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SKY SURFING RADIO FROM THE OUTER REACHES Keith Baker, KB1SF / VA3KSF keithbaker@monitoringtimes.com A Flock of Other Amateur Radio Satellites Up to now, I’ve been sharing information about the mainstays of our Amateur Radio satellite fleet and how you can receive their signals or, if properly licensed, actually work through those that have transponders. In this installment, I’ll discuss a number of other amateur satellites that have launched in the last few years and then bring you up-to-date on some of the latest happenings in the amateur satellite world. ❖ An Aging Fleet In my work as the past president and current treasurer of AMSAT-North America, I’m frequently asked, “With all the on-orbit failures of AMSAT’s satellites lately, what satellites are left for me to work?” Clearly, we have recently lost our most popular so-called “EZ-sats” (AO-51) to battery failure. Some others (like SumbandillaSat (SO-67) and Hope OSCAR 68 (HO-68), which showed great promise soon after their launch, are now in beacon mode (if that) most of the time. In addition, satellites like AO-7 (which is now nearing its fortieth anniversary in orbit) is only functional while in sunlight, and VO-52’s Indian ground handlers recently had to switch the satellite to one of its backup analog transponders as the primary transponder experienced an on-orbit failure. Even the Mode V/U (Mode J) transponder aboard JAMSAT’s venerable Fuji OSCAR 29 (FO-29) had to be turned off by its handlers for many months because its orbit progressed into long periods of darkness. But, despite all these failures, the good news is that there are still several fully functioning Amateur Radio satellites available to listen to (or work through) most of the time. Satellites like AO-27 and SO-50 now carry the bulk of FM traffic and FO-29’s analog transponder has now come back to life as strong as ever. What’s more, there’s an emerging class of satellites now in orbit that are fun to listen to even if they don’t have transponders aboard. Most are in a satellite class we call “CubeSats.” ❖ The CubeSats In a previous column, I briefly described this whole new class of satellites, based on a design that now appears poised to become the future of the Amateur Satellite Service. Measuring only 4 inches on a side, these tiny satellites (sometimes also called “nanosatellites”) are now being built, launched and/or controlled in ever increasing numbers by numerous organizations (primarily educational institutions) around the world. While some of these organizations have links to amateur radio, most do not. The bulk of these satellites have digital downlinks. A few take pictures. But most are placed in orbit for the express purpose of conducting various scientific experiments. And while some of these experiments are of interest to amateur radio operators, most are not. Unfortunately, when their original scientific experiments are complete, many of them die on orbit or revert to beacon mode…if they even last that long. However, despite their shortcomings, CubeSats are the future of this part of the hobby. They are reasonably inexpensive to build and still quite affordable (less than $100K) to launch. However, they are not without their own built-in problems. For example, because these satellites are so small, they tend to run “cold” on orbit, as they cannot absorb enough heat when in daylight to keep their internal parts warm enough during eclipse to function properly. Batteries, in particular, usually will not accept a full charge if their internal temperature falls below freezing. This issue is further complicated by the fact that the cross sectional area of these satellites does not allow for large enough solar panels to generate enough extra onboard power that could be used for internal heating. As a result, these satellites often run in a negative power mode that eventually “does them in,” sometimes soon after launch. But, as I’ve also said, even though most of these satellites do not contain transponders, they are still fun to listen for. So, let’s shine the spotlight on a few of these CubeSats that were still operational at press time (late June 2012). Unfortunately, some (or all) of these satellites could very well be partially or completely defunct by the time you read this, so “your mileage may vary.” ❖ PW-Sat PW-Sat is the first Polish satellite. Its construction was an initiative of the students of Warsaw University of Technology (in Polish - The Politechnika Warszawska, therefore the “PW” in the satellite’s name) working within the Students’ Space Association and Student Space Engineering Scientific Group. PW-Sat was successfully launched from Koruou, French Guyana on February 13, 2012. The satellite is a 1U Cubesat (approximately The flight model of PW-Sat. (Courtesy: Warsaw University of Technology) 4 inches square) and its stated mission is to (eventually) test de-orbiting techniques at the end of its on-orbit life. At press time its Mode U/V (Mode J) transponder was still operational. More information (in Polish) about the project can be found at: www.pw-sat.pl. ❖ DO-64 (Delfi-C3) Delfi-C3 is the first nanosatellite built as a student project at the Delft University of Technology in the Netherlands. The satellite is based on the CubeSat concept in a “3U” design….that is, three single (so-called “1U”) CubeSat frames stacked on top of one another. An artist’s concept of how the Delfi-C3 satellite might appear in orbit. (Courtesy: Delft University) 66 MONITORING TIMES August 2012
A number of novel technologies are being tested on board the satellite including a thin film solar cell experiment and an autonomous wireless sun sensor experiment. Delfi-C-3 was successfully launched on April 28th, 2008 at 03:54 UTC on a PSLV launch vehicle from the Satish Dhawan Space Center in India. As of this writing, Delfi-3C was still operational with a telemetry (science) beacon downlink centered on 145.870 MHz. However, its linear uplink and downlink analog transponders, although activated soon after launch, were not operational. The latest status of the satellite can be found on the Delfi-C3 Web site at: www.delfic3.nl. ❖ FO-69 and FO-70 (Fastrac-1 and 2) Fastrac-1 and 2 are a pair of student-built nanosatellites from the University of Texas at Austin (USA) built to investigate relative navigation, attitude determination with GPS, and a micro-discharge plasma thruster. After their primary science missions are completed (and assuming they survive that long!) one or both satellites may be opened for general amateur Radio use as digipeaters using 1200 and 9600 Baud packet radio. Fastrac 1 and 2 undergoing final electronic testing prior to launch (Courtesy: University of Texas at Austin) Fastrac-1 and 2 were successfully launched by a Minotaur launch vehicle from the Kodiak Launch Complex in Alaska on November 20, 2010 into a 650 km circular orbit. At press time, the digital transponders aboard FO-69 and FO- 70 were not operating, but their 2m and 70cm beacons were being transmitted. ❖ (AO-70) (AubieSat-1) AubieSat-1 (AS-1) is an undergraduatebuilt CubeSat satellite developed by Auburn University in Alabama (USA). It was successfully launched into a somewhat elliptical 816 X 458 km Orbit from Vandenberg AFB, California on October 28, 2011. AubieSat-1 transmits with a power of about 800 milliwatts on a downlink frequency of 437.475 MHz. The beacon signal, along with telemetry, is sent using continuous wave (CW) Morse code at about 20 words per minute. More information on the status of AO-70 can be found at: www.space.auburn.edu. These are just a few of the current “flock” of small satellites that are now in orbit and available for you to hear (or, if properly licensed, to actually talk through). However, there are many more satellites that have been recently launched than I have room to list here. An excellent chronological outline of all of our amateur satellites (listed by launch date along with their current operational status) can always be found on the AMSAT Web site at: www.amsat.org/amsat-new/satellites/ history.php. SELECTED FREQUENCY AND MODE DATA SATELLITE Uplink (MHz) Downlink (MHz) Mode PW-Sat 435.020 145.900 FM / DSB DO-64 (Delfi-C3) 145.870 CW Telemetry Beacon Fastrac-1 145.980 437.435 (FO-69) 145.825 9600 and 1200 Baud AX.25 Packet Fastrac-2 (FO-70) AubieSat-1 (AO-71) 435.025 437.435 145. 825 437.475 Fastrak 1 and 2 were successfully launched by a Minotaur launch vehicle from the Kodiak Launch Complex in Alaska on November 20, 2010. They became FO-69 and FO-70 when they were activated on orbit. (Courtesy: University of Texas at Austin) 9600 and 1200 Baud AX.25 Packet 1200 Baud AX.25 CW Beacon (20 WPM) The flight model of AubieSat (AO-71). (Courtesy: Auburn University) ❖ Project FOX Update In my February MT column, I introduced you to AMSAT-North America’s next big project…a Cubesat design we call “FOX.” Then, in my May column, I reported that the first satellite in this series (FOX-1) had recently been selected by NASA for one of their reduced cost ElaNa launches (Educational Launch of Nanosatellites program) in the 2013-2014 time frame. Since that announcement, FOX experimenters completed an extensive Preliminary Design Review (PDR) of the entire project. During the PDR, all mechanical, RF, control, power, and related designs and issues were extensively discussed. The current status of the project was also evaluated, and the need for further development for various systems and subsystems was refined. AMSAT’s Vice President for Engineering Tony Monteiro, AA2TX, characterized the review as, “Very productive.” AMSAT is now working with NASA on a detailed collaborative agreement for the launch of the satellite. It is also important to note that FOX-1 was selected to participate in the NASA ELaNa effort based on its merit in support of NASA’s strategic and educational goals. Clearly, this recognition places AMSAT in a very good position to garner future launches for its satellites under the ElaNA program. AMSAT’s Fox-1 project timeline is based on an anticipated launch for the satellite in the second half of 2013. However, NASA will determine on which specific flight each of the Project ELaNa CubeSats is carried to orbit. So, the launch timeline for FOX-1 could very well slip…or be accelerated… depending on NASA’s other launch needs. In the interim, the latest on FOX-1’s status can be found on the FOX-1 Web page at: www.amsat.org/amsatnew/fox/. ❖ Looking Ahead That’s all for this time. Clearly, it’s a very exciting time for amateur radio in space. In future columns, I’ll bring you up-to-date on the progress of the FOX-1 effort as well as the status of some of our other amateur satellites still in orbit. I’ll also highlight some exciting amateur satellite projects that are now on AMSAT’s drawing boards. See you then! August 2012 MONITORING TIMES 67
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