The antenna makes a helix shape and looks like it would be ... variety and range of antennas and how they appear internally. L band is from 1 GHz to 2 GHz, so signals and antennas get very strange ...

[Mark] had his eyes on the nice quadrifilar helical antenna used by the ... but in the end managed to get a working antenna with 40 dB gain in the L-band, and with the help of an RTL-SDR dongle ...