Posted: Sat Sep 3, 1988 8:33 PM GMT Msg: IGII-3721-2779 From: VRIP To: IS Subj: ANS.247 SB ALL @ AMSAT $ANS-247.01 AMSAT Weekend News Summary HR AMSAT NEWS SERVICE BULLETIN 247.01 FROM WA2LQQ WARWICK, NY September 03, 1988 TO ALL RADIO AMATEURS BT AMSAT OSCAR 13 operations continue on track. The current schedule should remain in effect until September 21. After that, a new schedule will be installed which will reflect the spacecraft attitude change which commences September 19. The reorientation should take only a few orbits to complete. This will be the first seasonally-related attitude change for AO-13. On Friday, September 9, a special Mode L test will be performed to analyze the effects of radar noise on the Mode L receiver. As previously noted, Mode L receiver AGC levels have been up to -14 dB when the antenna is earth-pointing (at apogee) even when there are no audible signals in the passband. The AGC level falls to 0 dB (no gain reduction) when the receiving antenna is off-pointing from earth and looking towards space. This is the case near perigee. On September 9, Mode L will be in operation throughout the entire orbit to allow measurements to be taken. The Mode L transponder should NOT be used. Reports from stations equipped with good 70 cm receiving systems and a spectrum analyzer are invited. They should check the entire passband to gather more information on the source of the noise according to DB2OS. Telemetry reports on Mode L AGC levels, especially from Pacific basin stations, are very much needed. Telemetry reports of the Mode L AGC and transmitter power should be forwarded to WA3WBU as previously described or may be relayed via AMSAT net stations. No further progress on RUDAK has been reported but testing continues in hopes of finding a way around the current impasse. The AMSAT-NA microsat project took a big step forward in late August when accurate models of the generic satellite passed a rigorous series of shake and vibration tests. The tests subjected the microsat bus to vibration levels much higher than AO-13 was subjected to. The tests were performed at Utah State University in Logan and, according to W3GEY, were passed with flying colors. Acceleration levels over 14 Gs in the vibration test and over 44 Gs in the shock test caused no problems for the rugged microsat bus, W3GEY said. The AMSAT satellite news nets debuted on Friday, September 2 on Modes B and L. The Space Education Net will debut on AO-13 on Saturday, September 3. W8GQW says AMSAT nets will appear on AO-13 regularly; weekly if satellite windows allow. Watch these bulletins for times and dates. Downlink frequencies will be 145.960 and 435.888 MHz for Modes B and L, respectively. Mode J users will be accommodated on a downlink of 435.988 MHz. The SEN will use frequencies of 145.960 and 435.900 MHz according to K9PVW. WA5ZIB says the first AO-13 ZRO-Test trial run will be September 24. VK5AGR says AO-13 telemetry equations will be included in the telemetry stream beginning September 5. The equations will be sent a few at a time over a period of weeks. NASA prediction bulletin 16 for AO-13 has finally got the correct ephemeris for the satellite...almost. The orbit number should be 148 instead of 149 says G3RUH. G3RUH was recently qualified as an AO-13 command station, the first from the UK. Distribution of AMSAT bulletins via packet radio on AO-13 will begin on a trial basis shortly. Initially FSK will be used. Later PSK will be added. Finally, FSK will be phased out. The operating schedule will be announced shortly. AO-13 Mode S tests are expected to commence soon. AO-10 is out of service for an indeterminate period due to poor sun angles. The AMSAT satellite frequency guides are being mailed to all donors. If you are eligible to receive one, you should have yours by September 15. First Day Club certificate requests continue to arrive. All certificates will be mailed out by September 30. AMSAT has re-instituted its traditional orbit sponsor program for support of operations by satellite users. AMSAT HQ has the details: 301-589-6062. /EX SB ALL @ AMSAT $ANS-247.02 AO-13 and FO-12 Ops Sked HR AMSAT NEWS SERVICE BULLETIN 247.02 FROM WA2LQQ WARWICK, NY September 03, 1988 TO ALL RADIO AMATEURS BT Here is the AO-13 operating schedule currently in use. This schedule will remain in effect until September 21 when a new schedule will be implemented. Deviations from this schedule may occur to facilitate important engineering tests. *** S P E C I A L T E S T S September 9. Do not use the satellite! *** Revised Operating Schedule: V3.1 19Aug88 +---------------------------------------------------------------+ | Mode | From | Thru | Remarks | Duration | | |(Inclus)| (Inclus)| | MA Minutes| |========|========|=========|==================================== | Off | MA 241 | MA 002 | Solar eclipse window | 18 48.3 | | Mode B | MA 003 | MA 099 | | 97 260.2 | | Mode L | MA 100 | MA 150 | Mode JL optional | 51 136.8 | | Mode B | MA 151 | MA 240 | | 90 241.4 | |--------+--------+---------+----------------------+------------+ | Mode S | | | Soon | | | RUDAK | | | Testing; ops pending | | +--------------------------------------------------+------------| The omni antennas are enabled from MA 224 thru 032. According to G3RUH, AO-13's attitude as of 20 August was BLON=182.8 and BLAT=-0.7. James says the rate of change of the Bahn Coordinates due to natural movements of the orbit is BLON +0.0 deg/day and BLAT -0.1 deg/day. On or about 19 September, the attitude will be changed to BLON=210 and BLAT=+5 to respond to seasonal sun angle changes says DB2OS. Here is the FO-12 operating schedule for September as provided by JARL. Mode Beginning Date Time JA 03Sep 0758 D 05 0201 JA 07 0623 D 08 0529 JA 10 0543 D 12 0150 JD* 14 0000 JD 14 0610 DI 15 0516 JD 17 0124 DI 18 0435 JD 21 0355 DI 22 0301 JD 24 0314 DI 25 0220 JA 27 0234 D 28 0140 *On September 14 from 0000 to 0204, telemetry acquisition will be done every 2 seconds and the mailbox function will be disabled. A QSL card will be sent to those submitting telemetry data. Send to JARL HQ, 1-14-2 Sugamo, Toshimo-ku, Tokyo 170, Japan. JD = Digital mode JA = Analog mode D = All systems off DI = Systems off except CPU and memory The transponders will be off at other times. The actual operating schedule may change due to unexpected situations such as variations in available power. Mode JA Beacon: 435.795 MHz. Mode JD Beacon: 435.910 MHz. /EX