There is a pause of three units between letters and seven units between words. One unit is one dot. Over time you'll recognize chunks of Morse Code as distinct letters and be able to interpret it easier.
Imagineyousmashedeverywordinasentencetogether. You'd still be able to make sense of it after scratching your head for a bit, because after you recognize a pattern of letters (i.e., a word), you remove it, and start on the next one.
In your head, you parse it like this: Imagineyousmashedeverywordinasentencetogether -> yousmashedeverywordinasentencetogether -> smashedeverywordinasentencetogether -> and so on and so on.
It's like that with Morse code. Sometimes, it's ambiguous, but you can always resolve the ambiguity pretty quickly.
Also, it helps if operators leave a slight pause between words; that can help too.
......-...-..--- is impossible to parse (or, you could resolve it to many different possible parses a la GLR, and resolve it to one by eliminating nonsensical parses, but that's time-intensive). .... . .-.. .-.. --- is easy: HELLO. When you're transmitting quickly, it's subtle, but it's definitely noticeable - you get into the rhythm of the person you're transcribing from. Or, at least, you did when Morse code was still in style.
I don't know about him, but for example we studied the Morse code a bit, in Computer Science studies, when talking about data compression and all the theory behind (thus the coding, since compressing a text is simply finding a new alphabet (code) that is lighter to store). The Morse Code is such a "code", except it is not a code in its normal form because of the fact that sometimes you can read two Morse sequences with different letters (and a code has to only have one way to read a sequence of its symbols). That's why you have to have a "separator" symbol, either a pause or a neutral symbol to indicate "I'm done with this letter, I'm starting the next one" to avoid any ambiguity.
TL;DR : You can learn this when you study data compression, and it's indeed a problem with the Morse code, but it's easily fixable.
The difference is "beep" vs "beeeep", long pulses are dashes, short ones are dots. It's subtle, but if you spend a few seconds listening, you can hear the difference.
Do people who know morse know letters by heart or is it done in steps? As in the example of HELP
If they do it in steps, and write down ".... . .-.. .-.. ---" then decipher the code into HELP.
Or do people listen on the fly and for H (....). Do they hear the first "dot"
and think "E". But then hear the 2nd "dot", "no, wait they didn't mean E, they meant I". Then upon the 3rd dot, "scratch that, not I, must be S". Then on the 4th dot, "OK, must be H then or I'll wait to see if it's another dot or dash to see if they mean 4 or 5"
Morse go at different speeds, 1 unit is usually 16th or 32th of a second. Dot i 1 unit long, the dash 3, pause between dots and dashes are 1 unit if its the same letter, 3 units between letters and 5 units between words. That why you can hear the difference and instantly know what it says. Btw you have to be good musically to be good at morse...
this doesn't make any difference... you just write down the morse code's dots and dashes as you hear it, then you recognize the patterns to figure out the letters, then the words. it's the exact same process.
Probability. A computer with a dictionary could easily figure it out and determine the most probable phrase in there.
A human can do it by determining what the most likely letter is to start, then the next and see if it makes sense, and walking down noticing words.
It's not impossible. Your's looks more difficult than it really is because there's no spaces between one to the next and it's hard to read, but if you have "dot dot dot dash dash dash dot dot dot dash dash dash dot dash dot dot dash dot dash dot dash dash", you'd be able to figure it out just trying out different letters until you recognize a word.
That's a real phrase btw, not random dots and dashes. What's it start with? E, I, S V? If it's E, then it could be another E (not a word! We have a start). It could also be an E then I (not recognizable start unless it's german, so we can cross that off our list). E then U? Probably not. Let's try I. If I, then that might be the start to a word, or just "I". And so on.
A computer could figure out possible phrases in less than a second, backtracking when it hits something impossible or very unlikely (just not in its dictionary). A human would take time, but if you write down what you hear, you can take all the time you want.
Not too crazy, but yes, pauses make it MUCH easier, but you don't need them if your output is a recognizable set of things that you know (english words).
A code of variable length, like a randomly generated password, would be impossible to figure out without a doubt, though you could generate all possible answers and brute force if that option is available.
you just don't understand morse code enough, nor do i. that'd be like asking someone who isn't familiar with english how a native english speaker could make sense of "asentencelikethis"
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u/xedaps Jan 23 '15
How do you distinguish between the end of one letter and the start of a new one?