SB ALL @ AMSAT $ANS-204.01 Revised Interim AO-13 Ops Sked HR AMSAT NEWS SERVICE BULLETIN 204.01 FROM WA2LQQ WARWICK, NY July 22, 1988 TO ALL RADIO AMATEURS BT A last minute transponder operating schedule change on AO-13 is required to allow a few more days for spacecraft attitude adjustment. Consequently, Mode B only will be operational for the next few days. Mode B will be on from MA 56 - 210 until the full operating schedule including Mode L is implemented next week. First transponder operation is scheduled to commence at 1500 UTC, 22July88. This means the planned "First Day Club" activities for AO-13 on orbit 81 must be adjusted accordingly. AO-13 Mode B will be activated at approximately 23:26 UTC 22Jul88 and run through approximately 06:19 UTC 23Jul88. (Following is a revision of ANS-201.01) To celebrate the commencement of AO-13 operations, AMSAT-NA is sponsoring an AO-13 "First Day Club" open to ALL satellite communicators and ALL listeners. Awards will be made in three classes of membership to the AO-13 "First Day Club": GOLD CLASS: Requires successful two-way QSO with Official AMSAT "First Day Club" station plus CURRENT AMSAT membership. Gold Class "First Day Club" members will receive an historic, handsome AO-13 QSL card with special "First Day Club" endorsements plus a beautiful AMSAT AO-13 "First Day Club" certificate. SILVER CLASS: Requires successful two-way QSO with Official AMSAT "First Day Club" station but not current AMSAT member. Silver Class "First Day Club" members receive the AO-13 QSL card with "First Day Club" endorsements only. BRONZE CLASS: Requires successful monitoring of Official "First Day Club" station but not current AMSAT member. Bronze Class club members receive an AO-13 QSL card. "First Day Club" operations on AO-13 will run from 23:30 thru 06:19 UTC. "First Day Club" operations will be on the following frequencies: Official AMSAT Station | "First Day Club" Call-In Zone "First Day Club" Downlink | (All participating check-ins downlinks ===========================|================================================ Mode B: 145.957 MHz (USB) | 145.935-145.955 MHz (USB) & 145.835-145.845 CW Here is the roster of Official AMSAT "First Day Club" Stations as of this time: Time Frame Callsign Name QTH 22-23Jul88 =========================================== 2330-0000 WA2LQQ Rip Warwick, NY 0000-0030 WA5ZIB Andy Pearland, TX 0030-0100 K8OCL John Dearborn, MI 0100-0130 WA3WBU John Marysville, PA 0130-0200 KA1M Andy Lowell, MA 0200-0230 AA0P Jack Littleton, CO 0230-0300 K9NO Paul Roselle, IL 0300-0330 (TBD) 0330-0400 W8GQW Wray Tubac, AZ 0400-0430 KL7GRF John Long Beach, CA 0430-0500 VE7XQ Tony Langley, BC 0500-0530 (TBD) 0530-0600 KO5I Doug Paris, TX 0600-0619 WA2LQQ Rip Warwick, NY Those wishing to sign up for AMSAT membership and be eligible for both the QSL card and the "First Day Club" certificate may initiate or renew their membership by calling AMSAT HQ at 301-589-6062 prior to Friday afternoon, July 29. "First Day Club" entries must be sent to AMSAT "First Day Club", P.O. Box 27, Washington, D.C. 20044. Entries must be received not later than August 31, 1988 and must include a business sized SASE. Donations to offset the cost of printing and handling are especially appropriate. Tracking data for Friday evening for AO-13 during this special "First Day Club" event for major regions in the U.S. is included bulletin ANS-202.01. /EX SB ALL @ AMSAT $ANS-205.01 Thousands Attend AO-13 Debut HR AMSAT NEWS SERVICE BULLETIN 205.01 FROM WA2LQQ WARWICK, NY July 23, 1988 TO ALL RADIO AMATEURS BT The AO-13 era began with a roar Friday, July 22, when perhaps thousands of satellite communicators welcomed the newest OSCAR to life. The satellite was first turned on for the general communications operations at 1500 UTC, July 22. The pre-announced operating schedule had to be modified since the satellite attitude had not reached the proper orientation by Friday. The modified schedule had Mode B only running from MA 56 to 210. Satellite controllers indicated maneuvering is slower than expected. This could be due to the higher perigee altitude or the higher inclination of the orbit or both, sources indicate. Controllers suggest the satellite should be properly oriented in a few days. That will allow the full operating schedule, including Mode L, to begin possibly as soon as July 25 they said. When turned on, the Mode B transponder was using its low gain (monopole) receive antenna on 70 cm and was transmitting on its high gain 2 meter array for the downlink. Use of the low gain uplink antenna was apparently mandated by the off-pointing of the satellite. The use of low gain uplink antenna imposed at least a 9 dB penalty in link performance on the uplink and perhaps more. The high gain 70 cm array, three phased dipoles over ground, has a gain of 9.5 dBic. The monopole gain is only about -2 dBi. Later, when the Mode B session ended, the 2 meter downlink reverted to the 2 meter monopole. When the satellite is properly oriented, which will allow the use of the high gain arrays on both Mode B uplink and downlink, the performance should be quite remarkable. The satellite operated on orbit 80 from 1500 UTC to about 1852 UTC (MA 210). Operations over Europe were reported moderate. Apparently word had not circulated widely in Europe that AO-13 was to be turned on that afternoon. The next Mode B operation over the Western Hemisphere was anything but moderate. An army of operators numbering probably in the high hundreds or even thousands pounced on Mode B at exactly 2326 UTC. Among the swishing and ditting, virtually no one could find their downlink not to mention carry on a QSO. If AO-13 wanted to know what it felt like to be pelted with rf from hundreds of 70 cm transmitters at once, its wish was fulfilled at that instant. AO-13's 70 cm receiver AGC zoomed to 12 dB or more it was reported. Fortunately, things got sorted out in an hour or two. By halfway through the nearly 7 hour Mode B episode, many friendly QSOs were under way between old friends who renewed past acquaintances put on hold since AO-10's decline. Towards the end of the orbit 81 Mode B episode, in fact, operating conditions had improved so much that many were obliged to substantially reduce their uplink power to avoid embarrassingly loud downlinks. This was a far cry from the first few minutes of orbit 81 Mode B operations when a blanket of white noise cloaked the entire passband. Many, no doubt, were discouraged by the unpleasant surprise which unfolded with the din at 2326 UTC. These folks will be back when more "regular" operating conditions prevail as indeed seemed the case even towards the end of orbit 81. Mode B users running 10 watts barefoot were comfortably into the transponder late in the orbit. What seemed most remarkable, many users said, was how well the satellite was performing late in the orbit even while under considerable load from many, many users and under the penalty of the low gain 70 cm receive antenna indicated by the PSK telemetry. The outpouring of enthusiasm, despite the initial chaos was heartening according to AMSAT officials. It's plain, one said, we're tapping into a new and renewed user community that's bound to make AO-13 the most popular and productive OSCAR ever built! /EX SB ALL @ AMSAT $ANS-205.02 AO-13 "First Day Club" Success HR AMSAT NEWS SERVICE BULLETIN 205.02 FROM WA2LQQ WARWICK, NY July 23, 1988 TO ALL RADIO AMATEURS BT Once the initial chaos and surge of would-be AO-13 users subsided, AMSAT-NA's "First Day Club" Special Event stations were able to log hundreds of stations. These stations then became eligible for their "First Day Club" awards. "First Day Club" Special Event stations were operated from various locales by AMSAT veterans such as K8OCL, WA3WBU, K9NO, K7RIE, W8GQW, KL7GRF and VE7XQ. Together they logged several hundred stations throughout the Western Hemisphere. Planning for the "First Day Club" special event was hobbled by the uncertainty in the exact "turn-on" day. AMSAT officials said they would have liked to have had more lead-time in planning the event but added the uncertainties experienced are fairly common in the transition of a system from engineering phase to operations phase. When it appeared the turn-on date coincided with the onset of a weekend and would be viewable in the target area, it was decided to go ahead even with the short lead-time. To receive their award certificates and "First Day Club" QSLs, participants need to promptly send an SASE to: AMSAT, "First Day Club", P.O. Box 27, Washington, DC, 20044. Please indicate your callsign and your AMSAT member number, if any, in your letter. This is essential. Without the SASE and your call and member number, AMSAT will be unable to process your award. There is no charge for the award but donations to cover costs are always very much appreciated. Those who do not hold current membership and wish to be eligible for the Gold Class "First Day Club" award have a one week grace period, ending July 29, to get their membership current. Call 301-589-6062 for info. /EX SB ALL @ AMSAT $ANS-205.03 Altitude Slows Orbit Maneuvers HR AMSAT NEWS SERVICE BULLETIN 205.03 FROM WA2LQQ WARWICK, NY July 23, 1988 TO ALL RADIO AMATEURS BT AMSAT-DL satellite controllers say AO-13 will have reached its proper attitude by around July 25. The re-orientation from the second kick motor firing attitude has taken longer than expected. Several factors are at work here they say. The overriding fact is, however, that these types of maneuvers have never been done before under these circumstances and there are quite a number of unknowns that must be dealt with. The attitude control mechanism on AO-13 consists of a group of subsystems which combine to steer the satellite. The sun and earth sensors locate and measure the position of these bodies. The IHU computes spacecraft attitude from these measurements and the magnetorquers, responding to IHU commands, generate magnetic fields. These fields interact with the geo-magnetic field to produce a torque to change the satellite's orientation in space. The geo-magnetic field intensity falls off rapidly with altitude and also varies with latitude. Since AO-13 is at a much higher perigee than originally planned (2500 versus 1500 km), the geo-magnetic field is much less. Thus, the time required for torquing is much more. (The field drops off as the cube of the distance. Doubling the altitude reduces to field eight-fold). Nevertheless, controllers are gaining experience in the existing orbit and are thus better able to predict the time required for a given maneuver. They now say all will be right (well-oriented) by about July 25. If this is achieved, the satellite will be nadir-pointing at apogee. That means that when at its highest point (apogee) the spacecraft's antennas will be pointing directly at earth's center. In the Bahn coordinate system, that will mean BLON (longitude) is 180 degrees and BLAT (latitude) is 0 degrees. (An explanation of Bahn coordinates appears in an upcoming Amateur Satellite Report (ASR), AMSAT's bi-weekly newsletter.) With the attitude of AO-13 on-target in the next few days, satellite controllers expect to implement the full operating schedule including Mode L which was previously announced. The previously announced AO-13 operating schedule, subject to confirmation, is: Mode From Thru Duration MA Minutes ================================================================ Off MA 225 MA 29 61 163.7 Mode B MA 30 MA 97 68 182.5 Mode L MA 98 MA 157 (daily) 60 161.0 Mode JL MA 98 MA 157 (weekends only) 60 161.0 Mode B MA 158 MA 224 67 179.8 Mode S (Mode-S operations will commence when sun angles permit; likely in September RUDAK Concurrent with Mode L /EX SB ALL @ AMSAT $ANS-205.04 Short Bursts HR AMSAT NEWS SERVICE BULLETIN 205.04 FROM WA2LQQ WARWICK, NY July 23, 1988 TO ALL RADIO AMATEURS BT The 7th Annual ARRL Networking Conference will be held on Saturday, October 1 at the Johns Hopkins University Applied Physics Laboratory (APL) Kossiakoff Center. The APL facility is located between Laurel and Columbia MD, midway between Washington and Baltimore. The networking conference will bring together the developers of hardware and software for amateur computer networks and users. Prospective contributors should obtain an author's kit directly from ARRL. The deadline for the submission of camera-ready manuscripts is August 25th. Here is the current AO-10 operating schedule: Through July 31: Mode B MA 25 to MA 235 August 1 - August 15: Mode B MA 30 to MA 240 The satellite will be unavailable for use beginning August 16 because of predicted insufficient solar illumination and reduced battery charge. Here is the FO-12 operating schedule. Mode From (UTC) ---------------- JD 23 1141 DI 24 1020 JD 26 1033 DI 27 1141 JD 30 1100 DI Jul 31 1006 JA Aug 02 1020 D 03 1128 JA 06 0845 D 07 0751 JA 11 0617 D 12 0724 JA 13 0630 D 14 0536 JD Aug 18 0603 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. /EX