Unschooling and Ham Radio

Here's another example of how unschooling works. You're sitting around minding your own business, when a kid walks by and asks what USB is. They don't mean Universal Serial Bus, they mean Upper Sideband. They noticed it on the software defined radio screen. So, you wind up explaining about mixers. Not a whole lot, just enough. You explain that when you modulate you create the carrier signal (14 or so megahertz in our case) as well as a modulated signal above the carrier and a modulated signal below the carrier.

These two signals carry the voice, data, or whatever you modulated with. You then explain that the AM 9 band shortwave doesn't pick up Morse code super well because it wants to hear both sidebands and Morse code (CW) tends to act like a single sideband. They wander off. You'll ge the opportunity to cover more details later.

A few hours later, you find out they can practice Morse code on the radio while you operate the station as long as you're present. You read this from Part 97 of the FCC rules, (the part about ham radio.) This seems cool. They want to study for the ham radio exam, and so they do:

And there's the mixer you were discussing earlier:

You've been hoping they'll pick algebra back up for the last several months. Neither you or the kid has put tht much of a concerted effort into it. Then, because of this, it just happens:

Later on you're discussing tropospheric ducting.

(Excellent picture from the site linked above by VK3FS)

Looking at that page, I'm even more inclined to think our band shutdowns in the morning, right when the sun peers over the hill are induced by sudden temperature inversions. I wonder if there's a way to measure that? Anyway.

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