[amsat-bb] BY70-1 FM Transponder Active Over North America

Paul Stoetzer n8hm at arrl.net
Wed Dec 28 18:09:16 UTC 2016

The FM transponder was active on BY70-1 for the passes over North
America this morning. K4KDR reported hearing my call on the pass
around 1540 UTC, but I did not hear myself. On the 1709 UTC pass, I
worked AC0RA and heard AA5PK.

The signal is strong, but the uplink seems to require precise Doppler
tuning. I was only able to get in cleanly when tuning for Doppler,
starting at around 145.917 MHz near AOS and tuning up to 145.923 MHz
near LOS. An FM only radio with only 5 kHz steps may not work well for
accessing this transponder.

There was also a clear SDR delay on the downlink signal which makes
things interesting and it seems to require a bit of power to break the
squelch. I was using about 30 watts on this pass.

Equipment used was 2 FT-817s, a High Sierra Microwave preamp, a
Microset VUR-30 amplifier, and an Alaskan Arrow antenna with the top
section removed (8 elements on 70 cm and 3 elements on 2 m)

Unfortunately, the satellite's life is destined to be quite short due
to the incorrect orbital insertion with a very low perigee. The
2016-083A keps from CelesTrak's TLE-NEW.txt file seemed pretty

I have posted a recording of the pass. Skip ahead to about 2:35 of
this recording:



Paul, N8HM

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