What is the AO-123 uplink frequency?

AO-123 listens on 145.850 MHz (FM).

What is the AO-123 downlink frequency?

AO-123 transmits on 435.400 MHz (FM), 10460.000 MHz (QPSK 1000k), 435.400 MHz (BPSK 9k6) and 436.210 MHz (BPSK 9k6).

When does AO-123 pass over my location?

Open AO-123 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.

AO-123 (ASRTU-1): Frequencies, Status & Passes

Next passes over your station

Pass times depend on where you are. Track AO-123 on the live map to see its next passes over your station.

AO-123 frequencies

Uplink	Downlink	Beacon	Mode
145.850 MHz	435.400 MHz	—	FM
—	10460.000 MHz	—	QPSK 1000k
—	435.400 MHz	—	BPSK 9k6
—	436.210 MHz	—	BPSK 9k6

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 AO-123

AO-123 (ASRTU-OSCAR 123), launched as ASRTU-1, is a 12U CubeSat built by students of the Harbin Institute of Technology in China and Amur State University in Russia under the Association of Sino-Russian Technical Universities. It was launched on 4 November 2024 on a Soyuz rocket from Vostochny, and AMSAT gave it its OSCAR number later that month. The Harbin team had earlier built LilacSat-1, LilacSat-2 and the DSLWP lunar satellites.

The main amateur payload is a V/u FM repeater: transmit on 145.850 MHz with a 67.0 Hz CTCSS tone and listen on 435.400 MHz. When an uplink ends and no new signal arrives within half a second, the satellite sends a short telemetry burst, so expect a data burst after each over before the next station replies. The downlink is on 70 cm, so expect about ±10 kHz of Doppler there and retune in 5 kHz steps during the pass.

The satellite also carries cameras: low-resolution pictures come down as SSDV packets on 436.210 MHz, and high-resolution images on a 10.460 GHz downlink. The IARU coordination record also describes an open telecommand that lets radio amateurs ask the satellite to take and download pictures.

Status

Active: amateurs reported hearing AO-123 on AMSAT 7 h ago.

From reports filed on AMSAT, last 30 days.

Orbit

Type	Low Earth orbit
Altitude	445–462 km
Inclination	97.3°
Period	93.7 min
TLE epoch	2026-10-28 14:27 UTC

Orbital elements: CelesTrak, checked every 3 hours.

Questions about AO-123

What is the AO-123 uplink frequency?: AO-123 listens on 145.850 MHz (FM).
What is the AO-123 downlink frequency?: AO-123 transmits on 435.400 MHz (FM), 10460.000 MHz (QPSK 1000k), 435.400 MHz (BPSK 9k6) and 436.210 MHz (BPSK 9k6).
Is AO-123 active?: Active: amateurs reported hearing AO-123 on AMSAT 7 h ago.
When does AO-123 pass over my location?: Open AO-123 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.

AO-123