Foundations of Amateur Radio

For some time I've been explaining how some of the internal workings of a Software Defined Radio operate with a view to getting into the nitty gritty of the why and the how. This exploration is happening within the context of a world where there are countless choices for selecting a radio to match your budget. Increasingly that selection process starts with a simple question: Should I purchase a Software Defined Radio or a traditional radio?

This is not a new question, previously it may have been: Should I select a radio with transistors or one with valves? Presumably the same happened when your ancestors faced a choice to buy a new car or update their horse and carriage. Of course I'm being flippant, but the point stands, as things evolve, choices change. Today we don't know what comes after the Software Defined Radio that we currently know, but it's likely to force the same selection on future generations of radio amateurs.

So, if you're in the market for a new radio, what things should you consider in your selection?

SDR is becoming pervasive, that is, the more you look, the more you'll find. Much like transistors overtook valves, not because they're better, but because there's a smaller component count and related price advantage.

SDR come in all forms, from nondescript black boxes to a traditional radio form factor and everything in-between.

If you choose a black box model SDR, there are tools around that allow you to use external controllers to provide knobs and buttons. These external controllers might be a fully-fledged radio head, or it might be using an external USB connected knob to change the frequency, or you might integrate your solution with a DJ Console, a big panel with lots of knobs, sliders and dials, repurposed as a user interface for your radio.

The software behind most SDR platforms appears to continuously be in a state of rapid development. This means that every update potentially gives you more functionality. Of course the opposite is also true, things break, get taken away, get redeveloped, in ways that may be unexpected or unwanted.

In my opinion, there's an awful lot of crap software around, attempting to use a computer screen to emulate a physical environment, forcing you to use a mouse to turn a knob, or slide a slider. It's getting better, but so far I've not seen a single solution that does this all well. That's not to say that there aren't any innovative things happening either. For example, something I've mentionned in the past, is the user interface for the diversity receive function inside PowerSDR. You set the phase angle and the strength by pulling on a line inside a circle.

There's plenty of open source software around, and functionally it's pretty good. Fortunately Windows is not your only option, Mac OS and Linux provide many opportunities.

Traditional radios have not finished, nor are they likely to go the way of the Dodo anytime soon, but while people are getting excited, you can pick up bargains from those migrating away from traditional radio to SDR.

If your selection is based on using a computer or not, there's things to use your computer for with a traditional radio, numerous and growing digital modes and other cool stuff to get your teeth into.

I should mention that there are radios about that are both traditional and SDR, so you can have the best (or worst) of both.

My recommendation is to set a budget and see what that buys you. Regardless of what you end up with, your requirements will evolve.

I'm Onno VK6FLAB