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Morse Code Amateur Radio Callsign Aliasing on the Reverse Beacon Network

 Listening to a recording of myself sending Morse code over the weekend, it finally occurred to me why KD0FNR is frquently aliased as KD0F by the Reverse Beacon Network: NR sounds a lot like the character '/'. The LCWO code practice site made it easy to tell you and show you:

First, listen to the entire KD0FNR callsign:



Now, listen to just NR:


And now, here's the character '/':

Hear the similarity? The RBN ignores characters after '/'. Thus, the 'slash' (that's really NR) is ignored, and the callsign KD0FNR truncates to KD0F.




Ham Radio and Unschooling

The middle kid, 10 year-old Mota, is mildly interested in ham radio and he's learning Morse code. He is however, very interseted in programming. Consequently, he's been working though an html5 game programming book. In the book, he's having to learn both html and JavaScript. Consequently, he knows what a div is, and he knows where his JavaScript code gets pulled into the web page. The next time we meet to program, I'll show him what blew out on this very web page!

When I tried to setup the three players above, initially, only one of them displayed. (To see the full html of this page including what is shown below, just press Ctrl+U. The html for embedding a player is:

    var m = new jscw();
    m.setWpm(20);
    m.setEff(18);
    m.setFreq(600);
    m.setText("nr");
    m.renderPlayer('player1', m);
where the referenced code is pulled in from 

https://lcwo.net/js/jscwlib.js

It took me more time than I'm making it seem here, but I finally realized that the first argument of m.renderPlayer('player1', m); refers to a div id:

this.renderPlayer = function(el, obj) {
            var el = document.getElementById(el);

So, when I added three bolierplate players to the page, they all were overlaid (at best) in the same div. I changed the names of the second two divs, passed the new names to their respective renderPlayer calls, and everything just worked.

I'll get to talk to the kid about it, and he'll get to see that the very same things he's using are occasionally hosing me up.




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