The other problem with this seems to be memory access speed in the Raspi. To do it right, or better, would be to use the SPI bus as it was meant to be used, IE: 8 bit data instead of forcing it to be 16 bit and making the CS change take too long, feed that into a custom circuit or FPGA that could buffer the data, and then either output directly to a custom DAC, or output to another SPI bus that is designed and dedicated to the LTC1662 DAC’s. “hacking” the Raspi’s SPI bus for this was fun and allows for simple hookup for anyone who wants to just feed the analog data straight into an oscilloscope in XY mode, or their own dedicated XY scope. Posted in Misc Hacks, Retrocomputing Tagged 5FP7, ads-b, dump1090, flight tracking, flyback, persistence, phosphor, radar, Radpberry Pi, sdr Post navigation And no, you’re not seeing things if you see two colors in the video below as helpfully explains, P7 is a cascade phosphor that initially emits a bright-blue light with some UV in it, which then charges up a long-persistence green phosphor.Įven though multicolored icons and satellite imagery may be more useful for flight tracking, we really like the simple retro look has managed to pull off here, not to mention the hackery needed to do it. The latitude and longitude of each plane within range - about 5 nautical miles - is translated to vector coordinates, and as the “radar” sweeps past the location, a pip lights up on the scope. ![]() ADS-B data comes from an SDR dongle using dump1090 running on a Raspberry Pi 3B. The software side has a lot going on as well. There’s also a lot going on with the X-Y deflection amps and beam intensity control. The tube needs about 7 kV for the anode, which is delivered via a homebrew power supply complete with a custom flyback transformer. ![]() As you can imagine, this project is pretty complex, starting with driving the 5FP7 CRT, a 5″ round-face tube with a long-persistence P7-type phosphor. ![]() To bring some of that old-school feel to his flight tracking, has been working on this ADS-B scope that uses a real radar CRT. But that was then now, flight tracking is as simple as pulling up a web page. Real-time flight data used to be something that was only available to air traffic controllers, hunched over radar scopes in darkened rooms watching the comings and goings of flights as glowing phosphor traces on their screens.
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