to learn, but like anything, takes some practice. There are also software programs that can work with you SDR that will decode Morse (to varying degrees of success depending on signal quality and the quality of the sent Morse code).

Community
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WPrecht
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Amateur radio operators still use Morse Code, as do a few other government services, such as aviation beacons, etc. These Morse Code signals are usually just encoded text (roughly related to other text encoding schemes such as ACSII or Braille).

Morse code allows an extremely simple on-off transmission scheme (about as simple a modulation as can be done). Letters and numbers can be encoded into sequences of long and short on-off signals, each character having a specific pattern in time. Originally it was thought that these time sequences would have to be graphically charted out and read, or translated by some sort of machine. But it turned out that after hearing it for awhile (and learning the distinctive sound of each letter) telegraph and radio operators could understand (and type out for telegrams, etc.) the Morse Code encoded messages just by listening to the relay ticks or the radio sidetones.

So, yes, if you learn what all the letters sound like (fast enough, which takes a bit of practice), you might be able to understand the message just by listening.

hotpaw2
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QRP (low power) is a challenging area of amateur radio that uses morse code -- mainly because every bit of signal strength matters.

CW makes very efficient use of the available power, compared to some other modes.

gdc
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