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HAMSAT frequencies:
Indian transponder:
Uplink : 435.225MHz to 435.275MHz LSB/CW
Downlink: 145.875MHz to 145.925MHz USB/CW
Beacon : 145.940MHz continue carier signal
HAMSAT frequencies:
Dutch transponder:
Uplink : 435.225MHz to 435.275MHz LSB/CW
Downlink: 145.875MHz to 145.925MHz USB/CW
Beacon : 145.860MHz 12WPM with CW message
Klla: amsat
Hi all! Hamsat launch is now scheduled for 5 May 2005 appx time is 10.22 IST
Members of Amsat India will be at ISTRAC mission centre to experience the pre launch checks , countdown, Tlm and
oribital commands etc. As it will help hams to experience and gain knowledge of such activities specially of their own Hamsat programme.
ISTRAC is the Indian Sat Tracking Centre at Bangalore
Doordharsan TV known as DD ( Govt run TV Ch ) have taken video clipping for an exclusive news story about the HAMSAT.
Hams working sats and interviewed Hams in the amateur sat operations like VU2POP, VU3SXE, VU2GUR have been covered exclusively. This will be aired on 2 or 3 May.
In the mean time a new ham station is setup at ISTRAC apart from the other Ham Stn VU2URC at ISAC.
VU2WMY Mani ( ISAC ), VU2FBS Singh ( ISTRAC ) have been assigned the payload evaluation jobs from ISRO.
Last evening and this morning the new Ham stn at ISRAC was contacted via the AO-51, stns active here were VU2WMY, VU2FBS, VU3TYG, VU2GUR and myself VU2POP.
ISTRAC ham stn was setup by VU2WMY Mani and VU2FBS Singh within a couple of days with the FT-767, FT-726, FT-8800 new G-5500 rotator, 2 UHF, VHF cross yagis, NOVA tracker etc.
They have sucessfully tracked and copied beacon / Tlm of other sats.
We hope the other centres of ISRO too will activate ham stns soon. More than 30 hams are in various centres of ISRO.
At the same time there is excitement around with VU Hams who are gearing up for the Hamsat activity and we hope to hear many new stns coming up on the Sat modes.
Looking forward to the Hamsat.
Best 73
Pop
VU2POP
Secretary
Amsat India regd
Klla: amsat
OSCAR-11 REPORT
18 April 2005
During the period 10 March to 18 April 2005 reliable signals have been received from the 145.826 MHz. beacon, transmitting continuous ASCII telemetry from 18 March to 27 March and from 07 April to 17 April.
At times signals have been weaker than usual, and subject to localinterference (QRN), which has been stronger than usual.
The beacon operates under control of the watchdog timer. Observations haveindicated that the cycle is approximately 10.3 days ON followed by 10.4 days OFF. Assuming that this cycle continues, the beacon should switch ON
around 27/28 April.
When the beacon resumed its transmissions on 07 April, the time stamp in the telemetry was 5.5 minutes fast, ie it had lost approximately 15 minutes since the previous transmission.
By April 13 the onboard clock was just five seconds fast, and it has stabilised at that value. Previously the
clock had been gaining one minute per year during the last 21 years.
Investigations into the behaviour of the +Y axis solar array, suggest that this unit has partially failed. Last year it had been delivering half current for many months.
On December 26th a sudden jump in current was noticed. Since then current in the +Y axis has only been observed on only three occassions this year. Two of these occurred early in the year,immediatly after the beacon switched ON, the other on 12 April.
The next few months will be a challenging time for OSCAR-11, when the solar eclipses start. Since the last eclipse there has been the partial failure of the +Y array, and an unidentified additional current drain on the main 14 volt power bus. This might cause problems if the battery voltage falls below the threshold level of the electronics, perhaps requiring ground control commands to restart the system.
The internal temperatures have varied randomly, up and down by about three degrees C. They are unchanged at 14C, 13C and 20C for the battery,telemetry electronics and command decoder respectively.
At the present time the satellite is in full sunlight, and therefore temperature changes are caused by changes in attitude, and spin rate. The hot external surfaces will cause some nearby internal parts to warm up faster than others. A Solar eclipse predictions indicate that the continuous sunlight will continue until the end of April, when eclipses will start.
The battery voltage has varied between 11.9 and 13.4 volts.
The average voltage was 12.6 volts, similar to the last report.
The period of rotation about the Z axis had been determined from the solar array currents. Values of between 115 and 800 seconds have been observed.On three occasions it was not possible to measure the spin period, owing to the
unusual attitude of the satellite.
Users of OSCAR-11 should note that the date in the telemetry is now advanced by FOUR days.
OSCAR-11 now operates in a default mode, controlled by the watch-dog timer.The satellite transmits continuous ASCII telemetry for approximately 10.3 days on 145.826 MHz., followed by 10.4 days of silence. This regular sequence might be interrupted by ground control, at any time.
At the present time the mode-S beacon 2401.5 MHz. and the UHF beacon 453.025 MHz. are both OFF.
Listeners to OSCAR-11 may be interested in visiting my web site.
The web site contains details about using a soundcard for data capture, and also details about using hardware demodulators. There is software for capturing data, and decoding ASCII telemetry.
There is an archive of raw data for analysis, which is continually being expanded, as new data is captured.
The URL is – http://www.users.zetnet.co.uk/clivew/ If you place this bulletin on a terrestrial packet network, please
use the bulletin identifier $BID:U2RPT108.CWV, to prevent duplication.
73 Clive G3CWV g3cwv@amsat.org
Klla: amsat
Hi All,
Updating you all that the Hamsat ( Vusat ) is packed well and being moved to the launch site about 350 kms away from Bangalore.
VU2WMY Mani is heading the convoy which left this morning 9 AM ( IST ) 13 April 2005. Incidentaly Mani moves most of the sats for over few years and he works in the Thermovac Divn of ISRO Wishing them all a safe and comfortable journey.
Best 73 Pop VU2POP Secretary Amsat India regd.
Klla: www