October 2011 - AMSAT-BB - mailman.amsat.org

SRMVU Recording 10-19-2011 1032UTC
by Carl Rimmer W8KRF 19 Oct '11

19 Oct '11

Recording of SRMVU (Object D) pass on 10-19-2011 1032UTC. Locator: EN91ck 7 degree max elevation pass. Setup: SatPC32 with LVB Tracker; G-5400B Az/El rotator; Kenwood TS-2000; Antenna M^2 436CP30; ARR MSP432VDG-160 Mast Mounted Preamp. I did notice a change in the change in the Temperature Status during the pass. Initially, it was P but changed to X at approximately the middle of the pass. All other parameters remained constant. 73, -- *Carl W8KRF*

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SRMVU Keps?
by Carl Rimmer W8KRF 19 Oct '11

19 Oct '11

This morning I initially used the lastest Keps for Object B and was able to copy the CW telemetry, however, at Object B's LOS, I was still copying the signal. I switched to Object D and was able to copy CW for another minute or so before LOS which corresponded with the Object D LOS. Hopefully, I will be home for the next pass and will use Object D for SRMVU. The telemetry I copied was SRMVU C Z Z P C C at EN91ck for the 0043UTC (approx) 7 degree pass. 73, -- *Carl W8KRF*

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Re: Technical discussions on AMSAT-BB......"an endangered spec...
by G0MRF＠aol.com 18 Oct '11

18 Oct '11

and for the record, AMSAT-UK has a working design for a 29.45 receiver with 42dB of AGC, crystal filters for the passband, audio buffering / filtering with a bonus 10.7MHz I.F. output.- Just in case you want to add a TX up or downconverter for a linear transponder. - Downside is that although the board is small, it's not the cubesat format Thanks David G0MRF In a message dated 18/10/2011 17:59:20 GMT Standard Time, bruninga(a)usna.edu writes: > I'm curious, as someone who was involved in designing > a nanosatellite. What sort of payloads would be of > interest to the amateur community? The A#1 Killer AP is something we have tried twice on short li=ved missions and which we already have ready for our next mission, (but no launch opportunities) is a PSK-31 transponder.! It is really more than you first think: Please see: http://aprs.org/psk31uplink.html 1) Normal HF PSK-31 uplinks on 10 meters where the Doppler is 14 times less than on the typical UHF downlink. 2) VHF or UHF *FM* downlink. Notice FM. This means what EVERYONE see's on their waterfall is EXACTLY whateveryone else sees. Thus, everyone just jumps into the 3 KHz FM audio bandwidth wherever they see an empty spot and then can even see THEMSELVES full duplex because they are transmitting linear PSK-31 on the uplink on 28.120 while simultaneously seeing what everyone else is seeing on the VHF or UHF FM downlink. 3) Because you see what every one else sees, including yourself, you can SEE your good signal or your bad signal, AND you see how you are shifiting in Doppler and can correct for it. 4) AND because it is full duplex, you TX the entire pass in a steady stream while looking for QSOs in the downlink. We could have 20 to 30 SIMULTANEOUSE QSO's going on at the same time and even be talking to all at the same time. It is the ULTIMATE satellite transponder, because: 1) Full duplex 2) Minimal Doppler 3) You correct for your own Doppler 4) 20 to 30 simultaneous users 5) Free software, no hardware! 6) Vertical 10m antennas are IDEAL power-levelers. When overhead (and 10 dB closer) the signal arrives at the satellite 6 to 10 dB down due to the vertical antenna pattern. It's a win-win-win mission. Our attempt failed on PCSAT2 due to a broken antenna (pre-launch integrators and astronaut handling) and our attempt on RAFT failed due to not enough time available for the tests due to mission conflicts during a shor 5 month mission. Please someone do this. It is TRIVIAL to do. Just combhine a 28.120 PSK-31 receiver and a VHF or UHF FM transmitter. Done. Bob, Wb4APR On Mon, Oct 17, 2011 at 8:55 AM, i8cvs <domenico.i8cvs(a)tin.it> wrote: > Hi All, > > I do remember that when OSCAR-10, OSCAR-13 and AO40 were > alive and well this net on AMSAT-BB was full of technical messages > from W3IWI now K3IO ,G3RUH, G3WDG, ZL1AOX and many others > from wich it was possible to lern the radio technique particularly in the > field of RF and antennas. > > By the way actually with the prolification of Microsats,Nanosats and so on > the above people seems to be not anymore interested on satellite technical > discussions and they abandoned the net. > > Can anyone explain to me why ? > > Thanks for any answere. > > 73" de > > i8CVS Domenico > _______________________________________________ > Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > -- Chintalagiri Shashank Indian Institute of Technology, Kanpur http://blog.chintal.in _______________________________________________ Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb _______________________________________________ Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb

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ARISSat received spectrum
by Roland Zurmely 18 Oct '11

18 Oct '11

Today I copied the spectrum of signals received from ARISSat with an SDR-IQ (and homemade VHF / HFconverter ) and SpectraVue. The frequencies listed are the transmitted by satellite, and Doppler effectis clearly visible in the received signals, with higher frequencies at the beginning and lower at the end of the pass. The noise generated by linear transponder and the return of the transmission that I did in the UHF uplink are clearly visible. The CW-2 signal close to the 1kBPSK telemetry signalcan also be seen, as well as FM transmissions, switching between voice and SSTV. Please see here: http://www.qsl.net/py4zbz/arissat.htm#o 73 de Roland.

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Technical discussions on AMSAT-BB......"an endangered species" ?
by i8cvs 18 Oct '11

18 Oct '11

Hi All, I do remember that when OSCAR-10, OSCAR-13 and AO40 were alive and well this net on AMSAT-BB was full of technical messages from W3IWI now K3IO ,G3RUH, G3WDG, ZL1AOX and many others from wich it was possible to lern the radio technique particularly in the field of RF and antennas. By the way actually with the prolification of Microsats,Nanosats and so on the above people seems to be not anymore interested on satellite technical discussions and they abandoned the net. Can anyone explain to me why ? Thanks for any answere. 73" de i8CVS Domenico

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War EAGLE and congrats to Auburn
by Robert McGwier 18 Oct '11

18 Oct '11

http://ocm.auburn.edu/featured_story/aubiesat.html -- Bob McGwier Facebook: N4HYBob ARS: N4HY

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post-hamfest travel plan for Saturday (22 October)
by Patrick STODDARD (WD9EWK/VA7EWK) 18 Oct '11

18 Oct '11

Hi! After receiving a few comments to my post last week about my trip to the hamfest in Tucson on Saturday (22 October), I have decided to go to the DM51bx/DM52ba grid boundary in southeastern Arizona after the hamfest. I should be there in time for the following passes: AO-51 2133 UTC AO-27 2147 UTC AO- 7 2220 UTC (should be in mode B for this pass) AO-51 2310 UTC Depending on when the hamfest wraps up in the morning, I *may* be able to get out to the grid boundary in time for the AO-27 pass at approximately 2007 UTC. No guarantees on that. I will run APRS as WD9EWK-9 while on the road after the hamfest. You will be able to see my location at http://aprs.fi/wd9ewk-9 among other places on the net. For the AO-7 pass, I tend to park around 145.960 MHz +/-. If I am not working anyone there, I will tune around and try to call anyone else who may be on the pass. I will miss not having FO-29 to work on this trip, but this AO-7 pass should cover most of North America for those wanting to work me in SSB. As with my other trips, and also for the hamfest passes Saturday morning, I will be happy to send out QSL cards. There's no need to first mail me a card - just e-mail me with the QSO details. If you're in the log, I will drop a card in the mail. I will also upload all QSOs to the Logbook of the World system, once I am back home. 73! Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/

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Re: PACIFICON a Blast!
by Clint Bradford 18 Oct '11

18 Oct '11

>> ... Glad I was able to work you during your demo. I hope I didn't sound too goofy. Wasn't that a fun day? All those Scout troops working the FM satellites ... It was GREAT! Clint Bradford, K6LCS

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Re: KickSat - a personal spacecraft of your own in space
by William Leijenaar 18 Oct '11

18 Oct '11

Hi AMSATs, I really wonder if this ever can and will be launched. AMSAT started with eperimental communication systems on the early oscars, and grown into highly complex satellites like AO-40, which was a real achievement for ham radio amateurs. However recent years there is a big trend on CubeSats, of which most are bleep-sats as they only send digital data (as cheap downlink ?). Luckily not all CubeSats are like that :o) At least these CubeSats are under some kind of control, and don't survive very long or can be switched off to minimize RF polution. When I see the idea of 100 chipsats that will all send digital RF signals I wonder where amateur satellite hobby will go into. I see these ChipSats more like RF polution and I believe you can better put your money and effort in designing a real communication satellite. I wonder what is the mission of these 100 chips ? (commercial ? publicity ?) Is there any technology thing we learn from this ? 73 de PE1RAH William Leijenaar

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Re: PACIFICON a Blast!
by Jim Adams 17 Oct '11

17 Oct '11

Glad I was able to work you during your demo. I hope I didn't sound too goofy. Jim Adams - K0BAM

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