CAMSAT, the Chinese Amateur Satellite Group, has submitted requests to the IARU for frequency coordination for three new amateur satellites.
CAS-5A is a 6U CubeSat with several amateur transponders: A 30 kHz wide 15 meter to 10 meter linear transponder, a 15 kHz wide 15 meter to 70 cm linear transponder, a 30 kHz wide 2 meter to 70 cm linear transponder, and a 2 meter to 70 cm FM repeater. The satellite also has 10 meter and 70 cm CW beacons as well as a 70 cm 4.8k / 9.6k GMSK telemetry downlink.
CAS-5B is a 90 mm L x 80 mm W x 50 mm H 0.5 kg femtosatellite with a 70 cm CW beacon.
CAS-5A and CAS-5B are scheduled to launch in September from Jiuguan Launch Center into a 539 km x 533 km 97.5 degree inclination orbit.
CAS-6 is an amateur payload aboard a 50 kg microsatellite with a 20 kHz wide 70 cm to 2 m linear transponder, a VHF CW beacon, and a 4.8k GMSK telemetry downlink. Launch is planned from a Sea Launch Pad from the China Academy of Launch Vehicle Technology in September into a 579 km x 579 km 45 degree inclination orbit.
On the 03:25 UTC pass on January 26, 2018, AMSAT Vice President – Engineering Jerry Buxton, N0JY, announced that AO-92 had been commissioned and formally turned the satellite over to AMSAT Operations. AMSAT Vice President – Operations Drew Glasbrenner, KO4MA, then declared that AO-92 was now open for amateur use. Audio of the handover and first operational pass can be heard here:
Initially, the U/v FM transponder will be open continuously for a period of one week. After the first week, operations will be scheduled among the U/v FM transponder, L-Band Downshifter, Virginia Tech Camera, and the University of Iowa’s High Energy Radiation CubeSat Instrument (HERCI).
AO-92 was launched on the PSLV-C40 mission from Satish Dhawan Space Centre in Sriharikota, India on January 12, 2018. For the past two weeks, the AMSAT Engineering and Operations teams have been testing the various modes and experiments on board. Testing has shown that both the U/v FM transponder and L-Band Downshifter work very well. The Virginia Tech camera has returned stunning photos and data from HERCI has been successfully downlinked.
AMSAT thanks the 178 stations worldwide that have used FoxTelem to collect telemetry and experiment data from AO-92 during the commissioning process. The collection of this data is crucial to the missions of AMSAT’s Fox-1 satellites. Please continue to collect data from AO-85, AO-91, and AO-92.
The AMSAT Engineering and Operations teams have been hard at work testing the various modes and experiments aboard AO-92 since its launch on January 12th. Since the last update, testing has concentrated on the University of Iowa’s High Energy CubeSat Radiation Instrument (HERCI) experiment and the AMSAT L-Band Downshifter.
The HERCI experiment was activated for the first time on January 18, 2018. According to Don Kirchner, KDØL, Research Engineer at the University of Iowa, “HERCI is intended to provide a mapping of radiation in a low earth orbit. This is of scientific interest for planning CubeSat test flights for low energy X-Ray detectors.”
“The instrument consists of a digital processing unit (DPU) derived from processors currently in orbit around Saturn on Cassini and on the way to Jupiter on the Juno spacecraft,” said Kirchner during a 2015 interview. “The DPU was shrunk to a CubeSat form factor with funding from the Iowa Space Grant Consortium.”
While the HERCI experiment collects data continuously while the transponder is in operation, the data is only downlinked in the satellite’s high-speed data.
After testing operation of the HERCI experiment and the downlinking of the experiment data, focus turned to the AMSAT L-Band Downshifter. When enabled, the L-Band Downshifter converts signals received on 1267.350 MHz and injects them into the satellite’s 435 MHz receiver. Due to the increased path loss on 1267 MHz and the utilization of the satellite’s 435 MHz receive antenna on 1267 MHz, pre-launch estimates suggested that around 100 watts ERP may be required for horizon to horizon access in this mode. As always, pre-launch estimates are subject to change after real-world testing in-orbit.
At 02:19 UTC on January 20, 2018, the L-Band Downshifter was commanded on for the first time. Initial testing showed promising results. Your author was able to access the transponder with an Alinco DJ-G7T HT with 1 watt output into a Comet CYA-1216E yagi. Telemetry analysis showed that the Downshifter was functioning normally and AMSAT announced open testing.
Reports flowed in of QSOs occurring over Europe and Japan. Many reported QSOs made with 10 watts or less to modest yagi antennas. EB1AO reported success using 2-3 watts output to a small yagi. IW1DTU reported using 10 watts to a horizontally polarized 10 element loop yagi. IU2EFA reported two QSOs made using 10 watts to a vertical groundplane antenna. Reports from Japan were similar. JK2XXK reported two QSOs with 10 watts to a vertically polarized 17 element loop yagi and JA6PL reported a QSO with 10 watts to a horizontally polarized 23 element yagi.
The first open pass over North America occurred at around 02:00 UTC on January 21, 2018. Seven stations were heard, your author, KE4AL, WB8OTH, WB8RJY, NS3L, N8TLV, and VE4AMU. KE4AL and VE4AMU were using similar stations, KE4AL was using a Kenwood TM-942A (10 watts output) and a Comet CYA-1216E yagi modified with holes drilled in the boom to add 2 meter Arrow II elements. VE4AMU was using the same antenna with a Kenwood TM-941A mobile radio. Your author was also using that antenna, but with an Alinco DJ-G7T handheld and was able to open the transponder at around 10 degrees of elevation. Most impressively, N8TLV was heard using just a Yaesu FT-104 handheld transceiver and the stock rubber duck for the uplink. He was weak, but readable from around 35-38 degrees of elevation. AMSAT plans to publish articles in the future discussing equipment options for use on the L-Band uplink.
Audio from your author’s recording of the AO-92 Mode L/v pass over North America can be heard here:
The L-Band Downshifter operates on a 24 hour timer and shut off on schedule around 02:19 UTC on January 21, 2018. Tests of the various modes and experiments continue. AO-92 is on track to be commissioned and handed over to AMSAT Operations on Friday, January 26th.
The first thirty-six hours of AO-92’s life in orbit have seen a flurry of activity as the AMSAT Engineering and Operations teams walk through an extensive checklist of tests required to check the functionality of the satellite’s on-board systems.
The first crucial test came on the initial pass over AMSAT command stations hours after launch. Around 15:00 UTC on January 12, 2018, AMSAT command stations successfully issued the first command to the satellite, changing it from the initial Beacon Mode to Safe Mode. The switch to Safe Mode allowed the collection of min and max data for the various telemetry values.
As AMSAT Engineering continued to evaluate the data received, the decision was made to test the U/v FM transponder briefly on the evening passes over North America. At approximately 01:30 UTC on January 13, 2018, the satellite was commanded to Transponder Mode for the first time. Initial tests show the transponder functions very well. One testing station was able to access the satellite using 5 watts from an HT to a whip antenna from inside his house at approximately ten degrees of elevation. AMSAT Engineering reminds all amateur radio operators that, although the satellite may be found in Transponder Mode at times during the commissioning process, it is essential to not transmit to the satellite before it is opened for general use as you may interfere with various tests that need to be performed.
With the transponder successfully tested and telemetry values continuing to be nominal, attention turned to the Virginia Tech camera. At about 14:30 UTC, the camera was turned on and quickly returned it’s first image of Earth. On the next pass over North America, the camera was again turned on and several images flowed into AMSAT servers. Images captured and uploaded can be found at https://www.amsat.org/tlm/fox1d/images/
AMSAT plans further testing of the Virginia Tech camera during the early hours of January 14, 2018 (UTC). If not shut off by a command station, the camera remains active for a period of 40 minutes following activation, so the active period may vary depending on when the camera is activated.
January 14, 2018 Camera On Times (Approximate)
01:12 UTC – 01:52 UTC
02:42 UTC – 02:51 UTC
This should provide an opportunity for stations in areas including Russia, China, and Japan to receive pictures from the Virginia Tech camera. Please be sure that FoxTelem’s source is set to “Auto” so you will be able to receive either high-speed frames carrying camera payloads or data under voice (DUV) frames when the satellite is in Safe Mode or Transponder Mode. If using an external audio source for FoxTelem, be sure you are set for a minimum bandwidth of 20 kHz to receive the high-speed data.
Thank you to all stations who have uploaded telemetry data to AMSAT servers. As of 18:00 UTC on January 13, 2018, a total of 90 unique stations have contributed telemetry from AO-92. Continued collection of telemetry data is essential to the commissioning process. AMSAT greatly appreciates the participation of the amateur radio community in collecting telemetry for the Fox-1 satellites.