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- **************************************************************************
- * *
- * THIS IS THE WD0GML-AMSAT-ST.LOUIS BBS 24HR 7DAY AT (314)447-3003 *
- * 300/1200/2400 BAUD *
- * Mike Parisey WD0GML SYSOP *
- * Norm Newman NZ0Z Co-SYSOP *
- * *
- **************************************************************************
- SB ALL @ AMSAT $ANS-063.01
- AO-13 OPERATING SCHEDULE CHANGE
-
- HR AMSAT NEWS SERVICE BULLETIN 063.01 FROM AMSAT HQ
- SILVER SPRING, MD MARCH 04, 1989
- TO ALL RADIO AMATEURS BT
-
- OSCAR-13 Spacecraft Attitude Adjustment & Transponder Schedule Change
-
- There will be a AO-13 spacecraft attitude reorientation maneuver taking
- place on March 15 inorder to make adjustments for seasonal changes in
- sun angles. As with all attitude readjustments, there will also be a
- transponder operating schedule change which will accompany this event.
- Effective March 15, 1989 the Operating Schedule for AO-13 will be as
- follows:
-
- Mode B From MA 100 to MA 160
- Mode JL From MA 160 to MA 200
- OFF From MA 200 to MA 255
- Mode B From MA 0 to MA 100
-
- The final Bahn Coordinates for AO-13 after the attitude change will be
- as follows: Bahn Longitude=210 degrees, Bahn Latitude=+5 degrees.
-
- At the present time there is no scheduled Mode S operating time but it
- is expected that this will change after RUDAK testing is finished.
- Listen to the Beacons on AO-13 and AMSAT Nets for the latest
- information on any operating schedule changes. The predicted Bahn
- Coordinates for March 6th are: Bahn Longitude=178.5 degrees, Bahn
- Latitude=-5.1 degrees. The above operating schedule will remain in
- effect until May 3, 1989.
-
- /EX
- SB ALL @ AMSAT $ANS-063.02
- UO-9 ORBITAL DECAY COMPETITION
-
- HR AMSAT NEWS SERVICE BULLETIN 063.02 FROM AMSAT HQ
- SILVER SPRING, MD MARCH 04, 1989
- TO ALL RADIO AMATEURS BT
-
- AMSAT-UK Sponsoring A "Chicken Little" Contest For UO-9
-
- UoSAT-1, Britain's first low-cost satellite focusing on cost-effective
- spacecraft engineering and space education, was launched by NASA Delta
- rocket on the 6th October 1981 at 11:27 GMT into a 554 km 95 minute
- circular, near-polar, Sun-synchronous, low-Earth orbit. Because of the
- relatively low altitude, the residual Earth's atmosphere is gradually
- causing the orbit to decay, and as the orbit lowers, so the atmospheric
- rag increases, causing the satellite's orbit to decay faster. The
- effect is exacerbated by the increasing solar activity due to the Sun
- reaching a peak in its 11-year cycle, as this causes the Earth's
- atmosphere to rise, increasing the drag. The current altitude of the
- satellite is 434 km and it is decaying at a rate of approximately 400 m
- per day.
-
- It is possible to follow the decay of the satellite by monitoring how
- the orbital period (and hence the altitude) changes with time. This can
- be done by monitoring the Doppler shift of the satellite's signals over
- the course of two orbits to note the time between two consecutive
- "Time-of-Closest-Approach" (TCA)s. If you have a receiver with a
- Doppler shift output, plot the Doppler "S-shaped-curves" for two
- consecutive passes -- keeping a careful note of the time. (To see an
- example of what such a curve looks like, see "The Satellite Experi-
- menter's Handbook by K2UBC, page 10-4). The TCA can be found by reading
- off the time for which the curve's slope is steepest. The time between
- the two TCAs is the orbital period, from which the altitude can be
- derived using classical Newtonian mechanics. If you have a 2m
- amateur-radio with a center-frequency indicator, you can identify the
- TCA by noting the time at which the received frequency is exactly the
- frequency transmitted by the satellite (i.e. 145.825 MHz). If your
- receiver has none of these facilities, then the you may assume that the
- TCA is approximately half-way between the "Acquisition-of-Signal" (AOS)
- time, and the "Loss-of-Signal" (LOS) time, providing that your
- radio-horizon is fairly uniform.
-
- If you keep a record of your results over a period of time, you will be
- able to plot the decay curve of the satellite. This will also enable
- you to modify the Mean Motion (1440/Period) of the satellite in the
- Keplerian Element set, so that your orbital prediction programs can
- keep up with the rapid decay.
-
- The competition is as follows: Using any method you choose, predict the
- precise day (UTC) on which UoSAT-1 will decay completely (i.e. burn up
- in the atmosphere). Your entry must arrive at least four weeks before
- the date of your prediction. Please include the following information:
-
- Name:
- Occupation:
- Address:
- Receiving Equipment:
- Predicted Decay Date:
- Brief Note on Method Used:
- Sweatshirt Size (Large/Medium/Small):
- Sweatshirt Color (Grey/White/Light Blue):
-
- Several prizes will be offered such as a UoSAT sweatshirt and AMSAT-UK
- software. In the event of a tie, the winner(s) will be selected at
- random from the correct entries. In the event of there being no correct
- entries, then the nearest date will be declared the winner.
-
- Send in your answers to:
- "UoSAT-1 Orbital Decay Competition"
- AMSAT-UK
- 94 Herongate Road,
- Wanstead Park,
- LONDON E12 5EQ.
-
- /EX
- SB ALL @ AMSAT $ANS-063.03
- LUNAR POLAR PROBE CONFERENCE
-
- HR AMSAT NEWS SERVICE BULLETIN 063.03 FROM AMSAT HQ
- SILVER SPRING, MD MARCH 04, 1989
- TO ALL RADIO AMATEURS BT
-
- AMSAT To Co-Sponsor Lunar Polar Probe (LPP) Conference
-
- AMSAT-NA will co-sponsor the First Lunar Polar Probe conference being
- held in Houston, Texas on March 11-12. The Lunar Polar Probe
- conference is being organized by the Houston Space Society. Additional
- co-sponsors include the National Space Society, Space Studies Institute
- and others. The purpose of the Conference is to bring together
- individuals and organizations who will work together to design, build,
- launch, and track the Lunar Probe. The Lunar Probe series will collect
- information about the moon and promote the exploration, development,
- commercialization, and settlement of space. An AMSAT-NA Representive
- ill give a talk about "Other Small Satellites: The Amateur Radio
- Satellite Corporation." AMSAT members and space enthusiasts are
- encouraged to attend this interesting conference. For more information
- contact Jim Davidson at (713) 643-6373.
-
- /EX
- SB ALL @ AMSAT $ANS-063.04
- Short Bursts
-
- HR AMSAT NEWS SERVICE BULLETIN 063.04 FROM AMSAT HQ
- SILVER SPRING, MD MARCH 04, 1989
- TO ALL RADIO AMATEURS BT
-
- Short Bursts
-
- AMSAT-UK announced recently that they have a new offering in their soft-
- ware catalogue known as SATSCAN-II. This program is written for IBM PC
- compatabiles and will accommodate EGA/VGA modes in full color. This
- program will display satellite positions in a map or in a tabular
- format. SATSCAN-II also provides numerous other useful data to OSCAR
- satellite users. If you would like more information about this
- software package, please send a s.a.s.e to: AMSAT-UK, 94 Herongate
- Road, Wanstead Park, London E12 5EQ England.
-
- There will be a AO-13 Operations Net on March 11, 1989 at 13:00 UTC.
- Courtney Duncan, N5BF, will be the NCS. The downlink frequency for
- this Net will be 145.950 MHz. This Net is designed to give AO-13 users
- the latest operational news about OSCAR satellites. All are invited to
- check-in.
-
- If you would like a quicker update to the Keplerian elements of UO-9
- than are provided from NASA, you are invited to call the NY0T BBS.
- Keith Goobie, NY0T/VE3PDD, is a Captain in the Royal Canadian Air Force
- who is presently stationed at the North American Air Defense Command
- (NORAD) in Colorado Springs, CO. Keith will be putting the "latest and
- greatest" elements for UO-9 on his BBS as he receives them from NORAD
- each day. So for daily updates for UO-9, call the NY0T BBS at (719)
- 637-1375.
-
- /EX
-
- FLASH! FLASH! FLASH! FLASH! FLASH! FLASH! FLASH! FLASH! FLASH! FLASH!
- THE FOLLOWING ADDED BY WD0GML-AMSAT-ST.LOUIS (314) 447-3003 24hr 7day
- 300/1200/2400 baud. This section may have additions through the week!
-
- AMSAT AO-13 OPERATIONS NET:
-
- An Operations Net session was held on AO-13 mode B (145.950)
- from 1546 to 1640 UTC, Saturday 25 February 89. Led by N5BF,
- WA5ZIB and W8GQW checked in and the session quickly evolved into
- a friendly round table. The just completed ZRO test, net
- scheduling (satellite and HF) need for more NCSs, and the
- need for ZRO results publicity were among topics discussed.
- Conditions were fair to good, and would have been better except
- for transponder pumping due to a number of high powered stations
- elsewhere in the passband.
-
- The AMSAT Operations Net schedule for the next several weeks
- is under preparation and will be released to telemail and
- print media shortly. The purposes for the net are:
-
- 1) To use something besides the telephone and telemail to conduct
- some AMSAT communications,
-
- 2) To provide incentive for operators to maintain and use their
- stations for something besides DXing and random contacts, and
-
- 3) To provide satellite operators regular access to AMSAT
- management.
-
- 73 all, Courtney, N5BF
-
- BILL EITEL-SILENT KEY:
-
- The March 6, 1989 edition of Defense News carried an obituary
- notice of the death at 81 of William Eitel, described as a
- radio amateur enthusiast and co-founder of one of Silicon
- Valley's earliest technology companies.
-
- Bill Eitel, WA7LRU/W6UF/W6AY, who with a partner, founded the
- Eitel-McCullough (EIMAC) company, will be remembered by many
- as a long-term, active and enthusiastic member of the
- amateur radio amateur community. An early participant in the
- amateur radio satellite program, Bill was active with the Project
- Oscar group in the 1060's and, as Life Member No. 9, provided
- strong personal and financial support for the AMSAT programs
- in the early 1970's. From 1972 to 1975, he served as chairman
- of the Amateur Satellite Service Committee (ASSC), a coordinating
- body with representation from Project OSCAR, AMSAT, and the ARRL.
- In this position, he undertook a number of initiatives aimed at
- garnering support for the amateur satellite program from the
- highest levels in Government.
-
- Bill was not as active in the past several years due to failing
- health, but continued to take a strong interest in the program.
- He will be missed.