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I've been studying for my amateur radio license recently, and this article is a great introduction to the basics. But really, if you want to get your hands dirty with some practical electronics, and also want to be able to communicate without relying much on nearby infrastructure, amateur radio is a great hobby.
Do yourself a favor and study for both your technician and general at the same time (I’m assuming you live in the US). HF is exponentially more fun than just VHF/UHF.
I tend to prefer these visual and intuitive explanations to the mathematically based ones usually given in lectures. The "open capacitor" example was something I hadn't thought of before.
…(scroll)…
> The identity for cos(α + β) can be trivially extended to cos(α - β), because subtraction is the same as adding a negative number:
…(scroll)…
> From the formula we derived earlier on, the result of this multiplication necessarily indistinguishable from the superposition of two symmetrical sinusoidal transmissions offset from a by ± b, so AM signals take up bandwidth just the same as any other modulation scheme.
Earlier quoted context omitted.
Do yourself a favor and study for both your technician and general at the same time (I’m assuming you live in the US). HF is exponentially more fun than just VHF/UHF.
it’s stuff like this that make me wish i lived in the US. i have to memorise a long questionnaire in german if i want to get my license
> In today’s article, I’m hoping to provide an introduction to radio that’s free of ham jargon and advanced math …(scroll)… > The identity for cos(α + β) can be trivially extended to cos(α - β), because subtraction is the same as adding a negative number: …(scroll)… > From the formula we derived earlier on, the result of this multiplication necessarily indistinguishable from the superposition of two symmetrical sinus…
> In today’s article, I’m hoping to provide an introduction to radio that’s free of ham jargon and advanced math …(scroll)… > The identity for cos(α + β) can be trivially extended to cos(α - β), because subtraction is the same as adding a negative number: …(scroll)… > From the formula we derived earlier on, the result of this multiplication necessarily indistinguishable from the superposition of two symmetrical sinus…
My uncle who's been building his own radios for over 60 years, tried to explain to me how antennas work, and even to him it comes down to "black magic".
I'm told the way they work is not really intuitive, so you just have to math it out.
Maybe I should have gotten an EE degree.
Imagine a circuit. Like a flashlight. The electrons flow from the battery to the lightbulb and back. It’s like a race track. They proceed in an orderly fashion.
There are some other electrical components. If you hook them up in just the right way, you get something called an LRC circuit. The electrons don’t flow in an orderly way now. They go back-and-forth. In spurts and fits. You’re making them wiggle. There are some very nice equations that allow you to specify exactly how much and how fast the wiggling is.
One cool thing about a circuit with wiggling electrons is that if you put some wires close by those electrons will also start wiggling.
This is called radio.
EDIT: I am offended that you guys think my awesome explanation is from GenAI. Imagine a circuit. Like a flashlight. The electrons flow from the battery to the lightbulb and back. It’s like a race track. They proceed in an orderly fashion. There are some other electrical components. If you hook them up in just the right way, you get something called an LRC circuit. The electrons don’t flow in an orderly way now. They…
> In today’s article, I’m hoping to provide an introduction to radio that’s free of ham jargon and advanced math …(scroll)… > The identity for cos(α + β) can be trivially extended to cos(α - β), because subtraction is the same as adding a negative number: …(scroll)… > From the formula we derived earlier on, the result of this multiplication necessarily indistinguishable from the superposition of two symmetrical sinus…
I got my amateur radio license last year, and this is precisely why I haven't been able to do much with it: seemingly all the guides, even the license study materials, use vocabulary I'm not familiar with. I have two CS degrees and a solid foundation in math, but I can't understand how radios work because of vocabulary more than the math. My uncle who's been building his own radios for over 60 years, tried to explain…
But yeah, black magic is right!