Over on YouTube we've found an interesting project by RingingResonance where he's created a simulated traditional radar scope using a real analog radar scope tube, and ADS-B data gathered from an RTL-SDR running dump1090 on a Raspberry Pi 3B.

The project uses a real radar scope tube which is controlled by SPI signals sent from the Raspberry Pi into a DAC, which is in turn connected to the analog radar scope. RingingResonance has uploaded the open source code to GitHub. He notes that the code currently pushes the Raspberry Pi 3 to it's limits, so the sweep speed is limited.