Types of Ground Station
There are two main types of ground station. The first is a simple way to dip your toes into the SatNOGS pool. It uses simple parts and is relatively quick to set up. The second involves more work but can provide better results. It is recommended that newcommers with little or no experience go for the simpler fixed type to get themselves aquainted, some users have put up fixed stations to test their system up whilst building up the steerable station.
Fixed or Non Rotator Ground Station
A minimal station which consists of a way to connect to the network (typically a Raspberry Pi) a radio receiver (typically a RTL-SDR simple software defined radio) and an antenna (typically a Turnstile or eggbeater type antenna).
Whilst this might be considered a simple station they are more than capable of being used to receive Voice, CW or Data from satellites. The biggest choice is whether to go for a VHF (2m band) or UHF (70cm band) antenna.
There may be a need for additional hardware that helps remove local noise, such as band pass filters for the 88-108Mhz broadcast band or Low Noise Amplifiers (LNA's) but these are generally found out once the ground station has been set up and is in the testing phase.
Steerable or Rotator Ground Station
Originally the defining part of the SatNOGS network was the home built rotator. It consists of a combination of 3d printed parts or commercial off the shelf items used in a way that lets the antennas follow a satellite. This type of build is more complex but will give better results.
There is no reason why you can't use the same receiver and computer combination to do the hard work but this option allows you to add in additional antennas to cover both the 2m and 70cm bands.
If more than one band is being served by a single receiver then additional hardware such as a diplexer will be required. Further information can be found at the rotators page.
Typically, the receiver consists of an RTL-SDR dongle and a Raspberry Pi. The Raspberry Pi has an Internet connection to the SatNOGS network. The RTL-SDR dongle connects to the antenna. Further information can be found in the radio page.
The type of antenna used depends on the ground station. Different satellites will have different uplinks and downlinks and the choice of antenna will affect the observation. See the Antennas page for typical ground station set ups in detail. There are several main types being used with Turstiles and Eggbeaters being common with Fixed ground stations and Yagi, Helical and Quad antennas being commonly found on Steerable ground stations