AMSAT-NA AMSAT News Service

November 16, 1997

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Sputnik Model Update

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.]

Station Program Update

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.]

DOVE (DO-17) S-Band

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 0.8 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.]

[Webmaster's note: this item also appears, with an illustration, as a feature article.]

ASUSAT Progress Report

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.]

(No) Weekly Satellite Report

There will be no satellite status information this week due to illness of our regular ANS Editor, BJ Arts WT0N.

We all wish BJ a speedy return to the helm of ANS.

The previous Weekly Satellite Report was dated October 12, 1997.

[Please send your Satellite or News reports to ANS Editor B.J. Arts, WT0N, via e-mail, at bjarts@the-bridge.net or to wt0n@amsat.org]

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This week's AMSAT News Service bulletins were edited by AMSAT Executive Vice President Keith Baker, KB1SF, kb1sf@amsat.org.

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