SB NEWS @ AMSAT $SPC0619 * SpaceNews 19-Jun-00 * BID: $SPC0619 ========= SpaceNews ========= MONDAY JUNE 19, 2000 * AMSAT PRESIDENT ON SPECTRUM * =============================== AMSAT-NA President Keith Baker reports that he has been asked to be a featured guest on the shortwave radio program "Spectrum" hosted by Mark Emanuel, N2CBO and Stan Olochwoszcz, N2AYJ. The program is scheduled to air live on shortwave radio station WWCR in Nashville, Tennessee on 5.070 MHz AM at 03:00 UTC on Sunday 18-Jun-2000. Keith indicated that he and the show's hosts will be talking about AMSAT, its origins, triumphs, and challenges. [Info via the AMSAT-NA News Service] * SUNSAT NEWS * =============== Johann Lochner reports that the SUNSAT spacecraft has recently entered a solar orbit (permanent sunlight with no eclipses). This will lead to higher spacecraft temperatures and more demanding control requirements. SUNSAT will remain sunlit until November 2000. Experiments to ensure that it survives this testing period will continue for an undetermined time. An announcement will be made when the amateur radio services are resumed. See: http://sunsat.ee.sun.ac.za/index.html for the latest information. [Info via Johann Lochner, ZR1CBC] * FM SATELLITE STATUS * ======================= Here is a one line summary of currently active FM birds that you can receive on your Mobile FM rig and mobile vertical whip antenna. New items: 1) SUNSAT has turned off APRS mode while they manage high sun temps 2) MIR again goes silent as crew heads home SAT DOWNLNK UPLINK S MODE COMMENTS ---- ------- ------- - ------------------ ---------------------------- MIR 145.985 145.985 9 S FM crew voice Off UO11 145.825 4 R FM Bell202 ASCII Telemetry only UO14 435.070 145.975 5 J FM Voice rptr lots of fun every pass AO27 436.795 145.850 3 J FM Voice rptr days only but fun SO35 145.825 436.290 8 B FM Voice rptr Off while in hot sun SO35 145.825 436.290 8 B 9600 bd FSK digi Off while in hot sun UO22 435.120 145.900 3 J 9600 bd FSK BBS ON KO23 435.170 145.900 4 J 9600 bd FSK BBS ON but with probs in eclipse KO25 436.500 145.980 3 J 9600 bd FSK BBS ON TO31 436.925 145.925 5 J 9600 bd FSK DATA ON downlinks images * If you don't hear it, then DONT TRANSMIT! Either the bird is dead or your station is deaf. Don't embarass yourself and QRM everyone! Between the hours of about 6 AM to noon and 6 PM to midnight local SUN time there is usually one of these birds in view for a few minutes to keep you entertained while traveling. UHF requires +/- 5 or 10 KHz Doppler tuning. The "S" column is a subjective signal strength assessment. A 20" vertical whip in the center of your car roof will give you success as shown below. This acts as a 3/4 wave on UHF giving almost 8 dBi above 30 degrees over a good groundplane for the UHF downlink birds. For SUNSAT which operates mode B with a stronger 2m downlink and your 50 watt mobile uplink, your normal dual-band mobile antenna will do better closer to the horizon. SIG RECEIVE RANGE USING THE 20" WHIP FOR MODE J PACSATS: --- ------------------ As a rough approximation consider this table 9 Horizon to Horizon which has been subjectively determined after 8 5 deg and above 3 months of daily monitoring. Home stations 7 10 deg and above with 50' of RG 8 should subtract about 3 from 6 15 deg and above the signals and 5/8 or dual band, or "gain" 5 20 deg and above antennas should also subtract about 2. 4 25 deg and above 3 30 deg and above The PACSATs do not officially digipeat UI 2 3 ele beam required packets, but you can still see status and 1 6 ele beam required telemetry and the USER lists on your Kenwood data radios or any radio with 9600 baud TNC. For more info on mobile satellite operations see http://web.usna.navy.mil/~bruninga/astars.html [Info via Bob Bruninga, WB4APR] * OSCAR-11 NEWS * ================= During the period 16-May to 16-June-2000, fairly good signals have been received from OSCAR-11's 145.826 MHz VHF-FM beacon. The battery voltage during daylight passes has continued to decrease. The average value observed was 13.4, with a range of 13.2 to 13.5 volts. The internal temperatures have again decreased, by about one degree C. They are now -0.5C and -2.0C for battery and telemetry electronics respectively. Further reductions in temperature are expected until July. Ground control reset the magnetorquer attitude control counters at the start of June. During May the Z-axis counter remained at its maximum value of 1024, which was reached towards the end of April. This stopped further magnetorquer firings, the attitude being controlled solely by the passive gravity gradient boom, without any spin corrections. During May, the spin period increased steadily from 286 to 450 seconds. After the counters were reset the spin period quickly settled to an nominal -350 seconds. It is interesting to note that the negative spin correction counter is now incrementing at about half the rate of the Z-axis counter. The was the nominal rate before October 1998, when the rate suddenly dropped to almost zero. The cause of this anomaly remains a mystery. Ground control has also corrected the software generated dates, but the date in the hardware generated ASCII telemetry frames is still advanced by three days. Unfortunately, the date in the hardware was set up at the start of the mission and cannot be reset. The single WOD survey of channels 10, 20, 30, 40 (+Y, -X, +X solar array currents, array voltage), dated January 06 has been transmitted. Note the year of this WOD survey is incorrectly displayed as 99. This survey clearly shows the solar eclipses, and a spin period of 340 seconds. The operating schedule remains unchanged: ASCII status (210 seconds) ASCII bulletin (60 seconds) BINARY SEU (30 seconds) ASCII TLM (90 seconds) ASCII WOD (120 seconds) ASCII bulletin (60 seconds) BINARY ENG (30 seconds) The ASCII bulletin is currently a static message, detailing modes and frequencies of all the amateur radio satellites. There are additional status blocks after each bulletin is transmitted, and between ASCII telemetry and Whole Orbit Data (WOD). The Mode-S beacon is ON, transmitting an unmodulated carrier, but telemetry indicates that it has partially failed, and delivering half power. This beacon is a useful test source for those testing Mode-S converters, prior to the launch of P3-D. However, the signals are very weak, and there is a lot of Doppler shift. Users should also note that the polarization of OSCAR-11 is left-hand circular. Even if you can't hear OSCAR-11, your equipment may still be okay for P3-D. Any reports of reception on 2401 MHz would be most welcome. Please direct them to Clive Wallis via e-mail at: g3cwv@amsat.org. The 435.025 MHz UHF beacon is normally OFF. However, it can sometimes be heard when the satellite is being commanded by ground control, ie. within range of Guildford, UK. When the UHF beacon is transmitting, the VHF beacon is normally OFF. The data transmitted is mainly binary. Listeners to OSCAR-11 may be interested in visiting a web site dedicated to the satellite. The web site contains details of hardware required and some software for capturing data, and decoding ASCII telemetry and WOD. There is an archive of raw data (mainly WOD) for analysis, which is continually being expanded as new data is captured. Also included are some audio files, examples of each type of data transmitted by OSCAR-11. Each one plays for about ten seconds. There are also examples of mode-S reception. All the audio files are zipped, so that they can be played off-line. These should help listeners identify the various types of data, and give an indication of the signal quality required for successful decoding. The URL is: http://www.users.zetnet.co.uk/clivew/ [Info via Clive Wallis, G3CWV] * NEW VERSIONS OF PREDICT RELEASED * ==================================== New versions of PREDICT, the free, open-source satellite tracking and orbital prediction software for DOS and Linux systems, have been released. This release cures some minor bugs in the way the program calculates NASA Two-Line element set checksums. Some other small code updates were also included in this release. The latest versions of PREDICT may be downloaded from: (Linux) ftp://ftp.amsat.org/amsat/software/Linux/predict-2.1.2.tar.gz (DOS) ftp://ftp.amsat.org/amsat/software/PC/tracking/predict2.zip General program information is available at: http://www.linuxfan.com/~predict/ * THANKS! * =========== Thanks to all who sent news items and/or messages of appreciation to SpaceNews in recent weeks, especially: K3GNZ * 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