OnAir

Receive weather satellite images with OnAir

Pictures grow line by line while the satellite passes overhead.

Which satellites#

ModeWhereYou need
Meteor-M LRPTMeteor-M N2-3 / N2-4 on 137.100 / 137.900 MHzan antenna for 137 MHz and a radio that tunes it
GOES HRITGOES-16 / 18 / 19 on 1694.1 MHza dish (about 1 m, or a grid antenna) with an LNA and filter at the feed
Elektro-LElektro-L N3 / N4 / N5 around 1691 MHza dish with an LNA
HRPT / AHRPTMetOp-B / -C AHRPT on 1701.3 MHza dish (1 m or more) that follows the satellite, an LNA at the feed and a fast radio (4 Msps or more; not an RTL-SDR)

NOAA's own HRPT is listed in HRPT / AHRPT, but NOAA-15, 18 and 19 are retired.

Steps for Meteor-M LRPT#

  1. Set your position (setup wizard or the map) so passes can be computed.
  2. Open View > Passes, the satellite pass planner. It uses current orbital data (TLE): download a list, add your own custom TLE source, or use the Keplerpass button. See Privacy for which servers those are.
  3. Choose Meteor-M LRPT (group Weather and science). The default is 137.9 MHz.
  4. Let the pass planner start the receiver at AOS (acquisition of signal). It follows the Doppler shift, and the carrier hand-over tracks about ±3.5 kHz of it (0.2.6).
  5. Watch the picture grow line by line: channels 1 to 6 and a colour composite (123 by day, 125 at night). Press Save PNG; there are contrast stretch, thermal colours, brighten and auto-save options (0.2.6).
  6. The pass planner can also record the radio's IQ during the pass, as Record IQ does.

Notes#

  • Real frames pass Reed-Solomon since 0.2.5 (issue 79); GitHub issue 79 (Meteor M2-3 LRPT) is still open, so recordings of real passes are welcome.
  • A rotator can point a dish: see antenna rotator.