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OSCAR-11 Report

                OSCAR-11 REPORT    15 December 1999

During the period 14 November  to 14 December 1999 good signals
have been received from the 145.826 MHz. beacon.

The battery voltage during daylight passes has remained consistently
high. The average value observed was 13.9, with a range of 13.7 to
14.0 volts. The higher value being observed many times.

The internal temperatures have remained fairly constant during
this period. They are now 7.0C and 5.2C for battery and telemetry
electronics respectively.

Ground control reset the attitude correction counters on 17 November.
The Z-axis counter is now incrementing normally, at about 10 counts
per day.  When the counters were reset the spin period was -235
seconds as shown by the WOD described below.  This has slowly drifted
to the present value of -295 seconds. No negative spin correction
pulses have been counted, and only one has occurred in the positive

A new WOD survey of channels 1, 2, 3, 61 (magnetometers) dated 17
November 1999 has been been transmitted. This has a starting time of
15:12:36 UTC.  The WOD shows the unusually low spin period of about
235 seconds, which was current at the time when the survey was

Reports of the mode-S beacon have been received from Carl WA2PIB in
Utah, and Fernando LU1HKO in Cordoba City.  Carl uses a 2ft*3ft
Meyers dish with DownEast pre-amp and converter.  Signals were S3.
Fernando uses a home made converter, with a 60 cm dish. Many thanks
for those reports.

The operating schedule is unchanged.

        ASCII status (210 seconds)
        ASCII bulletin  (60 seconds)
        BINARY SEU (30 seconds)
        ASCII TLM (90 seconds)
        ASCII WOD (120 seconds)
        ASCII bulletin (60 seconds)
        BINARY ENG (30 seconds)

The ASCII bulletin is currently a static message, detailing modes and
frequencies of all the amateur radio satellites.

There  are  additional  status  blocks  after  each bulletin is
transmitted, and between ASCII TLM and WOD.

The mode-S beacon is ON, transmitting an unmodulated carrier, but
telemetry indicates that it has partially failed, and delivering half
power.  This beacon is a useful test source for those testing mode-S
converters, prior to the launch of P3-D. However the signals are very
weak, and there is a lot of Doppler. Users should also note that the
polarisation of OSCAR-11 is LHC. Even if you can't hear OSCAR-11,
your equipment may still be OK for P3-D. Any reports of reception on
2401 MHz.  would be most welcome.  Please e-mail g3cwv@amsat.org.

The 435.025 MHz. beacon is normally OFF.  However it can sometimes be
heard when the satellite is being commanded by ground control, ie.
within range of Guildford, UK.  When the 435 beacon is transmitting,
the 145 beacon is normally OFF.  The data transmitted is mainly

Listeners to OSCAR-11 may be interested in visiting my web site.  The
web site contains details of hardware required and some software for
capturing data, and decoding ASCII telemetry and WOD.  There is an
archive of raw data (mainly WOD) for analysis, which is continually
being expanded, as new data is captured.  Also included are some
audio files, examples of each type of data transmitted by OSCAR-11,
each one plays for about ten seconds.  There are also examples of
mode-S reception.  All the audio files are zipped, so that they can
be played off-line.  These should help listeners identify the various
types of data, and give an indication of the signal quality required
for successful decoding.

The URL is -


If you place this bulletin on a terrestrial packet network, please
use the bulletin identifier $BID:U2RPT44.CWV, to prevent duplication.

73 Clive G3CWV   g3cwv@amsat.org

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