RTL-SDR Radio Adventures
The RTL-SDR is a TV Dongle that is used to pick up digital TV. Using a feature on the chip called I/Q sampling, it is possible to tune to pretty much any frequency between 22mhz and 1200mhz. With a filter tuning to frequencies lower than 22mhz is also possible.
During my attempts, I have used everything between paperclip, to a long wire, to dipole antennas. I dealt with weird interference patterns that made tuning into weaker signals hard.
Interference within 1090MHZ while looking for aircraft transponders
For Aircraft Transponders I used a dipole with the current length for the frequency. I didn’t do any calculations as the majority of people have found two 7.5cm antennae in a dipole configuration give good results.
This write up is in progress.
Picking up passive aircraft ADS-B Transponder signals
Listening to ATC/Air Traffic.
Android support for SDR Driver
Data collected from a 11.5cm vertical dipole outside my house in San Diego.
Created using modified code from https://github.com/JorgeGT/PlotRTL1090.