BY70-1 FM transponder satellite

BY70-1 CubeSat

BY70-1 CubeSat

A CZ-2D rocket carrying the amateur radio FM transponder satellite BY70-1 was launched on Wednesday, December 28 at 03:23 UT.

Update: Paul Stoetzer N8HM reports working Wyatt Dirks AC0RA through the FM transponder during the 1709 UT pass on December 28. Paul says “Uplink requires precise frequency adjustment and there’s a delay on the downlink, but the signal is strong”. A recording of the transponder can be heard at

The launch from the Taiyuan Space Launch Center was planned for December 26 but postponed due to adverse weather. It had been planned it would go into a 530 km circular Sun-Synchronous Orbit (SSO) but instead the orbit appears to be 524 x 212 km which will give an orbital lifetime of just one or two months.

BY70-1 is a 2U CubeSat project for school education and amateur radio. It features 3-axis stabilization and deployable solar panels. In addition to the FM transponder BY70-1 has a camera and it is planned to download images and telemetry via a 9600 bps BPSK downlink.

The IARU amateur satellite frequency coordination pages list these frequencies:
• 145.920 MHz uplink
• 436.200 MHz downlink
A 67 Hz CTCSS (PL Tone) is required.

On the AMSAT Bulletin Board Mac AE5PH has provided a list of the channel settings he uses:

 Chan        RX          TX     TX PL Tone
BY70-1    436.2100    145.9175    67 Hz
BY70-2    436.2075    145.9175    67 Hz
BY70-3    436.2050    145.9175    67 Hz
BY70-4    436.2025    145.9200    67 Hz
BY70-5    436.2000    145.9200    67 Hz
BY70-6    436.1975    145.9200    67 Hz
BY70-7    436.1950    145.9225    67 Hz
BY70-8    436.1925    145.9225    67 Hz
BY70-9    436.1900    145.9225    67 Hz

His rig supports 2.5 kHz channel spacing, for 5 kHz step rigs just omit the intermediate channels.
Note: If your rig has selectable FM filters the wider filter should give better results.

For the SatPC32 Doppler.sqf file Henk PA3GUO suggests: BY70-1,436200,145920,FM,FM,NOR,0,0,FM

BY70-1 has been added to the satellite pass predictor at

See the article by Daniel Estévez EA4GPZ / M0HXM – GNU Radio decoder for camera images from BY70-1 satellite

BY70-1 links

Follow Mingchuan Wei BG2BHC

Keplerian Two Line Elements (TLEs) ‘Keps’ for new satellites launched in past 30 days. It is believed BY70-1 may be object 41909, 2016-083C

Adding new satellites to SatPC32, Gpredict and Nova