February 2007 - AMSAT-BB - mailman.amsat.org

EME signals ? with WSJT
by Joe Leikhim 25 Feb '07

25 Feb '07

Spacecraft telemetry?? Any recent launches? -- Joe Leikhim K4SAT "The RFI-EMI-GUY"© "Treason doth never prosper: what's the reason? For if it prosper, none dare call it treason." "Follow The Money" ;-P

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AMSAT Journal
by Jeff Davis 25 Feb '07

25 Feb '07

I have been traveling for almost all of 2007 and just have not had time to catch up on the backlog of magazines and many other publications received. Last night I was able to kick back with a cup of coffee and the latest AMSAT Journal (Jan/Feb 2007) and just couldn't put it down until I had consumed every word. The topics covered seemed a good mix of technical and anecdotal account; the writing and editing work is excellent. As AMSAT-NA members, we are fortunate to have such talented people creating a publication that links us all together with the information required to take full advantage of those assets on orbit or under construction. AMSAT-BB can be an interesting place if you are willing to sift through the noise to find a little signal. On the other hand, the Journal is a clear source of concise information and for anyone who is either active or has an interest in satellite operation, it alone is worth the price of membership. How many messages do we see here every month asking the same questions over and over? Those questions are answered, and in detail in the Journal. One example, "Why Can't I Hear AO-51?" by Mark Spencer, WA8SME is a short but definitive treatise on the subject and it really gets to the heart of that same old question asked here many times and in many ways. You want opinions, toss your question out on the -BB and you'll get plenty. You want answers. join AMSAT and get the Journal. "Bravo" and "Kudos" to Ed Long, Bill Hook and all those whose hard work on the Journal is so obviously visible in the end product. Thanks, 73 -- Jeff Davis, KE9V AMSAT-NA | AMSAT-DL ke9v(a)mac.com

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FalconSat3
by Wayne Estes 25 Feb '07

25 Feb '07

I am VERY impressed with the description of FalconSat3 in the AMSAT News Service special bulletin ANS-056.07. With a frame that is roughly 24 inches on a side, it should get enough solar energy for powerful downlinks. Perhaps the downlink will be similar to UO-14. Has anybody heard an estimate of the time duration of the science mission? That is, how long might we have to wait for the amateur payload to be open to the public? Also encouraging is the final statement that FalconSats 4 and 5 will also have amateur payloads. This could return us to the "LEO glory days" when RS-10, RS-12, and UO-14 were all operational with strong downlinks. I wonder if they would consider a Mode A or Mode B linear transponder in one of the future FalconSats... The global shift to code-free HF licenses could result in renewed interest in Mode A. I've always felt that it makes the most sense for AMSAT-NA and AMSAT-DL to focus exclusively on HEO satellites and let universities and smaller AMSAT groups focus on LEO satellites. This is happening in a big way now, thanks to King Abdulaziz University (SaudiSats), US Naval Academy (PCsats), US Air Force Academy (FalconSats), AMSAT-VU (VO-52), and AMSAT-ZL (KiwiSat). Wayne Estes W9AE Oakland, Oregon, USA, CN83ik

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AO-51 tests planned 2-26 and 27
by Jim White 25 Feb '07

25 Feb '07

February 26 and possibly February 27 during the local AM passes over Colorado the AO-51 U band voice transmitter will be off and the S band will be on in digital mode at 38k4 and 78k4. These mode changes are to facilitate the testing of the US Air Force Academy satellite ground station in preparation for the launch of Falconsat-3. Falconsat-3 (FS-3) is another in the series of satellites built at the US Air Force Academy. It is presently scheduled to launch March 8 from Cape Canaveral on an Atlas-V (mission STP-01). USAFA Space Systems Research Center satellites are science oriented and university class. FS-3 carries two space weather plasma detection experiments along with a micro pulse plasma thruster attitude control experiment. The objectives of the program are to do real science and educate USAFA cadets about space systems design, construction, testing, and operations. About 40 senior cadets are in the program each year. Falconsats are operated from the ground station at USAFA near Colorado Springs, Colorado. Once in orbit FS-3’s mission is to collect data from its experiments and provide cadets in the Space Operations major an actual space ops experience. Additionally Astronautics major cadets will analyze telemetry and make operations decisions. FS-3 will perform its primary mission on DOD frequencies with a downlink at 2.220 GHz. Modulation is GMSK at 38k4 or 76k8 bps. All transmissions are in the clear and are AX.25. Additionally FS-3 carries an Amateur transmitter and receiver with a downlink at 435.100 Mhz. Modulation is GMSK at 9k6 with faster bit rates available. The Amateur uplink is in VHF and the frequency will be made available when FS-3 reverts to Amateur mode. After the primary science mission is completed the satellite will be transferred to the USAFA Amateur Radio Club and operated as an Amateur satellite. It can function much like AO-51 in either an FM voice or digital store and forward configurations. During the first few weeks on orbit FS-3 will be commissioned, which includes uploading software and testing all functions. During that time the Amateur payload will be exercised. The primary avionics in FS-3 are from SpaceQuest with additional modules built by cadets and faculty at USAFA and contractors. Software modules are from BekTek, SSTL, and Colorado Satellite Services, with additional software by cadets and faculty at USAFA. The satellite is ‘ESPA class’. The basic structure is a cube about 24” on a side. There is a 3 meter gravity gradient boom that will be extended from the ‘top’ on orbit. On the ‘bottom’ are the pulse plasma thrusters and various antennas including an array of S band patch antennas provided by S&L Technologies of Orlando along with omni antennas for S, V and U bands. The USAFA ground station consists of two complete units with individual masts on the roof of the classroom annex building. Antennas include 6’ and 10’ dishes and Yagis. Rotators are the heavy duty MT-3000 and MT-1000 from M2. The first USAFA satellite, Falcon Gold, went into GTO and measured the strength of GPS signals from well above the constellation. The results showed signal levels were adequate to warrant further experiments and in part lead to the GPS experiment on AO-40 and other satellites. Falconsat 4 and 5 are in the design stages now. Each is expected to carry an Amateur transmitter and receiver in addition to their primary payloads. After launch reception reports will be appreciated. Reports may be sent to: fs3reports(a)coloradosatellite.com Jim White css(a)coloradosatellite.com

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EME signals ? with WSJT
by Mineo Wakita 25 Feb '07

25 Feb '07

EME signals ? 144.104 MHz JT65B mode Feb 25, 21:53 JST, 2007 Feb 25, 12:53 UTC, 2007 http://www.ne.jp/asahi/hamradio/je9pel/70225eme.mp3 (199kB) http://www.ne.jp/asahi/hamradio/je9pel/70225eme.wav (877kB) Equipment ZQ-81 (LAMBDA): 144 Cubical Quad, 8ele x 1, 13.0dBd GPA-2020 (ANTEN): 144 PreAmp, RFgain 20dB 8D-FB (Fujikura): 12m WSJT 5.9.6 http://pulsar.princeton.edu/~joe/K1JT/ http://www.vhfdx.de/wsjt/ JARL http://www.jarl.or.jp/Japanese/2_Joho/2-6_stations/sked.pdf --------------------------------------------- Name: Mineo Wakita / JE9PEL, JAMSAT member Mail: ei7m-wkt(a)asahi-net.or.jp URL : http://www.ne.jp/asahi/hamradio/je9pel/ QTH : Yokohama Japan, GL:pm95tj Date: Feb 26, 2007 ---------------------------------------------

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Re: AMSAT-BB Digest, Vol 2, Issue 135
by Gary McKelvie 25 Feb '07

25 Feb '07

Hi to John and the List, I'm certainly taking onboard what people are suggesting :) I think I also have said that I have a crossed 70 cm 19 element Yagi from before, as well as rotators to enable both azimuth and elevation control of the antennas so i'm starting to think even with the fixed polarization of the 9/19 element Tonna i will need to use the elevation rotator. Now to my next though If I have this right the LEO's use 70cm as the down link and the 2m side as the uplink, so to my way of thinking I need the most gain really on the down link side. So would it be better to have a small 2m Yagi crossed about 4-5 elements. The 847 output on 2 and 70 is variable 5 - 50 watts on both bands all modes. If I was to go this way I would also look at circular polarization on the antennas. I would also be looking at using a duplexer to enable me to use one feed line which again would make the XYL happier as where the antennas will have to go when up is across the back lawn. I understand that will impact on the performance of the system but I willing to accept that :) So the question is RHCP or LHCP? Which is best or do I need to be able to switch from one to another? As you can see I don't have a fixed idea on the station as yet. I find it easier to talk it through with people first then go get it up and running :) So thank you all for listening to me and the help as well. 73 Gary At 01:45 23/02/2007, John Kopala wrote : >The beams with their inherent gain will enable working satellites on more >passes and lower elevations. You may experience some fading with fixed >polarization, but the gain of the antennas may compensate for that. Some of >the satellites do require a little more power to get into, but your setup >should be more than adequate. Gary McKelvie G7USC Web : www.garym.org.uk Mobile : +447968501863 MSN Messenger : gm7usc(a)hotmail.com So Long and Thanks for all the Fish

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Next P-POD CubeSat launch scheduled for 27Mar07
by Ralph Wallio, W0RPK 25 Feb '07

25 Feb '07

Kosmotras has advised CalPoly CubeSat Management that their next DNEPR launch is scheduled for 27Mar07. Payloads will include CubeSats, EgyptSat and SaudiSats. The launch will include 3 CubeSat P-PODs with assignments as follows: P-POD A CalPoly PolySat CP4 (OSCAR) AeroSpace AeroCube-2 Boeing CSTB-1 P-POD B CalPoly PolySat CP3 (OSCAR) University of Louisiana CAPE-1 (OSCAR) Universidad Sergio Arboleda (Colombia) Libertad-1 (OSCAR) P-POD C Tethers Unlimited MAST (triple-cube) More information including OSCAR frequencies and modes will be updated at http://showcase.netins.net/web/wallio/CubeSat.htm. CalPoly's CubeSat web page is available via http://cubesat.atl.calpoly.edu/ (updates expected). TNX es 73 de Ralph Wallio, WØRPK W0RPK(a)netINS.net http://showcase.netins.net/web/wallio/ Hubbert's Peak - The Mother of all Perfect Storms

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status reports
by john heath 25 Feb '07

25 Feb '07

Hi, If you havn't yet found this site then its worth a look. http://oscar.dcarr.org/index.php You can see up to date reports on a whole range of Oscars and upload your own reception reports. If KD5QGR is monitoring this list I have a request please. Can you add Peheunsat-1 and Genesat-1 73 John G7HIA

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ISM question
by Dan Kuester 24 Feb '07

24 Feb '07

Hi all, I'm part of a team looking at building a cubesat using an MHX-2400 modem, the same 2.4GHz ISM-band modem used in the cube sat kit. We're building both a new Earth station and a satellite - both are using a matching pair of these modems. We've got the technical logistics worked out, but we've had some difficulty understanding how the regulations work. Unfortunately I'm not experienced enough yet to understand how FCC sections 15 and 25 interact with one another. Can anyone offer any advice on this? What kind of regulatory paperwork do will need to fill out, and with who? Cheers, Dan Kuester

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help with satpc32
by Nick Pugh 24 Feb '07

24 Feb '07

Hi All I am running satpc32 under xp ,1.3 ghz processor and a 512 meg of ram. When I have 2 or 3 other programs running in the back gourd I get error 105 on satps every 15 to 20 seconds. help thanks nick

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