TURKSAT-3USAT to launch with V/U Linear Transponder

Preparing for TAMSAT linear transponder tests

Preparing for TAMSAT linear transponder tests

TURKSAT-3USAT is a three unit CubeSat built jointly by TURKSAT and the Istanbul Technical University (ITU).

Members of AMSAT-TR (TAMSAT), the Turkish Amateur Satellite Technologies Organisation, have designed and implemented a V/U linear transponder for the satellite to provide amateur radio SSB/CW communications. The transponder input is 145.940-145.990 MHz and the output is 435.200-435.250 MHz, there will be a CW beacon on 437.225 MHz.

TAMSAT V/U Linear Transponder Test

TAMSAT V/U Linear Transponder Test

The VHF/UHF transponder and all other subsystems, except the stabilization, are doubled for redundancy. Where possible, both COTS systems and in-house development are employed.

The power is provided using solar panels and lithium polymer batteries together with super capacitors. Satellite stabilization is accomplished using passive magnetic attitude control system with hysteresis rods. There is a camera payload to take images of the Earth.

TURKSAT-3USAT is expected to launch on April 26 at 0413 UT on a CZ-2D rocket from the Jiuquan Space Center into a 680 km Low Earth Orbit (LEO). The satellite has a de-orbiting system which will make it re-enter the atmosphere at the end of its operational life.

On February 9, 2013 TAMSAT President A. Tahir Dengiz, TA2T, and Vice-President Barış Dinc, TA7W, were at the laboratory in the Istanbul Technical University (ITU) where tests were carried out on the transponder.

TAMSAT team celebrating a successful test

TAMSAT team celebrating a successful test

Further information and pictures of the preliminary testing of the V/U transponder are at
http://www.tamsat.org.tr/tr/turksat-3usat-is-almost-ready/

Read the paper TURKSAT-3USAT: A 3U Communication CubeSat
http://www.nanosat.jp/images/3rd/pdf/%5BNSS-03-0409%5D_TURKSAT-3USAT_A_3U_COMMUNICATION.pdf

Read more on the TAMSAT website which can be seen in Google English at http://tinyurl.com/TurkeyTAMSAT

Facebook https://www.facebook.com/tamsat.amsattr

Twitter https://twitter.com/tamsat_tr

YouTube http://www.youtube.com/user/tamsatvideo

ISRO plans SARAL and Amateur Radio satellites launch for February 25

AAUSAT3 Flight Model and Engineering Model - Image credit Aalborg University

AAUSAT3 Flight Model and Engineering Model – Image credit Aalborg University

The Hindu newspaper reports that the first launch of the year by the Indian Space Research Organisation (ISRO) will be the PSLV-CA (PSLV-C20). It will carry the ocean study spacecraft SARAL as well as satellites carrying amateur radio payloads. The launch into a 785 km orbit is currently planned to take place on February 25.

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Amateur Radio TV and CW Beacons for ISS

The minutes of the ARISS International Monthly Teleconference for June 19 carry this report on the status of the amateur radio equipment for the ISS Columbus module.

Kenneth [N5VHO] reported that an onboard power issue somewhat impacted ARISS radio operations. The air purifier for the ATV [Automated Transfer Vehicle] has needed to be plugged in, recently, in the Service Module (SM). The ARISS radio in the SM was turned off while the purifier was being used. The radio is turned on by the crew for school contacts and when the crew gets on the air for random contacts, as Astronaut Kuipers has done in the past few weeks. The ATV will be docked at the ISS until late September.

Gaston [ON4WF] said the HamTV project is progressing. There have been discussions with ESA about the possibility of adding extra units to the HamTV transmitter that is being developed by Kaiser Italia. This is acceptable in as far as the KI unit under construction does not need to be modified.

A so called “Video Beacon” will be added externally to the HamTV unit. This beacon will allow automated DATV transmissions more or less permanently. The content of these DATV transmissions will be uploaded from the ground through existing channels and transferred to the Video Beacon on request. This function will also be used for educational purposes. Moreover, astronauts could record footage and load it into the Video Beacon for automated transmission.

Another additional unit will be a CW beacon transmitter delivering a small band low power signal (100 mW) on a frequency nearby the HamTV frequency. This beacon will transmit permanently and use the second ARISS L/S-band antenna. This offers ground stations signal reception with large S/N margins, facilitating antenna tracking and signal acquisition, especially at the beginning of a pass. The CW Beacon will transmit telegraphy signals, alternating its identification (call sign), a continuous carrier and possibly some telemetry comprizing onboard parameters (temperature, pressure, humidity, ambient sound level, etc.).

Lou W5DID suggested that we may be able to power it from the packet module already on the ISS, making it simple to operate.

ESA is being asked to address the cost of the Safety Package and testing such as EMI tests and outgassing tests for these additional units, but development and manufacturing will be supported by ARISS. A cost estimate is being developed for our team to build the units. A funding campaign will be set up to collect donations to cover the cost.

Amateur Radio on the International Space Station (ARISS) http://ariss.rac.ca/

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HO-68 CW beacon with Funcube Dongle and Arrow antenna

Reception of the HO-68 (XW-1) satellite beacon using the Funcube Dongle receiver and an Arrow II hand-held yagi antenna. Quisk software defined radio receiver running on Ubuntu Linux 10.10 64bit.
I was located indoors pointing the Arrow out through the window (and Doppler tuning with left hand, hence the high pitch 😉
The peak was around 52 deg elevation, range 1400 km. The CW beacon transmitter is 200mW RF.

The Funcube Dongle is a USB stick SDR receiver for 64 MHz – 1.7 GHz by Howard Long G6LVB, see http://www.funcubedongle.com/

Video recorded by Alexandru Csete OZ9AEC

Receiving PRISM CW satellite beacon with FUNcube Dongle Pro

watch?v=gVCiDziXLWc

This video demonstrates the AMSAT-UK FUNcube dongle pro receiving
CW signals from PRISM.

The You Tube video has the following comment by the publisher

“I was only using a vertical VHF/UHF antenna hooked up to the FUNcube Dongle Pro. Software is SDR-Radio and HRD Satellite Tracker, both by Simon HB9DRV”

You can purchase the FUNcube dongle pro HERE

Masat-1 satellite

Masat-1 satellite will use the amateur radio frequency band to downlink telemetry data. The downlink data will not be encrypted, so everyone will be able to receive it, decode and process.

Frequency bands employed

  • Earth-to-satellite (uplink) on 2 m
  • Satellite-to-Earth (downlink) on 70 cm

Masat-1 callsign: HA5MASAT
Satellite’s telemetry transmission frequency: 437.345 MHz +/- 10 kHz Doppler

 

The reason for the Doppler shift is the orbital velocity of 7-8 km/s, as when a transmitter is getting closer to the receiver the received signal’s frequency is shifted upwards, and when the transmitter is getting away from the receiver the received signal’s frequency is shifted downwards.

The satellite’s modulation scheme: (A1A) CW and 2-GFSK with 625 Hz frequency deviation (CW is clocked at 120 characters/minute, which is well-audible by ear).

Data rate of the 2-GFSK digital packets: 625 or 1250 bits/second (a PC with sound card and demodulation SW is required)

 

Minimum list of devices required for receiving Masat-1

  • antenna suitable for the 70 cm band (in open air, pointed towards the sky)
  • tuneable radio receiver with 70 cm SSB USB mode, such as FT-817, FT-897D, TS-2000, etc.
  • PC with sound card, running the telemetry packet decoder SW in JAVA environment. The demodulator software can be downloaded from this website.

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