China’s twin-launch Chang’e 4 mission to the far side of the moon will place a pair of microsatellites in lunar orbit “to test low-frequency radio astronomy and space-based interferometry.” The two satellites, DSLWP-A1 and DSLWP-A2 (DSLWP = Discovering the Sky at Longest Wavelengths Pathfinder) are expected to launch in June. They will carry Amateur Radio and educational payloads, but not a transponder.
Equipped with low-frequency antennas and receivers, the astronomy objectives of the two spacecraft will be to observe the sky at the lower end of the electromagnetic spectrum — 1 MHz to 30 MHz — with the aim of learning about energetic phenomena from celestial sources. They will use the moon to shield them from radio emissions from Earth.
Developed by students at Harbin Institute of Technology (BY2HIT), the Amateur Radio payload onboard DSLWP-A1 will provide a telecommand uplink and telemetry/digital image downlink. The open telecommand protocol is designed to allow amateurs to send commands to take and download images. DSLWP-A1 downlinks are 435.425 MHz and 436.425 MHz; DSLWP-A2 downlinks are 435.400 MHz and 436.400 MHz, and they will use 250/500 bps GMSK using 10K0F1DCN or 10K0F1DEN (10 kHz wide FM single-channel data) with concatenated codes or JT4G. JT4 uses four-tone FSK, with a keying rate of 4.375 baud; the JT4G sub-mode uses 315 Hz tone spacing and 1260 Hz total bandwidth.
The microsatellites represent the first phase of the Chang’e 4 mission. The satellites will piggyback on the Chang’e 4 relay package and will deploy into 200 × 9,000 kilometer lunar orbits. The mission involves placing a relay satellite in a halo orbit to facilitate communication with the Chang’e 4 lander and rover, which will be sent to the far side of the moon in December. Because the moon’s far side never faces Earth, the satellite is needed to serve as an Earth-moon relay. The Chang’e 4 mission will be the first-ever attempt at a soft-landing on the far side of the moon.
These two folding arm units are ready for connecting to the array box of your choice, and attaching to either the sturdy Quadrastand or Permanent Mounting Stand. • Lightweight aluminum • Natural Aluminum Finish or Black Powder Finish... Read more
Sweden’s AMSAT-SM has released a short video showing communications via the amateur radio satellite AO-73 (FunCube-1) using the popular digital mode FT4. This is a short video of FT-4 communication via satellite AO-73 with SDR-Con... Read more
ACOM team to discuss the latest amplifier technology. Tune in and ask the team questions. Read more
New Controller for ANANs/OpenHPSDR, compatible with all ANAN radios! **Dual Receive with independent Panadapter/waterfall **PureSignal Predistortion Supported **Diversity Receive **Supports latest Noise mitigation NR2 & Spectral Noise B... Read more
“Nestled deep in the Chequamegon-Nicolet National Forest in Northwest Wisconsin is the small town of Clam Lake. Clam Lake is best known for the... Read more
K4BEN, announces the official beta of his Remote Radio Service, DXRemote.net. It is a very simple concept: his enterprise-class, redundant n... Read more