Weather Satellite Decoder

ALPHA: Weather Satellite capture is experimental and may fail depending on SatDump version, SDR driver support, and pass conditions.

Receive and decode Meteor LRPT weather imagery. Uses SatDump for live SDR capture and image processing, and also shows Meteor imagery produced by the ground-station scheduler.

Satellite

Select Satellite

Gain (dB)

Bias-T (power LNA)

Antenna Guide

137 MHz band — your stock SDR antenna will NOT work.

Weather satellites transmit at 137.1–137.9 MHz. The quarter-wave at this frequency is ~53 cm, far longer than the small telescopic antenna shipped with most SDRs (tuned for ~1 GHz). You need a purpose-built antenna.

V-Dipole (Easiest — ~$5)

   coax to SDR
       |
    ===+===  feed point
   /       \
  /  120    \
 /           \
/     deg     \
53.4cm    53.4cm

Element length: 53.4 cm each (quarter wavelength at 137 MHz)
Angle: 120° between elements (not 180°)
Material: Any stiff wire, coat hanger, or copper rod
Orientation: Lay flat or tilt 30° toward expected pass direction
Polarization: The 120° angle gives partial RHCP match to satellite signal
Connection: Solder elements to coax center + shield, connect to SDR via SMA

Best starter antenna. Good enough for a clean Meteor LRPT pass when the satellite gets high overhead.

Turnstile / Crossed Dipole (~$10-15)

       53.4cm
    <--------->
    ====+====  dipole 1
        |
    ====+====  dipole 2
    <--------->
     90 deg rotated
     + reflector below

Elements: Two crossed dipoles, each 53.4 cm per side (4 elements total)
Angle: 90° between the two dipole pairs
Phasing: Feed dipole 2 with a 90° delay (quarter-wave coax section ~37 cm of RG-58)
Reflector: Place ~52 cm below elements (ground plane or wire grid)
Polarization: Circular (RHCP) — matches satellite transmission

Better than V-dipole. The reflector rejects ground noise and the RHCP phasing matches the satellite signal.

QFH — Quadrifilar Helix (Best — ~$20-30)

     ___
    /   \   two helix loops
   |  |  |  twisted 90 deg
   |  |  |  around a mast
    \___/
      |
    coax

Design: Two bifilar helical loops, offset 90°
Material: Copper pipe (10mm), copper wire, or coax outer shield
Total height: ~46 cm (for 137 MHz)
Loop dimensions: Use a QFH calculator for exact bending measurements
Polarization: True RHCP omnidirectional — ideal for overhead satellite passes
Gain pattern: Hemispherical upward coverage, rejects ground interference

Gold standard for weather satellite reception. No tracking needed — covers the whole sky.

Placement & LNA

Location: OUTDOORS with clear sky view is critical. Roof/balcony/open field.
Height: Higher is better but not critical — clear horizon line matters more
Antenna up: Point the antenna straight UP (zenith) for best overhead coverage
Avoid: Metal roofs, power lines, buildings blocking the sky
Coax length: Keep short (<10m). Signal loss at 137 MHz is ~3 dB per 10m of RG-58
LNA: Mount at the antenna feed point, NOT at the SDR end. Recommended: a low-noise 137 MHz filtered LNA near the antenna feed point
Bias-T: Enable the Bias-T checkbox above if your LNA is powered via the coax from the SDR

Quick Reference

Wavelength (137 MHz)	218.8 cm
Quarter wave (element length)	53.4 cm
Best pass elevation	> 30°
Typical pass duration	10-15 min
Polarization	RHCP
Meteor (LRPT) bandwidth	~140 kHz

Test Decode (File) ▼

Decode a pre-recorded Meteor IQ file without SDR hardware. Shared ground-station recordings are also accepted by the backend.

Satellite

File Path (server-side)

Sample Rate

Auto-Scheduler

Automatically capture satellite passes based on predictions. Set your location above and toggle AUTO in the strip bar.

Enable Auto-Capture

Disabled

Debug / Test

Load sample pass data and console output to test the UI without an SDR or live satellite pass.

Resources

SatDump Documentation Meteor Reception Guide