Given the abundance of satellites with UHF transmitters, I decided to trade the omni-directionality of a turnstile antenna for a bit more gain/directionality of a corner reflector for my UHF ground station.
The PDF attachment below shows a design of a UHF corner reflector antenna that’s very easy to build and turns out to give pretty good results. It can be built using standard materials and tools and seems to be quite forgiving to errors (i.e. no phasing lines).
weekend_antennas_4.pdf (165.5 KB)
Here’s a picture of my build (the VHF turnstile is in the background):
My antenna is pointed towards the South, and I tend to only select satellite passes that are visible in the Southern hemisphere. From 53 deg North, all ISS launched objects will pass through the beam for multiple consecutive passes, and typically polar/sun synchronous orbits have two good passes per day. This means I can basically fill an entire day’s worth of observations with back-to-back passes. See the past observations of CGBSAT-UHF to get an idea of how well it works. Note that I’m not using an LNA. A v3 RLT-SDR is connected via about 2 meters of RG-58.
I can highly recommend a corner reflector for the UHF band of a SatNOGS station.
