Information for radio amateur enthusiasts

One of the functions of GRBAlpha is also a digipeater with severall modes. The satellite carries a transciever called Cormorant NX-TRX4 on board. Robo Laszlo OM1LD, together with developers from Needronix s.r.o., is behind the develepoment of this transciever.

The basic information for receiving of satellite are:

    • Callsign: OM9GRB
    • Downlink frequency: 437.025 Mhz +/- Doppler shift
    • Modulation: GFSK, CW
    • Encoding: G3RUH 9k6 bd
    • Protocol: AX.25
    • Transmitting power: 1 W

Cormorant NX-TRX4 (Source:

Orbital parameters of GRBAlpha satellite

Preliminary orbital parameters after the separation from Fregat:

Semi-Major axis (km)a6920.3
Altitude of perigee (km)Нπ537.3
Altitude of apogee (km)561.4
Inclination (deg)i95.57
Longitude of the ascending node (deg)Ω73.55
Argument of perigee (deg)ω173.03
True anomaly (deg)ς123.16
Argument of latitude (deg)u296.18
Osculating period (h:min:s)Tosc1:35:29.3

And finally, the most important thing. Pre-flight TLE. These data are calculated based on preliminary parameters and may not be completely accurate. Once the actual location is obtained, they will be edited and you will then find corrected TLE here.

Updated TLE! Published on March 25, 2021.

1 47938U 21022G   21081.71325178 -.00000062  00000-0  00000+0 0  9992
2 47938  97.5867 345.5924 0019826 235.8986 123.9996 15.05343367    55

File with TLE data for download: GRBAlpha_TLE

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