Bald Yak 21: When you need to travel to Pluto and back

Foundations of Amateur Radio

I recently expressed the notion of using a PlutoSDR as a replacement for an oscilloscope, a spectrum analyser, and perhaps even a vector network analyser. I can add signal generator to that list and you get the notion that this one device might replace a bunch of tools in your shack.

So .. I set out to come up with a minimum viable product to see what I might discover.

There are days when you get out of bed with a spring in your step, only to end the day exhausted and thoroughly defeated. Given the chance, the next day, you get out of bed and try again.

Fortunately for me, I have a full head of hair and my yak shaving barely made a dent and as a bonus, I learnt something, which is always nice.

The short version is that you should use a USB Y-adaptor or splitter to ensure that your PlutoSDR has enough juice to power a USB Ethernet dongle.

That statement alone is worth at least a combined fifteen hours of Yak Shaving.

Without this turning into a PlutoSDR specific troubleshooting saga .. for reasons I don't understand, plugging the power supply into the Pluto power socket and a USB Ethernet dongle into the accessory port doesn't work, but plugging both into a Y-adaptor and that into the accessory port makes all the blinkenlights work, even those on your network switch. As I said, fifteen hours.

So, what does this buy me, other than an appreciation for subtlety? It gives me network access to my PlutoSDR, which makes it possible to connect to it using GNU Radio running on a different computer, which then allows me to experiment.

Before starting this side-quest into connecting to my Pluto, I went on the hunt for some example code. Jon Kraft, who is a senior staff Field Applications Engineer at Analog Devices, whom I came across first on YouTube, where he's been playing with beam-forming and other nifty RF phenomena, also has a GitHub repository with some PlutoSDR examples for use with GNU Radio.

These examples are pretty straight forward, essentially connecting to a PlutoSDR, setting the centre frequency and extracting a bunch of RF and visualising it. Essentially what you'd want in some testing gear.

After playing around for a bit with Jon's examples, I'm able to see radio spectrum, across the network, on my screen, using GNU Radio.