Now that everything is working (hopefully!), we can proceed to customising the display.
The majority of the aircraft symbols seen will be yellow, but various colours can be assigned and labels expanded or reduced to individual preference. Additional colours are also used – for example expiring aircraft are orange and Mlat white. You may also catch an aircraft with blue concentric circles radiating from time to time – these aircraft are squawking ident usually as a result of a squawk change.
To change these parameters we need to open up Chart Options (menu or easier via the spanner symbol). Initially the options seem bewildering, however its all quite straightforward, nevertheless I’d recommend changing a few things at a time and re-checking the display to see if its appropriate to your needs.
So you are in receipt of a shiny new Realtek RTL2832U+R820T SDR dongle and I understand the first thing you want to do is start decoding ADS-B, ACARS or some other exotic data format. Maybe you just want to listen in to some local comms? Well we really need to get some software loaded up.
There are two popular SDR tuning programs and both are freeware: SDR# (SDRSharp) and HDSDR. I’ve tried both, but highly recommend SDR# as its more user friendly – especially for newcomers so we’ll stick with that.
There are numerous SDR# versions available (stable/nightly builds) and a degree of experimentation is required to get the program up and running. Installation worked flawlessly on one PC but was a total nightmare on another. Eventually I got it working on both (funnily identical Windows XP platforms!). SDR# requires .NET Framework to be installed prior to running and the problems I had installing SDR# on my laptop was because I had 4.5 installed and not 3.5. To be on the safe side I ended up installing .NET Framework versions 1.0, 2.0, 3.5 and 4.5 (overkill or what?!).
I had my first real taste of radio decoding back in the 90’s. Things were a little different then though. For starters you needed a scanner or HF radio (or both), a demodulator (from Pervisell), leads to connect the radio audio output to a computer soundcard and of course software (or just plain old DOS) and a PC to process everything. At the time I had a subscription to Shortwave Magazine (sadly no longer in print) and the decode section was a godsend.
Each decoding practice had different protocols and often things didn’t work out as planned. Many hours (or days) were spent tinkering with leads, interface settings (bloody COM ports!) and antenna locations. If you were unlucky the Windows blue screen of death would make an appearance every now and again!