Polar APT

Most members start by receiving images from the `Polar orbiting satellites', which transmit Automatic Picture Transmission (APT) signals in the 137MHz band. Current satellites include the American NOAA series and Russian Meteor or Sich series. These tend to be sun-synchronous, with two orbits passing at or near overhead at the same times each day, 12 hours apart. APT resolution is about 4km per pixel and two channels are usually transmitted, Visible and Infra Red.

High Resolution Picture Transmissions (HRPT and CHRPT)

For the really keen and requiring either more experience in construction or a bit more savings, there are the highest resolution images available, namely HRPT or CHRPT. These transmission are from the Polar Orbitting satellites, about 1.7 GHz, and comprise either 5 (HRPT) or 10 channels (Chinese HRPT) of spectral information, giving resolution down to 1.1km pixels. It is necessary to track the satellite with your antenna and image files can be as large as 120MB.

Meteosat second Generation (MSG)

Meteosat Second Generation (MSG) consists of a series of four geostationary meteorological satellites, along with ground-based infrastructure, that will operate consecutively until 2020. The MSG satellites carry an impressive pair of instruments, the Spinning Enhanced Visible and InfraRed Imager (SEVIRI), which has the capacity to observe the Earth in 12 spectral channels and provide image data which is core to operational forecasting needs, and the Geostationary Earth Radiation Budget (GERB) instrument supporting climate studies.