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OSCAR-11 Report

                  OSCAR-11 REPORT

                  25 October 2005

During the period 24 September to 25 October 2005 the VHF beacon on 145.826
MHz. resumed transmissions, as expected, on 30 September, sometime between
06:05 and 06:42 UTC passes. Reasonable signals were also captured on the
17:44 pass, later that day.  However by the 16:49 UTC pass on 02 October,
the beacon had switched OFF. Transmissions resumed on 21 October, and
should continue until around 31 October.

The on-board clock continues to show a very large error. Currently it is
19.2394 days slow, having lost six hours while the beacon was last OFF,
ie. between 02 October and 21 October.  When the beacon is ON, the clock is
stable to within a few seconds.

All the analogue telemetry channels, 0 to 59 are zero, ie they have
failed.  The status channels 60 to 67 are still working.

The eclipses have now ended, and the satellite should be in continuous
sunlight for the remainder of this year, and well into next year.  This
should help the satellite to continue transmitting, although continuous
sunlight can cause problems due to excessive temperatures.

The watchdog timer appears to be operating on the 20 day cycle, ie.
approximately ten days ON followed by 10 days OFF. It appears to be
uneffected by problems of the on-board clock. However, poor solar attitude,
and battery problems, may be combining to produce a low line voltage. This
causes the beacon to switch OFF premeaturely, and resets the watchdog timer

The Beacon frequencies are -

VHF 145.826 MHz.  AFSK FM  ASCII Telemetry

UHF 435.025 MHz.  OFF

S-band 2401.5 MHz. OFF

Listeners to OSCAR-11 may be interested in visiting my website which
contains an archive of news & telemetry data. It also contains details
about using a soundcard or hardware demodulators for data capture.  There
is software for capturing data, and decoding ASCII telemetry.  The URL is

If you place this bulletin on a terrestrial packet network, please
use the bulletin identifier $BID:U2RPT114.CWV, to prevent duplication.

73 Clive G3CWV   g3cwv@amsat.org
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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