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[jamsat-news:692] ANS-320 BULLETINS
SB SAT @ AMSAT $ANS-320.01
SPUTNIK MODEL UPDATE
HR AMSAT NEWS SERVICE BULLETIN 320.01 FROM AMSAT HQ
SILVER SPRING, MD, NOVEMBER 16, 1997
TO ALL RADIO AMATEURS BT
BID: $ANS-320.01
The working model of Sputnik continues to "beep beep" its
presence to the world from Earth orbit.
Reports from several places indicate that the working model
Sputnik satellite launched Monday, November 3 from the Russian
MIR Space Station is continuing to provide a readable downlink
signal from its 100 Milliwatt transmitter. For the past two
weeks, the little satellite has been putting out a strong FM
signal on its operating frequency of 145.820 MHz in FM.
Hams and other radio enthusiasts worldwide have now heard the
satellite's distinctive "beep beep" as it flew overhead, some
while using only modest equipment and antennas. The satellite
was built as a joint project by schools in Russia and Reunion
Island, with technical assistance from AMSAT-France.
As the satellite is operating solely on internal batteries, the
downlink signal of the 1/3 scale model of the original Sputnik
is only expected to continue until late November or early
December.
Numerous tracking reports from around the world indicate that
the Sputnik satellite is now flying approximately 2-3
minutes behind and above the Russian MIR Space Station. In
addition, a number of names, including "Sputnik-40",
"Sputnik-40 Years", "Sputnik Jr.", "Spoutnik" (French for
"Sputnik"), "PS2", and "RS-17" have all been associated with
the satellite at one time or another throughout its
construction, birth and on-orbit lifetime.
An updated (13 November) set of Keplerian Elements for both
objects follows:
MIR
1 16609U 86017A 97317.18239798 .00008161 00000-0 10213-3 0 07778
2 16609 051.6539 056.8338 0006645 330.1420 029.9240 15.60771938670286
RS-17
1 24958U 97058C 97317.37650187 .00036370 00000-0 43179-3 0 156
2 24958 51.6590 55.8829 0006516 312.1806 47.8321 15.60798196 1516
[ANS thanks Gerard Auvrey, F6FAO, for his part in providing the
information that went into this bulletin item.]
/EX
SB SAT @ AMSAT $ANS-320.02
STATION PROGRAM UPDATE
HR AMSAT NEWS SERVICE BULLETIN 320.02 FROM AMSAT HQ
SILVER SPRING, MD, NOVEMBER 16, 1997
TO ALL RADIO AMATEURS BT
BID: $ANS-320.02
Paul Willmont, VP9MU, developer of The Station Program,
reports that the program now supports in-band automatic
Doppler correction for SAREX/MIR Simplex and the MIR SAFEX
Repeater. These features have been added in addition to the
program's standard automatic Doppler correction for beacons
and full-duplex QSOs.
The Station Program is a complete ground-station control
program for Windows 3.1, WFW 3.11 & Windows 95. It provides
real-time tracking of satellites with automatic radio control.
It was originally designed especially for users of analog modes
(e.g. voice & Morse).
The Station Program includes support for the German, French,
English, Italian, Spanish & Portuguese languages. Users need
only select their preferred language when running the program
for the first time. Language selection can be changed at any
time in the Options dialog under the Tools menu.
The software supports the Kansas City Tracker, IF-100/AMSAT-DL,
AEA ST-1, DDE Rotor, TrakBox (Rotor), Icom CI-V radios
(via CT-17) & Icom IC-IV (via UX-14/CT-17) interfaces, Yaesu
FT-736R, & Kenwood radios.
The latest version can always be obtained from the AMSAT-BDA
web site:
http://www.amsat.bm
Those interested can also download a paper about the development
of The Station Program (Word6/95 format), from the AMSAT-BDA
web site. This paper gives details on the background of
the project along with its development and current
specifications. The paper was originally presented at the
1997 AMSAT-UK Colloquium at the University of Surrey.
The Station Program comes on three diskettes. Users may
download the latest release from the AMSAT-BDA Web site.
Users can now also download a demonstration version of the
program (serial number 11111-11111-1) for evaluation purposes
only. This version gives full Station functionality, however
no settings will be saved upon exit.
Users are advised that The Station Program requires a
registration number to fully execute. Registration numbers
can be obtained (for a modest donation) from AMSAT-DL, AMSAT-UK,
AMSAT-F, AMSAT-NA & AMSAT-ZL. All proceeds from the distribution
of registration numbers are donated to the AMSAT Phase 3D
Project.
[ANS thanks Paul Willmont, VP9MU, for the information that went
into this bulletin item.]
/EX
SB SAT @ AMSAT $ANS-320.03
DOVE (DO-17) S-BAND
HR AMSAT NEWS SERVICE BULLETIN 320.03 FROM AMSAT HQ
SILVER SPRING, MD, NOVEMBER 16, 1997
TO ALL RADIO AMATEURS BT
BID: $ANS-320.03
Jim White, WD0E, reports that the DOVE's (DO-17) command
operators are attempting to keep the DOVE S-band transmitter
activated for those who wish to test receive equipment on that
band. Jim says one of the team will make an announcement via
AMSAT-BB if the transmitter is temporarily off. At the present
time, it is activated.
The DOVE S-band transmitter puts out about .8 watts to a
bifiler helix mounted on the +Z surface about 1 1/2" in from
one edge. The +Z surface is generally pointed away from the
Earth in the northern hemisphere and toward the Earth in the
southern hemisphere. If users are listening from north of the
equator they should hear deep fades about every 30 seconds or
so as the satellite rotates about its Z axis and the S Band
antenna is blocked by the body of the satellite. Jim says that
below the equator, the signal should appear to be pretty steady.
The data transmitted on S Band is the same as on 2 meters.
It consists of telemetry and a short text broadcast about
every 30 seconds to 1 minute depending on power management
needs. All data is ASCII text. The modulation on S band is
1200 baud PSK.
Decoding the data from this transmitter presents an interesting
challenge because the modulation is about 20dB *below* the
carrier. The carrier suppression failed at launch resulting in
lots of carrier and only low level modulation. Therefore, only
a few packets have been successfully decoded from this
transmitter. This feat was achieved by using a tracking DSP
notch filter to suppress the carrier. That technique requires
a receive system capable of achieving about 30dB signal to
noise to provide modulation about 10dB above the noise, and
a way to eliminate the carrier.
Jim says that a good test of one's S-Band receive capability
is to listen for the buzz of the flags which are continuously
sent. If users can detect the change in the pitch of the
buzz as data is sent, then their receive capability can be
determined to be better than 20dB SNR. In addition, Jim
reports that, "If you can notch out the carrier, run the
resulting signal into a PSK demodulator and decode a
packet, you have a pretty darned good S-Band receive system!"
Tracking the Doppler is also a challenge. Jim says that
it is generally necessary to tune a radio 100 Hz per step
to keep up with the Doppler at closest approach. If the radio
steps in the middle of a packet, that data will nearly always be
corrupted.
Jim also reports that in the near future he may have a sound
card/Pentium software demodulator for use in this mode that
might extract the data without the need for notching out
the carrier. If that works, he notes it would provide an
easier way to test the quality of an S-Band receive system.
Stay tuned to ANS for further updates on this effort.
[ANS thanks Jim White, WD0E, for the information that went into
this bulletin item.]
EX/
SB SAT @ AMSAT $ANS-320.04
ASUSAT PROGRESS REPORT
HR AMSAT NEWS SERVICE BULLETIN 320.04 FROM AMSAT HQ
SILVER SPRING, MD, NOVEMBER 16, 1997
TO ALL RADIO AMATEURS BT
BID: $ANS-320.04
Jim White, WD0E, and others from AMSAT have been working quite
closely with Shea Ferring, overall Program Manager, and a team
of students at Arizona State University on a new student-built
satellite called ASUSAT. During his recent meetings with the
student team, Jim reported that all major hardware components
for the satellite are now built and working and that the space
frame is now complete. The focus of the project at present is
on integration, software development and launch opportunities.
Once successfully launched, ASUSAT will operate on the Amateur
Radio Frequencies in Mode J. It will be capable of 9600 baud
digital operation or it can be used as a bent pipe voice repeater
(similar to AO-27). The satellite will carry two cameras, a
GPS receiver and a group of experimental earth/sun sensors.
It will also be fitted with numerous temperature sensors.
The satellite uses an all-carbon composite structure shaped
into a cylinder 25 cm high and 35 cm in diameter. Stabilization
will be via a student designed and built gravity gradient boom.
Antennas will be monopoles for VHF and UHF. Output power on
70cm will be between 2W and 4W depending on final design, orbit,
and overall power budget. Currently, a Low Earth Orbit is
planned.
Unfortunately, ASUSAT lost its launch slot recently when the
OSC Pegasus rocket that was to have taken it to orbit had to be
modified and ASUSAT's 10 LB mass allocation was used up by
changes to the launcher. ASU officials continue to work with
OSC on launch opportunities and are exploring other options as
well. Jim reports that funding from industry and ASU is
intermittent but continues at a "keep-alive" level. Industry
attention toward the project has increased recently as a result
of awards won by team members at this year's Small Satellite
Conference and other public relations efforts. Jim says that
key industry contacts continue to be productive.
Those who wish to learn more about the ASUSAT project can do so
by visiting their Web site at:
"www.eas.asu.edu/~nasasg/asusat/asusat.html"
Stay tuned to ANS for further developments about ASUSAT.
[ANS thanks Jim White, WD0E, for the information that went into
this bulletin item.]
/EX