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5th May 2005 Indian Space Research Organisation's Polar Satellite Launch Vehicle-C6, carrying India's remote sensing satellite CARTOSAT-1 and a 42.5 Kg micro satellite HAMSAT, blasted off from the Satish Dhawan Space Centre in Sriharikota at 10.22 hrs IST and HAMSAT was inserted to a Near Circular Sun Synchronous Polar Orbit (628 x 621 kms) at 10.41 hrs IST

HAMSAT is a microsatellite for providing satellite based Amateur Radio Services to the national as well as the international community of Amateur Radio Operators (HAMs). HAMSAT will meet the long felt need of the Amateur Radio Operators in the South Asian region  who possess the  required equipment  and operate inthe UHF/VHF band based satellite radio communication.  One of the transponders of HAMSAT has been developed indigenously involving Indian HAMs, with the expertise of ISRO and the experience of AMSAT-INDIA. The second transponder  has  been developed  by a  Dutch  Amateur  Radio  Operator  and  Graduate Engineering student at Higher Technical Institute, Venlo, The Netherlands. It will stimulate technical interest and awareness among the younger generation by providing them with an opportunity to develop their technological projects including

offering a platform. Some of the new technologies being tested in HAMSAT include Integrated Processor based Electronic Bus Management Unit, Lithium Ion Battery and Gallium Arsenide based Solar Panels.

The HAMSAT Micro-satellite is India's contribution to the international community of Amateur Radio Operators. This effort is also meant to bring ISRO's Satellite Services within the reach of the common man and popularize Space Technology among the masses.


AMSAT India has applied for and has been granted an OSCAR number for HAMSAT.

In the future HAMSAT will be referred to as VUSat - OSCAR 52 or VO-52 for short.

Keplerian Elements of HAMSAT are as follows :  HM1
1  28650U  5017B  05315.27248128   .00000086  00000-0  10790-4 0 5904 
2 28650 97.9489 26.9724 0011277 287.8530 252.1488 14.81004948 28144


More Links about HAMSAT :

Amsat India  --


Amsat ---

History of Amateur Radio Satellite

Keplerian Element --  


Dimensions 630mm x 630mm x 550mm Cuboids
Mass 42.5 Kgs.
Orbit 628 x 621 Kms Near Circular Sun SynchronousPolar Low Earth Orbit
Structure Aluminum Honey Comb Structure
Thermal Control Passive Thermal Control
Solar Panels Body mounted Gallium Arsenide Solar Panels
Power Source Lithium Ion COTS Battery
Bus Electronics MAR31750 Processor based providing tele-command, Telemetry, ACS & Sensor Electronics functions
Spin Rate 4 0.5 RPM
Spin Axis 3 Deg.
Stabilization Spin stabilisation with on board autonomy for SRC, MBC and auto SAOC
Sensors Tri-axial Magnetometer and Twin Slit Sun Sensor
Actuators Magnetic Torquers
Communications VHF for TM and TC
Antennae UHF Turnstile, VHF Turnstile
Transponders Mode B (UV)
Transponder Uplink 435.250 Mhz
Transponder Downlink 145.900 Mhz
Ground Station Support Minimal.

When to find HAMSAT over your city in India ?

( Prediction from 06-08-2006 to 05-09-2006 )
















Prediction for Indian Scientific Station at Antarctica

  ( Prediction from 06-08-2006 to 05-09-2006 )





AMSAT India has applied for and has been granted an OSCAR number for HAMSAT.

In the future HAMSAT will be referred to as VUSat-OSCAR 52 or VO-52 for short.

TIPS to Catch HAMSAT / VO-52

HAMSAT or VO-52 is a satellite intended for SSB/CW operation. However as in VU land very few of us can afford multimode VHF/UHF radios we are accessing Hamsat on FM for which it is best to stick to the centre frequencies (435.250 uplink and 145.900 downlink). It is also best to simultaneously monitor your own signals on the downlink using a separate radio. Hamsat requires around 100 watt ERP for solid 59 signals. So if you are using 10 watts RF the recommended antenna gain is around 10 db. However Hamsat or VO-52 have been  accessed  on high elevation passes using 25 watts ERP. If you want to use omni directional antennas you can build a turnstile or an eggbeater antenna which has a dome shaped radiation pattern with circular polarisation. Separate 10 element UHF and 5 element VHF crossed yagis with circular polarisation would give excellent results. Only keep the transmission line loss (particularly on UHF) minimum. Use hardline CATV cable if transmission line is more than 100 feet. Otherwise if you use RG-213 keep the feeder length to around 20 - 30 feet. I have been using a handheld arrow yagi antenna with RG-58U cable of around 1 meter length. Doppler compensation is needed particularly on the UHF uplink where the signal will shift around 10 KHz. So for the uplink it is best to start from 435.240 MHz during AOS and end at 435.260 MHz at LOS and on the downlink start receiving 5 KHz up at 145.905 MHz and end at 145.895 MHz. Currently the VU transponder is on and it has a beacon (continuous carrier) on 145.936 MHz though we have not yet received the beacon from Calcutta / Kolkata.

                                                                                                                                -   By Nilanjan Majumdar (VU2HFR)


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Updated on Thursday, 10 August 2006


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