SB NEWS @ AMSAT $SPC0214 * SpaceNews 14-Feb-00 * BID: $SPC0214 ========= SpaceNews ========= MONDAY FEBRUARY 14, 2000 * ASUSAT-1 LOST * ================= Assi Friedman, KK7KX / 4X1KX, reports "unfortunately, it appears that the ASUSat-1 satellite has stopped transmitting". Received telemetry has indicated the batteries aboard the satellite did not receive any charge from the solar-array. Because of this, the satellite worked for about 15 hours on battery power alone. KK7KX reports the ASUSat-1 team has no indications at this time to pinpoint the exact cause. The team is looking at the relationship between the solar-array and the power-board. According to Assi, "the ASUSat1 team is disappointed but yet very happy. The satellite provided interesting telemetry when it was alive, and we are analyzing the data at present. We were thrilled that the system powered up and did what it was supposed to. In any case, the team is looking forward to future missions!" ASUSat-1 contained an amateur packet hardware system and a 2-meter/70-cm FM voice repeater. The Air Force Minotaur had rocket successfully lifted off from Vandenberg Air Force Base with a number of satellites onboard, including the Joint Air Force-Weber State University Satellite (JAWSAT), Stanford University's Orbiting Picosat Automatic Launcher (OPAL), the Air Force Research Lab's Optical Calibration Sphere, along with ASUSat-1. The primary payload was the US Air Force Academy's FalconSat. [Info via the AMSAT-NA News Service] * STENSAT NEWS * ================ For anyone interested in tracking StenSat, controllers would appreciate full details of all contacts, including AOS and LOS times, signal strength, and tracking angles. Controllers have received a half dozen reports so far that seem to indicate that: * StenSat is leading in front of OPAL by about 1 minute. * StenSat is in transponder mode (No CW or AX.25 has been reported). Controllers suspect that StenSat is rapidly moving away from OPAL. While it remains on the same orbital track, it either leads or trails OPAL by some as yet to be determined amount. Based on the rapid deceleration of the Aerospace (tethered) picos, controllers suspect StenSat is leading OPAL. If its deceleration is on the same order as the Aerospace picos (circa one minute ahead per day after ejection), StenSat might be found around one to two minutes ahead of OPAL, but this is just a guess. Hank Heidt, N4AFL ias created a StenSat Signal Report web page that may be found at the following URL: http://www.erols.com/hheidt/signal.htm [Info via Hank Heidt, N4AFL] * ISS NEWS * ============ Launch of the International Space Station's next component, the Zvezda service module, is scheduled to occur between July 8 and 14 from the Baikonur Cosmodrome in Kazakhstan, according to NASA and the Russian Aviation and Space Agency. The Zvezda launch window will be proposed for approval to the International Space Station Partners in accordance with the ISS Control Board process within the next several weeks. Following joint meetings in Moscow, including a General Designer's Review and a Joint Program Review, Rosaviakosmos has proposed that Zvezda (Russian for "Star"), the early living quarters for crews aboard the station, be launched on a Proton rocket with second and third stage engines modified to increase reliability. The 42,000 pound Zvezda not only provides the early living quarters for astronauts and cosmonauts, but also the life support system, electrical power distribution, data processing system, flight control system, and propulsion. While many of these systems will be supplemented or replaced by later U.S. station components, Zvezda always will remain the structural and functional center of the Russian segment of the International Space Station. Zvezda has a solar-array wingspan of 97.5 feet tip to tip, and is 43 feet long from end to end. The module contains three pressurized compartments and four docking ports. Following Zvezda's launch and about 15 days of free flight, the ISS will rendezvous and dock with its newest module. Launch of Zvezda sets the stage for the launch of other ISS components undergoing final testing at NASA's Kennedy Space Center in Florida. These components include a small truss segment that will serve as the support structure for other station hardware; the first set of solar arrays; the United States Destiny laboratory; the Canadian-built space station robot arm; and several truss segments that will serve as the station's backbone for external hardware, experiments and solar arrays. Other key station components are also under development and testing in Europe and Japan. [Info via NASA by way of Roy Neal, K6DUE] * AMSAT-BB ARCHIVES * ===================== Not being too happy with the AMSAT-BB archives on the AMSAT server, Jeff Davis, N9AVG started archiving the AMSAT discussion messages in HTML format on his own machine. The result is an indexed archive that can be sorted by month, date, author, subject and thread. Jeff added the HT-Dig search engine for complete word/phrase searches. The Web-based archive may be found at: http://n9avg.org/amsat/ [Info via Jeff Davis, N9AVG] * SUNSAT NEWS * =============== SUNSAT is equipped with a high resolution imager capable of filling the 64 MB ramtray in a matter of seconds. However, because of the failed 40 Mbit/s S-band downlink, controllers are forced to download data at only 9.6 kbit/s. With about 40 minutes of useful download time per day, this is getting extremely boring (not to mention the frustration for not being able to capture such wonderful images more often). Controllers are investigating ways to better utilize the NBFM data channels available on VHF and UHF. The satellite's 40 MHz Motorola DSP56L002 platform has been commissioned at the end of last year. The SNR on the 8W downlink is extremely favorable (it still has to be measured for capacity calculations). The effective data rate could be increased by pre-processing of the image data and/or by implementing more complex modulator-demodulator pairs. A simple compression routine running on the DSP already results in an effective rate of 15k36 bit/s. Because of the high SNR the 9k6 modems can also be overclocked with limited success (up to a 30% increase in the data rate before ISI becomes a limiting factor). This option could be pushed a little further by increasing the IF bandwidth of the receivers. Any pointers to existing DSP56000 code for compression algorithms (like JPEG, wavelet and the like!) and/or modems implementing complex constellations would be most welcome. Also, ideas on the suitability of ITU recommendations for telephony modems (such as V.34) would be appreciated. Controllers would like to know if these protocols be used for simplex transmissions, or if there may be other ways to increase the data rate. Information should be directed to Johann Lochner, ZR1CBC, via e-mail at: lochner@ing.sun.ac.za * FEEDBACK/INPUT WELCOMED * =========================== Comments and input for SpaceNews should be directed to the editor (John, KD2BD) via any of the paths listed below: WWW: http://www.njin.net/~magliaco/ MAIL: John A. Magliacane, KD2BD Department of Engineering and Technology Brookdale Community College 765 Newman Springs Road Lincroft, New Jersey 07738 U.S.A. PACKET: KD2BD @ N2TDU.NJ.USA.NA INTERNET: kd2bd@amsat.org, magliaco@email.njin.net SATELLITE: AMSAT-OSCAR-16, KITSAT-OSCAR-25 <<=- SpaceNews: The first amateur newsletter read in space! -=>> <<=- Serving the planet (and beyond) since 1987 -=>> /EX