Foundations of Amateur Radio The evolution of Amateur Radio is a constantly changing landscape. I've previously described the transition from spark-gap to surface-mount and the ongoing progression of inventiveness that brings this amazing hobby together with the leading edge of science and technology. If you think of software defined radio as a linear increment on the radio scale you'll end up where we see some of the manufacturers today are placing their bets. You'll find a radio that has knobs and buttons like a traditional radio, but behind the scenes there is a computer and a new way of accessing the radio spectrum. A little further along the scale is the proverbial black-box, often with a single button to power it on, a few connectors for antennas and a network connection to get information to a computer. The software on the computer often attempts to resemble a traditional radio with similar controls and the combination of the box and the computer with the software running makes for an Amateur station. If you have no rules for how the user must interact with the radio, you might come up with interactive waterfall charts that display the radio spectrum as a graph, showing frequency along the horizontal axis, time across the vertical axis and colour as a measure of signal strength. Each of these experiences are attempting to achieve the same purpose, making the radio spectrum available to the station operator. If you completely decouple the concept of radio from this and look at the spectrum as a source of data, then processing that data, often in real-time, becomes less constrained by the limits of our current perceptions of how a radio works and moves into the realm of data science. To give you a concrete example, if you've scanned a photo on your computer and are confronted by little dots of dust, there is software available to remove that dust and re-create the image in much the same way as the original might have been. The process is called noise reduction. That same process could also be used to process radio spectrum, or audio. There are many concepts that exist outside radio that can be used in this new world. You could do live analysis of the bands, determine which signal had the best chance of getting to the intended recipient, you could decode information spread across multiple bands, with bandwidth use that could be measured in gigahertz, rather than kilohertz. With the limits of your mind as the only barrier, what other inventions might be arriving at our doorsteps in the near future? I'm Onno VK6FLAB