Foundations of Amateur Radio

Radio Waves travel in straight lines. They go from point to point and that's it. Except that Radio Waves also reflect off certain surfaces, like light does.

So, Radio Waves travel in straight lines and they also reflect and that's it. Except that Radio Waves also change direction when they pass through some change of medium.

So, then, Radio Waves travel in straight lines and they also reflect and refract and that's it. Except that Radio Waves also bend when they encounter an obstacle or a slit.

So, ok that's it. Radio Waves travel in straight lines and they also reflect and refract and diffract and that's the end of it. Except that they turn slightly due to gravity when they pass by a large mass.

So, this phenomenon that we use in our hobby every time we key up a transmitter or listen to an off-air signal is doing much that is invisible. It bends and wobbles, bounces and shifts, reflects and refracts and somehow we still manage to make our signal get from here to there.

The reason I'm raising this at all is that all new entrants to the hobby often scratch their head when they start transmitting. Antennas and propagation aside, the humble hand-held portable radio, the walkie talkie, or handitalky, or whatever you call it, does some weird stuff.

Some people use it like a mobile phone, other talk into it like they're summoning the oracle, others wave it about and hover around metal doorways or hold it close to their body and walk about while they're talking.

I host a weekly radio net, you should check it out some day, Saturday Morning, 0:00 to 1:00 UTC, it's called F-troop and we get lots of different skill levels and experiences sharing stories and answering questions.

Many times we have amateurs who are using a hand-held and getting unexpected results.

This variable, fluid nature of radio waves is why this happens. Each tiny variation causes some effect and some outcome. Resulting in a wildly fluctuating signal that varies between loud and clear and inaudible and all steps in between. And that's not even talking about flat batteries or trying to talk through a hill to a local repeater.

My point is that radio waves are unpredictable. If you are using your radio in an unpredictable way while using an unpredictable medium like radio, then all bets are off.

Next time you key up your hand-held, spare a thought for what's happening between your antenna and mine.

I'm Onno VK6FLAB.