I'm currently picking up signal from a beacon using RTL-SDR and decoding the Morse code on a computer using gMFSK program. The beacon is sending message which decodes as "T DE YU1VHF LOC KN04OO".
I still haven't started learning how to decode the Morse code by "hand".

From what I understand, DE is from "this is", YU1VHF is the beacon's callsign and LOC KN04OO looks like Maidenhead system location. The only part which I don't get at the moment is "T".

Any ideas what that would be?

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    $\begingroup$ The rest of your guesses as to the content of the beacon are correct - DE is better translated as "from". I have a guess as to the T - T is sometimes used along with some other letters to indicate the number 0 - perhaps with a single long dash - or it could be used to indicate the start of the beacon - but are you sure that there isn't anything before the T that you're missing or that isn't being decoded? a T should just be a dash, all alone. $\endgroup$ – Dan KD2EE Nov 24 '13 at 22:17
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    $\begingroup$ @Dan KD2EE♦ I think you're up to something here... The beacon emits a continuous 30 second long tone when it's not emitting the data. It stops the tone for one pause between the characters and then starts sending the text for the next 30 seconds. After listening more carefully to the transmission and looking at the gMFSK output, it seems that the program picks the long tone as the letter "T". To me this looks line a nice example of dangers of simply relying on a computer to decode Morse code. $\endgroup$ – AndrejaKo Nov 24 '13 at 23:03
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    $\begingroup$ @AndrejaKo That comment ought to be an answer. $\endgroup$ – Kevin Reid AG6YO Nov 25 '13 at 4:44
  • $\begingroup$ @Kevin Reid Yeah, I agree. I'm just giving time to others, just in case someone thinks of something a bit smarter than what I wrote in my comment. $\endgroup$ – AndrejaKo Nov 25 '13 at 7:43

As mentioned in my comment, it appears that the software I'm using, gMFSK, is decoding the long tone as a letter "T", because there is a short pause between the tone beacon transmits and the message itself.

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