Propagation is everywhere!

Foundations of Amateur Radio

Recently I talked about making a propagation map in your mind by listening to the various NCDXF beacons across the globe on various HF bands. You're not limited to listening to a beacon to learn what propagation is like.

If I tell you that listening to a band gives you an indication on what's going on, you're likely to respond with: "Duh".

But what if I suggest that instead of listening to a DX station running a pile-up, you instead listen to the stations calling?

Back in January 2014, episode 133, when this series was still called "What use is an F-call?", I explained what "Listening 10-up" means and how you operate in a so-called split mode. As you might recall, working split is about dealing with the phenomenon that a weak DX station working in some desirable location is likely to be overwhelmed by stronger signals, to the point of no longer being heard. It's a good skill to learn and you should try and work both sides, being the station calling a DX, but also being the one getting swamped.

As I said, normally you're the one calling the DX station and you don't particularly care about the other stations swamping the band.

What if you did?

What if you used their signals to figure out where propagation was happening? If you did that, you could perhaps point your antenna in the correct direction, or specifically focus on calling for stations in that area, or listen out for stations in that region in other parts of the band.

The thing is, propagation doesn't care what the signal is. As long as you can decode it in what ever way you prefer, Mark I ear-drum, or some fancy decoder, it doesn't matter. If you can hear the signal, it means it's getting from them to you.

I should note a word of caution here.

It's taken me several years to realise that I could often hear many stations that had no chance of hearing me. I'd crank up the volume on the radio, listen out for anything and try to work what I heard. Sometimes you get a great result, and you shouldn't discount those, but often all I got for my trouble is a sore head from decoding mush.

What I learned, especially as a low power operator - I use 5 Watts - if the other station isn't coming in with a reasonable signal strength, S5 or higher, then there's little point.

There is a concept of reciprocity. The idea is that if you can hear them, you can work them. For some power levels that might actually be true, but for the rest of us, a fine grain of salt should be added to the mix. Before you start in on me telling me I'm wrong, perhaps consider the variations in local environment, antenna differences, not to mention variation in the Ionosphere or alligators, all mouth and no ears running several kilowatts.

The take-away in all this should be that propagation is everywhere. You can use it to hunt for likely contenders and no signal on the band should be ignored as a potential source of propagation information.

One final thought. You can also reverse this. Turn on a web based receiver in some desirable part of the world, pick a frequency and then using your radio, call CQ and see if you can hear yourself across the web.

I'm Onno VK6FLAB