What is the CO-66 downlink frequency?

CO-66 transmits on 437.485 MHz (CW 18 bd), 437.485 MHz (FMN), 437.485 MHz (AFSK 1k2) and 437.485 MHz (SSTV).

When does CO-66 pass over my location?

Open CO-66 on the live map and enter your Maidenhead locator or use GPS: the tracker lists the passes of the next 24 hours with AOS, maximum elevation and LOS, and shifts the frequencies for Doppler.

CO-66 (SEEDS II): Frequencies, Status & Passes

Next passes over your station

Pass times depend on where you are. Track CO-66 on the live map to see its next passes over your station.

CO-66 frequencies

Uplink	Downlink	Beacon	Mode
—	437.485 MHz	—	CW 18 bd
—	437.485 MHz	—	FMN
—	—	437.4857 MHz	CW
—	437.485 MHz	—	AFSK 1k2
—	437.485 MHz	—	SSTV

Nominal frequencies, without Doppler. The live map shifts them for your station during a pass. Frequencies: SatNOGS DB (modified: working amateur transmitters only, in MHz), CC BY-SA 4.0.

About CO-66

CO-66 (CubeSat-OSCAR 66), launched as SEEDS II, is a 1U CubeSat of Nihon University in Japan. The first SEEDS was lost on 26 July 2006 when its Dnepr rocket failed shortly after liftoff; the rebuilt SEEDS II was launched on 28 April 2008 on an Indian PSLV rocket from Sriharikota, together with CO-65 (Cute-1.7+APD II) and Delfi-C3.

The satellite's mission was to communicate with amateur ground stations, collect housekeeping data and study its own orbit and attitude. It has a CW transmitter, an FM transmitter and an FM receiver, all in the 430 MHz amateur band, so when active its signals could be received with a simple 70 cm receiver.

After more than eighteen years in orbit, CO-66 has come down to about 455 km (CelesTrak, October 2026).

Status

Listed as working, but nobody reported hearing CO-66 on AMSAT in the last 30 days.

From reports filed on AMSAT, last 30 days.

Orbit

Type	Low Earth orbit
Altitude	453–457 km
Inclination	97.8°
Period	93.7 min
TLE epoch	2026-10-27 22:29 UTC

Orbital elements: CelesTrak, checked every 3 hours.

Questions about CO-66

What is the CO-66 downlink frequency?: CO-66 transmits on 437.485 MHz (CW 18 bd), 437.485 MHz (FMN), 437.485 MHz (AFSK 1k2) and 437.485 MHz (SSTV).
What is the CO-66 beacon frequency?: The beacon is on 437.4857 MHz.
Is CO-66 active?: Listed as working, but nobody reported hearing CO-66 on AMSAT in the last 30 days.
When does CO-66 pass over my location?: Open CO-66 on the live map and enter your Maidenhead locator or use GPS: the tracker lists the passes of the next 24 hours with AOS, maximum elevation and LOS, and shifts the frequencies for Doppler.

CO-66