Frequencies, TLEs and Beacons

ELFIN-A transmits 9600 baud beacons on 437.450 MHz with the FCC experimental call sign - WJ2XNX. It is currently in “early orbit mode”, beaconing every 34 sec.

ELFIN-B transmits 9600 baud beacons on 437.475 MHz with the FCC experimental call sign - WJ2XOX. It is currently in “early orbit mode”, beaconing every 41 sec.

TLEs can be found on space-track.org. The norad catalog ID of ELFIN A is 43617 and ELFIN B 43616.

Beacon formats for both are available here with proper conversions included. 0x27 is our escape code for 0x93, 0x5e, and 0x27. If you have received any beacons, please report them to elfin@igpp.ucla.edu. DK3WN has made a beacon decoder available here: https://www.dk3wn.info/wp/digital/ (more info: https://www.dk3wn.info/wp/satelliten/elfin/). We aggregate data from the SatNogs DB as well, the dashboard and satellite observations can be found here for ELFIN A (https://db.satnogs.org/satellite/43617) and ELFIN B (https://db.satnogs.org/satellite/43616).

Both ELFIN satellites are healthy and operational. Huge thanks to all of the radio operators out there listening to us!

We currently transmit data downlinks at 9k6 baud rate over the East coast (Wallops Island) and over a StellarStation antenna in Tokyo at 9k6 as well, even though we have capability of transmitting at 19k2.

On September 16th, 2018 (1 day after launch) we decoded our first beacon from ELFIN-A. Please find the audio file and demodulated data below. Data demodulated using Direwolf on GFSK9k6.

On September 17th, 2022, ELFIN A’s orbit decayed to the point of reentry somewhere between 13:13 and 17:14 UTC. The final decoded transmission was by @JA1GDE at 13:13 UTC on 9/17/22. A pass over UCLA 4 hours later confirmed ELFIN A no longer existed.

On September 30th, 2022, ELFIN B had reentered. The last decoded transmission was over UCLA at around 5:20 UTC. A pass 11 hours later confirmed that ELB had deorbited.