OnAirSatellite & navigation · Experimental
Decode Meteor-M LRPT with an SDR
OnAir receives Meteor-M LRPT. Meteor-M N2-3 / N2-4 weather pictures on 137.1 / 137.9 MHz (LRPT: OQPSK or QPSK, 72 or 80 ksym/s): the MSU-MR channels and a colour composite grow line by line during the pass, saved as PNG.
What Meteor-M LRPT is
Meteor-M is a Russian weather satellite series. Its LRPT downlink on 137 MHz sends live weather pictures that you can receive with a small antenna during each pass.
Frequencies and where it is used
Meteor-M N2-3 / N2-4 weather pictures on 137.100 / 137.900 MHz: OQPSK 72k (differential), QPSK 72k or the interleaved OQPSK 80k mode, Viterbi, Reed-Solomon, CCSDS packets, MSU-MR JPEG-like strips.
In OnAir the tuning shortcut is Weather pictures, 137 MHz; you can enter any frequency your radio reaches.
What OnAir shows for Meteor-M LRPT
The picture grows line by line during the pass: channels 1 - 6 and a colour composite (123 by day, 125 at night), Save PNG; View > Passes starts it at AOS and follows the Doppler. Checked only against the built-in test signal so far: no off-air recording yet.
This receiver is built from the published specification and checked end to end on simulated signals. It has had little or no testing on real transmissions yet, so reports and recordings on Discord are welcome.
Which radio you need
Any radio that tunes this range works. An RTL-SDR covers roughly 24 MHz to 1.7 GHz, and every other radio in the radio guide reaches it too. Antenna height and a clear view of the transmitter matter most.
Questions about Meteor-M LRPT
Can I decode Meteor-M LRPT with an RTL-SDR?
Usually yes for narrowband signals, as an RTL-SDR tunes roughly 24 MHz to 1.7 GHz at up to about 2.4 Msps. Wide signals such as TV channels need a faster radio, and OnAir says next to the source what the selected radio can do.
Is it legal to receive Meteor-M LRPT?
Receiving satellite downlinks is generally legal. Encrypted or spread content is not decoded, and voice codecs that are patented are not shipped with OnAir.
Can I try Meteor-M LRPT in OnAir without a radio?
Yes. Most modes include a built-in synthetic test signal, so you can open the screen and try the controls before you own a radio.
Try it without a radio
OnAir includes built-in synthetic test signals for most modes, so you can open this screen, see the layout and try the controls before you own a radio. The Tour button walks you through the app.