Month: April 2016

ÑuSat-1 to Carry AMSAT Argentina Linear Transponder – Launch Scheduled for May 30, 2016

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The Argentinian earth observation satellite ÑuSat-1 will carry a linear transponder built by AMSAT Argentina. The satellite is scheduled to launch on a CZ-4B rocket from Taiyuan Satellite Launch Center in China on May 30, 2016 into a 500 km sun-synchronous orbit with an inclination of 97.5 degrees and a Local Time of the Ascending Node (LTAN) of 10:30.

The AMSAT Argentina U/v inverting transponder, named LUSEX, wiil have an uplink of 435.935 MHz to 435.965 MHz and a downlink of 145.935 MHz to 145.965 MHz. Total power output is 250 mW. There will also be a CW beacon at 145.900 MHz with a power output of 70 mW.

For more information, see the AMSAT Argentina Facebook group.

UPDATE:  A website with preliminiary Keplerian elements and further information is now live at http://lusex.org.ar/

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The AMSAT Argentina LUSEX transponder board. (Photo courtesy AMSAT Argentina)

LUSEX on  ÑuSat-1 – Launch Scheduled May 30, 2016
Uplink LSB 435.965 MHz through 435.935 MHz
Downlink USB 145.935 MHz through 145.965 MHz
70 mW CW beacon 145.900 MHz

OUFTI-1 D-STAR Repeater Satellite Scheduled for Launch Today

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UPDATE: The preliminary keps listed below are incorrect. Use these for the three cubesats until new keps are released.

AAUSAT4
1 00003U 00001A 16116.99330001 .00000000 00000-0 00000-0 0 0018
2 00003 98.2172 124.4782 0152400 241.4610 358.4169 15.02516156 00011

From Stefan Dombrowski, ON6TI: 

OUFTI-1, the first D-STAR repeater in space, is currently on the launchpad in Kourou, French Guiana. The launch is scheduled for Monday, April 25th at 21:02:11 UTC.

On board this Fregat flight, VS14. are Sentinel-1B, Microscope, Norsat-1 as well as 3 cubesats participating at ESA’s “Fly Your Satellite” programme. Those 3 cubesats are:

AAUSAT-4 is an initiative of the University of Aalborg, Denmark and will have as primary payload an AIS receiver to allow tracking of ships. AAUSAT-4 will transmit on 437.425 MHz using CW and the CSP spacelink format. Further information is available on the homepage http://www.space.aau.dk/aausat4/

e-st@r-II is an initiative of the University of Turin, Italy and will transmit a CW beacon on 437.485 MHz. More information is available at http://www.cubesatteam-polito.com/operations/radio-amateurs/

Finally, OUFTI-1 is a cubesat designed at the University of Liège, Belgium. One of its payloads is a complete D-STAR repeater. The initial mode will be a CW beacon on 145.980 MHz. Technical details and the software to decode its telemetry can be found on http://events.ulg.ac.be/oufti-1/radioamateurs/
The CW beacon will transmit periodically for 2 minutes followed by 1 minute of silence.
The AX25 beacon will be turned on later, once the attitude of the satellite has stabilized.
Following timing is expected on Monday, April 25th:

Launch: 21:02:11 UTC (you can watch this live on http://www.esa.int/spaceinvideos/esalive)
Separation: 23:50:24 UTC
Activation: 00:20:24 UTC (Tuesday)

OUFTI-1 and e-st@r-II will start transmitting just in reach of Mexico. 1st pass over the US will be a few minutes later, covering around 00:32:00 UTC the whole US with a very high elevation. The next pass around 02:00:45 UTC will benefit the western half of the US.

The preliminary TLE’s for all 3 cubesats are

OUFTI-1
1 99999U 16116.99345058 .00011869 00000-0 69250-3 0 00006
2 99999 098.1425 127.7912 0173917 231.5709 358.3214 15.00025810000019

Reception reports are welcome on the IRC http://webchat.freenode.net/?channels=#cubesat

jacques_verly_on9cwd_and_amandine_denis_on4eya_with-oufti-1

Phase 4 Weekly Report – April 20th

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From Michelle Thompson, W5NYV:

Greetings all! Here’s our post-Spring-Break Phase 4 Ground engineering report.

First, we have a dual-band feed design update from Paul Wade W1GHZ.

He reports that what he’s come up with looks like it would work pretty well for an offset dish like the DSS dishes, with good efficiency at both bands. Simulation says the isolation from 5.8 GHz to the 10 GHz port is about 80 dB.

Performance plots are attached. He is going to work up a sketch for 3D printing.

He recommends a filter (like the ones in his QEX articles) that can easily provide 60 dB of second harmonic rejection. He believes that the second harmonic from any decent amplifier is 20 or 30 dB down, so that’s at least 80 dB down. Unless the signal is actually inband, a signal that far down won’t hurt.

He added that as for push-pull amps, we may be underestimating the difficulty of keeping them balanced at microwaves. Using a push-pull amplifier as part of the dual-band solution may not provide the performance we need.

Second, there’s plenty of action in the transmitter RF chain with results from measurements at the VHF super conference. Thank you to Eric Nichols, Mike W4UOO, John Petrich, W7FU, John Toscano, Mike Seguin and several others for stepping up to volunteer on this part of the project. We’ll be increasing our use of google forms to coordinate parts of the project, maintaining a list of all the forms on github, and possibly setting up a webpage to increase project findability.

Third, San Diego Microwave Group demonstrated the results of a project that Drew and Kerry Banke have been working on these last couple of weeks. It is the combination of a $4.24 Arduino processor board with a $29 ADF4350 PLL board to provide a programmable fixed LO in the 137-4400 MHz range. Once programmed, this set of off-the-shelf boards comes up on frequency at power up. The programming software utilizes the Analog Devices ADF4350 evaluation software to calculate the PLL data. This is entered by hand in to an Arduino program(sketch) written by Drew. This then is uploaded to the Arduino and that’s it. Kerry reports that the software is easy to use and free. Check out this video report from Paul KB5MU.