China’s twin-launch Chang’e 4 mission to the far side of the moon will place a pair of microsatellites in lunar orbit this spring “to test low-frequency radio astronomy and space-based interferometry.” The two satellites, unofficially called DSLWP-A1and DSLWP-A2 (DSLWP = Discovering the Sky at Longest Wavelengths Pathfinder), could launch this spring. The pair represent the first phase of the Chang’e 4 mission, which 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.
The two spacecraft also will carry Amateur Radio and educational payloads, but not a transponder. Developed by students at the Harbin Institute of Technology, the Amateur Radio payload on DSLWP-A1 will provide a telecommand uplink and a telemetry and digital image downlink. Radio amateurs will be able to transmit commands that allow them to send commands to take and download an image.
The satellites will piggyback on the Chang’e 4 relay package and will deploy themselves into a 200 × 9,000 kilometer lunar orbits. The 50 × 50 × 40 centimeter spacecrafts each weigh about 45 kilograms and are three-axis stabilized. Two linear polarization antennas are mounted along and normal to the flight direction. The satellites will use the moon to shield them from radio emissions from Earth.
The Harbin Institute of Technology team has proposed downlinks for A1 on 435.425 MHz and 436.425 MHz. Downlinks for A2 would be 435.400 MHz and 436.400 MHz using 10K0F1DCN or 10K0F1DEN (10-kHz wide FM single-channel data) 250 bps GMSK with concatenated codes or JT65B.
Equipped with low-frequency antennas and receivers, the astronomy objectives of DSLWP-A1 and -A2 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.
The launch is anticipated for May or June on a CZ-4C vehicle, putting the satellites’ deployment about 6 months ahead of the launch of the Chang’e 4 lander and rover.
Source:ARRL
Antenna
Radio interference from Solar Panels – RFI
The radio amateurs have known for a long time that PV installations (solar panels) could interfere. For more than 10 years, the VERON has been warning... Read more
40 Meters 4-element Wire Yagi by VE3VN
Read great article from VE3VN – 40 Meters 4-element Wire Yagi : Read more
2 Meter VHF Quarter Wave Ground Plane Antenna – Ham Radio Q&A
“Are you looking for a fun and easy antenna project? The 1/4 ground plane might be just the ticket. This particular ground plane is constructed... Read more
Q52 Relay-switched 20-17-15-12-10 meter Yagi
See Q52 20 17 15 12 10 5-band Remote Switched 2el Yagi Coverage band in 2 segments whole band whole band whole band >1.1MH... Read more
The Legendary G5RV Antenna – ARRL The Doctor is In podcast
“The Legendary G5RV Antenna” is the topic of the new (August 15) episode of the ARRL The Doctor is In podcast. Listen…and learn! Read more
BIG SIGNAL DX-Quad – 5 Bands!
Discover the BIG SIGNAL DX-Quad antenna , this new design of a single element Multi-Band Quad covers up to 5 bands in HF from 10 to 20 meters. An incr... Read more
VHF
How to work amateur radio satellites with your handheld (HT) radio
How to work amateur radio satellites with your handheld (HT) radio Visit the Worldwide Radio Forum at worldwidedx.com Read more
New! Yaesu FTM-3200DR – 2M 65W FM/C4FM Mobile
Yaesu FTM-3200DR FTM-3200DR 144MHz 65W C4FM/FM Single Band Digital Mobile Transceiver Rugged & Compact 2m Digital Mobile with Front Speaker Radio... Read more
Toptek Communications PA-85V VHF Power Amplifiers
Amplifier, VHF, 85 W, 138-174 MHz, Each Brand:Toptek Communications Manufacturer’s Part Number:PA-85V Part Type:VHF/UHF Amplifiers Product Line:... Read more
VHF and UHF FM Transceiver MT-777
Application For on-site communications such as warehouse, manufacturing, hospitality, school and security occasion, etc. Main Features ■ 50 CTCS... Read more
Icom IC-M73PLUS
Icom IC-M73PLUS PROFESSIONAL VHF MARINE TRANSCIEVER The IC-M73PLUS builds on many of the features that made the IC-M71 the choice of many marit... Read more
Icom Launch New IC-A220T 8.33kHz Air Band Panel Mount VHF Radio
The IC-A220T, Icom’s next generation 8.33kHz* air band panel mount transceiver, is now TSO / ETSO approved** and available for sale. The long awaited... Read more
News
Quantum Receiver Can Detect Huge Swath of the RF Spectrum
US Army researchers have built a so-called “quantum sensor,” which can analyze the full RF spectrum and real-world signals, a report on Physics.org sa... Read more
Approaches to Tackle Noise Problems Vary, Remedies Elusive
RF noise is a frequent discussion topic among radio amateurs. A proliferation of electronics has cluttered and complicated the noise environment; it’s... Read more
ARISS, NASA, and ESA Continue to Probe Amateur Radio Problems on ISS
Amateur Radio on the International Space Station (ARISS) International Chair Frank Bauer, KA3HDO, reports that the ARISS team has been working closely... Read more
Yaesu FT-DX10 HF Transceiver – Is it Right for You?
We take a look at one of the most recent HF transceivers to come onto the ham radio market. Could this be the new FT-101E that was one of the best sel... Read more
What is the Base Holding Up My Hexbeam?
William Noble asks about the base used to hold up my MFJ-1846 Hex Beam antenna. The actual base that allows for a fold-over mast was designed by frien... Read more
ARISS APRS Testing
ARISS APRS TestingThe ARISS team has been working very closely with NASA and ESA to identify potential ARISS radio anomaly causes and resolve the radi... Read more
Review
Warrantless Search Of Ham Radio Operators? No Fourth Amendment Rights?
Responding to comments and recent videos here on Youtube. Is there a big threat to amatuer radio operators fourth amendment rights? Are we opening out... Read more
Baofeng UV-9R TP 18-watt Power Testing | UV9R Plus HT
Baofeng UV-9R TP 18-watt HT Ham Radio Unboxing and power testing – let’s see if this 18-watt HT does what it is advertised to do! Read more
ACOM – Manufacturers Showcase
ACOM team to discuss the latest amplifier technology. Tune in and ask the team questions. Read more
Ham Radio vs CB
Ham Radio vs CB, Citizen’s Band Radio – Ham Radio compared to CB frequencies and modes – which ones is better? Today let’s tal... Read more
Ham Radio Forms a Planet-Sized Space Weather Sensor Network
The article “Ham Radio Forms a Planet-Sized Space Weather Sensor Network,” appeared on February 9 in Eos, Earth & Space Science News — an American... Read more
SCU-LAN10 with FTdx101 / FTdx10 Overview
SCU-LAN10 with FTdx101 / FTdx10 Overview Read more