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LCWO Discussion Forum [Atom LCWO Forum Feed]

This is a simple discussion forum for LCWO users. Feel free to use it for any kind of discussion related to this website.

Thread: Decreasing the frequency of "old" letters

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AuthorText


Posted: 2011-05-13 17:37
I've been trying to do the Koch lessons to learn the charaters, but I've noticed that it seems to be an equal probability of getting each letter.

For example, the first lesson only has two characters and they come up about an equal number of times, but now I'm on lesson 17, letter "F", and the last few times I have practiced, it has come up about only about 3 or 4 times.

Is there a way to decrease the frequency of the letters that I already know really well, and increse the ones that I don't know, sort of like the Morse Machine?
[deleted]

Posted: 2011-05-13 19:14
Type in google:
g4fon koch method morse trainer 9.2 download

and you find a free downloadable program with random QSO's, words, koch and you can select the characters for Koch.
Also qrm qsb qrn chirp irregular fist etc.
R? k


Posted: 2011-05-18 17:13
w5smd:
Is there a way to decrease the frequency of the letters that I already know really well, and increse the ones that I don't know, sort of like the Morse Machine?

Not as far as I can tell, but it'd be a neat feature, particularly for the later Koch lessons...
Administrator


Posted: 2011-05-27 03:58
This is a valid and good point, I'll implement this.

73
Fabian


Posted: 2011-05-28 23:14
Now that I am on lesson 22, I have found this same problem. Now I alternate the lessons with Code Groups and choose the letters that are new or having problems with through the Change CW settings. I usually use about 6 different letters, sometimes adding more or changing with other letters.
Administrator


Posted: 2011-06-13 12:08
There's now a regression in the frequency of "older" letters. It's a linear weighting of the letter probability vs. lesson, startig with a particular minimum value.

There are some parameters that can be tweaked, so if you think the current letters are appearing too often (or still too seldomly), please let me know.

73
Fabian DJ1YFK


Posted: 2011-06-15 13:55
I am noticing the newer letters coming up more often. Thanks.


Posted: 2011-06-26 09:56
Thanks. I've been off-line for three weeks, and you've done lots of improvements in that time! :)


Posted: 2011-10-12 19:10
I guess, as the selection's still somewhat random, it's not all that surprising that sometimes the distribution seems skewed. I'm working on lesson 5 at the moment (K M U R E S) and I just had one exercise where the letters were distributed thus:

S S S S S S S S S S S S S S S
E E E E E
R R R R R R R R R R R
U U U U U U U U U U U U U
M M M M M M M
K K K K K K K K K K K K K K K K K K

...so in this case K was noticeably over-represented and E under-represented. Next exercise it'll be completely different, of course. (Edit) ...and to prove the point, a couple of attempts later this is the distribution:

S S S S S S S S S S S S S S S S
E E E E E E E E E E E E E E E
R R R R R R R R R R R R
U U U U U U U U U
M M M M M M M
K K K K K K K K K K

...which is much nearer an "old is less frequent" distribution.

Not entirely surprisingly, I did a whole lot better on the first (82.9%) than the second (60%).

Ah, the wonder of (pseudo-)random number generators...


Posted: 2011-10-15 17:18
...which leaves me wondering what the adjusted frequencies of the letters are, and whether there's a better way to come up with "random" groups.

There comes a point at which it might make sense to put the required mix of characters into a card deck and shuffle them. That way you'd be certain to have the chosen number of each character, but the catch would be deciding on the size of the deck. For one minute at 14wpm you'd need a deck of 70, which would probably give enough room even in the later lessons to ensure every character occurred at least once, but for one minute sessions you'd run out of space at 8wpm...


Posted: 2011-10-17 10:55
Here's another out-to-lunch selection, this time for lesson 6 (with N as the "new" letter):

N N N N N N N N N N
S S S S S S
E E E E E E E E E E E E
R R R R R R
U U U U U U U U U U U U U U U U U
M M M M M M M M M
K K K K K K K K K

...and one that's even further from the ideal:

N N N N N N
S S S S S S S S S S S S S S S
E E E E E
R R R R R R R R R R
U U U U U U U U U U U U U U
M M M M M M M M
K K K K K K K K K K K

I guess it's not surprising I got my best score so far with that one; it had hardly any new characters in it. The very next one was one of my worst scores. No surprises its distribution looked like this:

N N N N N N N N N N N N N N N N N N N
E E E E E E E
S S S S S S S S S S
R R R R R R R
U U U U U U U
M M M M M
K K K K K K K K K K K K K K

I guess, before I leap ahead to the next lesson I should first check to see whether my "better than 90%" score includes correct identification of any of the new character, just in case it happens to have ended up with hardly any of them there, like this one...

N N N N
S S S S S S S S S S S S
E E E E E E E E E E E E
R R R R R R R R R R
U U U U U U U U U
M M M M M M M M M M
K K K K K K K K K K K K

...and this one (from lesson 7) is even worse...

A A
N N N N N N N N N N N N N N
E E E E E E E
S S S S S S S
R R R R R R
U U U U U U U U
M M M M M M M M M
K K K K K K K K K K K K


Posted: 2012-01-20 19:01
The letter E is a little over-represented in this random distribution from lesson 9:

T T T T T T
P P P P P
A A A A A A
N N N N N
S S S S S
E E E E E E E E E E E E E
R R R R R
U U U U U
M M M M M M
K K K K K K K K K

...so, consequently, the lesson ran a little faster than average. I got one of the Ts correct...
[deleted]

Posted: 2012-01-22 00:10
It has not much sense to count the characters in one or a few lessons.
You may have to count hundered of lessons, or even thousands to notice the difference in probability of occurance of the different characters.

When you throw a perfect dice you will not believe that it is perfect when you throw 6 times six in a row, however that is just a regular case and the probability of occurance is 1/2^6

May be that you are better off when you exercise with 6 characters and when all OK start with a complete different set of 6 characters.
After that excersise alternate with the characters of the groups done, togeter in one new large group and with 6 complete new characters to build up in 5 lessons.

As said by [deleted] above you can use the well known programs MorseCat G4FON and JustlearnMorse for that purpose.


Posted: 2012-01-22 11:22
PAoKDW:
It has not much sense to count the characters in one or a few lessons.


I take your point, but my point is that using totally random characters isn't really the best way to present characters to folks trying to learn new ones; it's better to feed them a steady mix with enough of the new characters for them to pick up. That way, if they get better than 90% correct there's at least a chance that 90% includes some instances of the new character. With some of the mixes I've seen I could have got a 95% score without getting any instances of the new character correct. The scoring doesn't pick that up.

The other advantage of using a non-random mix is that the resultant code speed would be a lot less variable. As it stands, at (say) lesson 9, if you've picked (say) 12wpm, you could get sent code at 10 or 11 wpm (if P is over-represented) or 13 or 14 wpm (if E is over represented). Of course that's more realistic, but for Koch lessons realistic isn't necessarily an advantage.
[deleted]

Posted: 2012-01-22 14:25
OK,

Best should be to care for 20% or 25% of the introduced character to be present in the new lesson. 10 to 15% of the character introduced in the previous lesson and half the probability of each previous learned character in that sequence.

After all this website is an introduction, specially for people that cannot think out the best way to learn what they want to, by theirself.

So what you think can be done better, (I agree with that) is easily obtained without overloading other people, that are so overloaded that they can't distinguish a joke from trolling, when you exercise with the mentioned programs that are indicated in this thread, installed on your computer.


Posted: 2012-01-22 20:26
There's just one problem with all three of those programs...

...You need Windows to run them. ;)

While LCWO works in all sorts of places on quite a variety of systems. It even (just about) worked on an under-powered linux laptop on the wrong end of a Net connection in Kenya that was using a bit of string that wasn't quite wet enough... ;)
[deleted]

Posted: 2012-01-23 00:38
Use WINE or compose your own exercising lessons with text to CW on this website.


Posted: 2012-01-23 09:28
lzlep:
It even (just about) worked on an under-powered linux laptop on the wrong end of a Net connection in Kenya that was using a bit of string that wasn't quite wet enough... ;)

Now that's dedication to training!


Posted: 2012-01-23 17:36
PAoKDW:
Use WINE or compose your own exercising lessons with text to CW on this website.

WINE's not an option, and text2cw only covers part of the service LCWO's Koch lessons provide. It leaves out the checking, scoring and tracking part, which is where the real value lies. Sure, one could cook up a spreadsheet or whatever, but why re-invent the wheel...


Posted: 2012-01-23 18:18
Heh! I thought this last selection was going too well. By half-way through I was wondering whether any Ts were in it. Of course, once I started wondering it all fell apart. I really should have scored more than 77.5%, as, in the end there was exactly one T:

T
P P P P P P
A A A A A A A A A
N N N N N
S S S S S S S S S
E E E E E
R R R R R R R R
U U U U U U U
M M M M M
K K K K K K K K K

I think this lesson's going to take a while...
[deleted]

Posted: 2012-01-29 22:40
When you set in CW options the desired character set of the most recently learned 5 characters, and go to code groups, with option custom characters, you have all you want as far as I can see.


Posted: 2012-02-01 00:14
No, the character distribution will still be random. I might still only get one T and nineteen Ns.

What I'd like is to know that, out of (say) 100 characters, at least (say) 20 will always be the newest, at least 15 the next newest, at least 10 the next after that, at least 5 the next after that, and the remaining 50 evenly distributed among all the current characters.

The order of the characters would still be random, but the distribution would not. The newer characters would be more frequent, and even in the later lessons they would appear frequently.
[deleted]

Posted: 2012-02-01 11:57
When you want the T with 20% probability take the 5 last learned characters and put them in the custom code, nothing else. When you copy those for 100% after a week or so erase the oldest character from the group of 5 and add a new character.


Posted: 2012-02-01 15:01
I don't want "T with 20% probability". Even at that level there is the possibility that there will only be one or two in an exercise. If an exercise is 100 characters long, then I want 20 Ts among those 100 characters, guaranteed, every time. And if I ever get to lesson 40, then I want 20 Xs among the 100 characters, every time.

The whole point of the Koch lessons is to learn the new character each time, in the context of all the other ones (hopefully) learned in earlier lessons. If that new character doesn't come up fairly often then it's hard to learn it. Unfortunately, using random probability to select the characters does mean that, sometimes, the new character doesn't appear often, as some of the examples I've posted above demonstrate. As the number of different characters in the lessons increases, this problem gets worse...

(Of course there are ways I can get round the problem for myself, but they all involve losing the main benefit LCWO offers - a way check results and to track progress that I can use whether I'm at home, or in some far-flung corner of the world.)


Posted: 2012-02-01 16:13
Hi Rick,

First of all: my impression is you have to put in more effort than average and I am impressed by your dedication!

lzlep:

Of course there are ways I can get round the problem for myself, but they all involve losing the main benefit LCWO offers - a way check results and to track progress that I can use whether I'm at home, or in some far-flung corner of the world.


Good point. lcwo provides the ability to convert custom text into mp3. It would be nice if that mp3 could be played and checked like the rest. This way you can provide a text that meets your particular demand, use it for practice and get feedback.

Joep
[deleted]

Posted: 2012-02-03 18:48
jsujis

How the heck do you pronounce your name without choking.

No read first before writing, he wants graphs and error indications, and fixed numbers of occurances per character. In short: he needs his own software designer for free.



Posted: 2012-02-04 14:57
ldeletedl:
jsujis
How the heck do you pronounce your name without choking.

Hi,

My first name is Joep. Pronounced similar to "youp" in English.

ldeletedl:

he wants graphs and error indications, and fixed numbers of occurances per character. In short: he needs his own software designer for free.

Don't we all...

My suggestion would provide graphs and error indications to any custum input file. This would extend the strength of lcwo.
Generating sets of specific practice sets is a remaining task, left to the individual user. This could be done with a (much simpler) script, or by hand in an text editor.

Btw, I searched for your 'presented cigar' proverb from the other treath, but the only (exact) instance google came up with is the one you posted. So I am still in the dark to what it means...

Joep

[deleted]

Posted: 2012-02-05 15:17
[deleted] just pronounce suijs as "noise" with the n changed in s.


Posted: 2012-02-07 21:58
ldeletedl:
In short: he needs his own software designer for free.


Discussion of the merits (or otherwise) of suggested changes should, I think, be useful, provided it's kept positive. I've tried to demonstrate how the existing koch lesson generation falls short of the ideal, and to suggest a method I think would work better. I'd be prepared to do the software work (if the relevant language is one I know), but this is not my site, and I don't have access to its code or permission to change it.
[deleted]

Posted: 2012-02-07 23:15
Sri Lzlep No pun intended.
I understand your point.


Posted: 2012-02-08 20:42
This topic is very interesting, before my I pad was stolen, I used a app on that quite regularly. It seemed, that the further down the word tree that I traveled, it was less frequent to hear some of the newly introduced letters. Obviously, I found myself, using other methods to try and cram on new letters. To be honest, I think that, perhaps, this takes away from the actual learning intent of the kock method and, from the reason why Morse has its own particular structure.

In any laungage or dilect some letters are used more frequently than others. However, morse, tends to build subsequent letters on previous, which makes some sense. But, languages are not artificially designed as Morse was.

Another perspective on this, is that there can always be found order from disorder. Much of te wo


Posted: 2012-02-08 20:48
slateblue:
This topic is very interesting, before my I pad was stolen, I used a app on that quite regularly. It seemed, that the further down the word tree that I traveled, it was less frequent to hear some of the newly introduced letters. Obviously, I found myself, using other methods to try and cram on new letters. To be honest, I think that, perhaps, this takes away from the actual learning intent of the kock method and, from the reason why Morse has its own particular structure.

In any laungage or dilect some letters are used more frequently than others. However, morse, tends to build subsequent letters on previous, which makes some sense. But, languages are not artificially designed as Morse was.

Another perspective on this, is that there can always be found order from disorder. Much of te wo Post awaiting moderator approval.


I will finish what I started.....much of the work that Alun Turin did, after the war, was on order growing from chaos. Sometimes, as I listen to Morse, I think about the manbreolt set, number theory and cominatronics, CKn:-) forgive me for errors....but this part of learning Morse is really fascinating.


Posted: 2012-04-01 23:38
Izlep, just found this older thread. I'm with you on the lesson generation algorithm. I'd like to combine it with a few other mods and suggest it to Fabian as an upgrade.

I'd add more accurate effective wpm calcs (easier with a known distribution brought by shuffled list of predictable characters) and also slightly different tones on dits and dahs for newer characters (something Koch found to be useful for his students).

I'm happy to suggest the code for this in Perl, PHP or C.

I love the site, and would rather help improve it than go off piste with my own programme.


Posted: 2012-04-03 21:11
"Just learn Morse code" Has a very simple way to increase frequency of certain letters:

In menu Source->Selected Characters entering "abcd"will give equal weight to each letter. Entering "abbcd" will increase the frequency of letter "b"

Maybe worth a try.

Gerd.


Posted: 2012-04-20 16:56
I suppose another approach would go something like this. In each lesson:

1) Start with all characters at a pre-defined "error level". The new character would be (say) 50, and previous characters could either start at pre-defined levels, or use values from a previous lesson.

2) Produce random characters weighted by each character's current "error level".

3) At "Check Result" stage adjust each character's "error level", reducing it for each correctly read character and increasing it for each incorrectly read character, but cap the range of "error level" so it never drops to zero, nor exceeds (say) 100

Repeat steps 2 and 3 for each attempt at the lesson.


Posted: 2012-04-20 18:29
lzlep excuse me, I try to understand what you proposed, but I did not understand. My fault, I am sure.

What is a predefined error level?
The new character 50? What 50, 50 % error level?
or hex50 (=P) How can a new character be (say) 50% error level? That depends on you not on the character. How do you measure?

What happens? Suppose new character is A, file sents AAAAAAAA. what do you mean by 50% error level? ABADAEAC copied?

I get the idea that you propose that the characters you copy wrong, must be repeated more frequently.

Why not type your own text file, put it in text to CW for obtaining a MP3 file, copy that and compare your result with the original text file?

Do it repeatedly (for a week) with the SAME FILE in PLAIN TEXT till you copy it solid. After that take another file 5 minutes long same speed, till you copy that solid.

May be 2 wpm, because you now all the characters from Morse Machine.

When you reach 4 wpm, go over to the ARRL 5 wpm sources wit accompanied tex files.

Also exercise with ARRL, by downloading text 5wpm , and reading the text simultaneous with the morse sound files.


Posted: 2012-04-21 13:00
50? It was just a random weighting suggestion. The point is to try to track which characters the pupil is having trouble with, and send them a bit more often than others. This doesn't happen with the current Koch lessons, so they're less effective than they might be.

The Koch lessons are scored. A table is produced. Correct letters are green. Incorrect letters are red. Half the work's clearly already done, or how else would the colouring be happening.

The point of this thread has been to suggest improvements that might be made to the Koch lessons on this site. Sure, individuals can work around things other ways, but improvements to the site benefit all users.

The problems, from a pupil's point of view, with constructing files yourself are:

1) The pupil already knows the answer before the test.
2) The system isn't set up to check whether the pupil's read the sent text correctly.

I've tried the ARRL's files, but they're at 750Hz, which is quite painful to listen to.


Posted: 2012-04-21 15:27
Listening to Koch lessons, is a real disaster. The timing is far from OK and, the text is random, which make no sense.

So my proposal was to listen to the ARRL 5 wpm, because the text has sense, and tou can simulatneously read the accompanying textfile.

It is not an objection but an advantage to listen to the same file and decode it. Until you know exactly what is coming by heart, and even then, listening to a word that you know will pop up, is easier than decoding an unknow word.

Furthermore you get used to copy by head at that way.

Tone 750 Hz can be changed when you put the MP3 file in your transmitter and receive it with the receiver offset by RIT control, or what have you.

Or save it as a wav file, change the sample rate, The speed and the tone are changed simultaneously. You as a programmer will know how to do that, find the structure of the RIFF header on internet.

73


Posted: 2012-04-22 11:26
Much simpler to drop text into this site's "Convert text" option than to mess about re-pitching ARRL's files.

From an amateur's point of view, QSOs with call signs, Q-codes, and the rest would make better practice material than plain text. At least there's a chance to hear the less common characters in call signs.

Random characters at least have the advantage that the frequency of less well known characters can be increased to give a pupil more chances to hear them...

...and anyway, the main point of this thread was to suggest changes that could be made to improve this site, not to send people elsewhere.


Posted: 2012-04-30 17:10
Oooops! Now I'm experiencing the opposit problem. I'm nomore able to decode the "K".
Is there any option to switch off to go back to initial random system and get all characters with same frequency? Thanks


Posted: 2012-04-30 20:35

Bwa ha ha ha. Be careful of what you wish for; you may just get it! This program is very cool. Sometimes, I get lots of numbers and few letters. Other times I get lots of letters and few numbers. So strange. Yet it works over time. I join so many others in saying Thank you very much for this set of programs. Plain text is good for a practice run for qso's but to learn a letter it is better to have random chars. Because one has no idea what is coming next. With text one sort of has a clue what is coming next.

[b][quote=lzlep]50? It was just a random weighting suggestion. The point is to try to track which characters the pupil is having trouble with, and send them a bit more often than others. This doesn't happen with the current Koch lessons, so they're less effective than they might be. [/b]

This is an interesting idea. The program becomes self-learning for each student? A history of each students progress takes more resources.


Posted: 2012-04-30 21:03
tech25:
A history of each students progress takes more resources.


A full history would be rather resource-heavy, but it mightn't take too much to store a rough level (a small integer, or maybe even only a byte per character) indicating how well-learned a character is. Morse Machine already seems to do something like this.


Posted: 2012-05-02 12:15
Stats are shown in morse machine, lessons don't show them. I would love to see LCWO keeping stats for each character and adjusting frequency of them in order to level the results... But I guess I'm asking too much...
C'mon Fabian... don't be lazy... Ah ah ah
Just joking.
When I need to practice letter "K" I logo out, log in as "test" and switch to lesson 10. Character K is still sent in a reasonable quantity.
This site is amazing... now passed to lesson 21.
73
Riccardo


Posted: 2012-05-04 10:42
Character K is now beeing sent in a bigger quantity. Random or anything adjusted?

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