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

BBC - Hackers plan space satellites
by Trevor . 30 Dec '11

30 Dec '11

BBC News story at http://www.bbc.co.uk/news/technology-16367042 Chaos Communication Congress Dec. 27-30 http://events.ccc.de/congress/2011/Fahrplan/events/4699.en.html 73 Trevor M5AKA

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Chicken Little Contest Update
by Alan P. Biddle 30 Dec '11

30 Dec '11

Now that ARISSat-1 is in its last days, the Chicken Little Contest web site has been updated to include the individual submissions in each category nearest its likely reentry time. www.amsat.org/amsat-new/ARISSat/ARISSatContest You can see how you are doing compared to the competition! It appears that the submissions are sufficiently spread out that we will be able to determine unique winners in each category. However, you can help with this by keeping the telemetry submissions coming. Space Command does not maintain precise Tracking and Impact Prediction (TIP) for minor spacecraft. A small satellite is considered to have reentered when three consecutive tracking stations fail to acquire it, which leaves a considerable window. While the formal last telemetry contest is only open to submission through the telemetry programs, keep listening and note the time and place where you hear it last. After it has been confirmed to have reentered, the last reception including voice and CW, may help narrow that window unless transmissions cease significantly before reentry. Alan WA4SCA

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Re: MMSSTV and ARRISat-1
by Burns Fisher 30 Dec '11

30 Dec '11

I've had good luck with MMSSTV using a Fun Cube Dongle, SDR-Radio and then Virtual Audio Cable to get the audio from SDR-Radio to MMSSTV (all on the same PC). Today I threw in a 4KHz filter from SDR_Radio and that seems to improve the S/N ratio. There was a lot of noise removed by that filter. BTW, I picked up Farrell's license plate quite cleanly around 1800z although I did not get the start clearly enough to lock onto, so the picture has the top cut off. I also noticed some idle in both the telemetry and the FM. A few times I seemed to be getting strong telemetry but got only Kursk frames, or 5 Kursk and 1 satellite. Another time, there was no FM audio for 10 or 15 seconds although there was a carrier. Oddly the telemetry continued, but the CW over on the edge of the telemetry band stopped. I'm not sure I get that, although looking at the code on the satellite might show something. At one point I certainly saw the little guy in low power mode, but the dropouts I mention above are not that. The transmitter was still on.... Burns, W2BFJ > Date: Fri, 30 Dec 2011 14:57:31 -0500 > From: "Zachary Beougher" <zack.kd8ksn(a)hotmail.com> > To: "kp hpjr" <inservice2him(a)hotmail.com>, <amsat-bb(a)amsat.org> > Subject: [amsat-bb] Re: MMSSTV and ARRISat-1 > Message-ID: <SNT111-DS5C3FD0E1BCED394A4AFDBB3920(a)phx.gbl> > Content-Type: text/plain; charset="iso-8859-1" > > I had a similar issue when I first started downloading SSTV, and if I > recall correctly I believe it was because I had the input audio set way too > high (I cranked it down to just about no audio to get a clear pic). If you > have downloaded pictures before from HF and have had success at your preset > audio levels, then I doubt that is the issue. > > Zack > KD8KSN > > From: kp hpjr > Sent: Friday, December 30, 2011 2:41 PM > To: zack.kd8ksn(a)hotmail.com ; amsat-bb(a)amsat.org > Subject: RE: [amsat-bb] Re: MMSSTV and ARRISat-1 > > Zack and others. > > Yes, audio feed is direct as with all digi modes I operate. > > Just had a pass of ARRISat-1 of 45 degrees plus over head. The downlink > into my M2 5 element yagi @ 35 degrees elevation was S-9 plus 10db. A very > good (great) signal. > > 2 times during the pass the SSTV was transmitted. During neither of them > did the program initialize and copy anything. Partway through the 2nd > transmission I forced it into RX Robot-36. All that occured was for it to > stop after about 5 seconds. Again nothing decoded....frustrating to say the > least. I'd like to get 1 photo...HI. > > Using the exact same setting I have had several QSO's now on HF sending > and receiving very clear photos. > > Not sure what else to try. > > N0KK, Kirk > > > > From: zack.kd8ksn(a)hotmail.com > > To: inservice2him(a)hotmail.com; amsat-bb(a)amsat.org > > Date: Fri, 30 Dec 2011 07:48:57 -0500 > > Subject: [amsat-bb] Re: MMSSTV and ARRISat-1 > > > > Hi Kirk, > > > > Like Greg said, ARRISat-1 is Robot 36. I also found that I received the > > clearest pictures when I ran the audio directly into the pc versus > letting > > it pickup the audio from a speaker. I imagine you are probably already > > doing this. > > > > 73! > > > > Zack > > KD8KSN > > > > -----Original Message----- > > From: kp hpjr > > Sent: Wednesday, December 28, 2011 4:35 PM > > To: amsat-bb(a)amsat.org > > Subject: [amsat-bb] MMSSTV and ARRISat-1 > > > > > > GA, > > All the talk about SSTV from this bird got me thinking I'd like to try! > > I downloaded MMSSTV and installed. > > What are the best settings to use in the setup page for decent copy of > > photos from ARRISAT-1? > > I did copy pix on 14.230 after setup as a test run...but on last pass of > > ARRISAT, had wonderful copy of voice beacon but no pictures decoded. > > So wonder what I might be doing wrong. > > Any help appreciated. > > Kirk, N0KK > > > > _______________________________________________ > > 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 > > > ------------------------------ > > _______________________________________________ > Sent via amsat-bb(a)amsat.org. Opinions expressed are those of the author. > Not an AMSAT member? Join now to support the amateur satellite program! > http://amsat.org/mailman/listinfo/amsat-bb > > > End of AMSAT-BB Digest, Vol 6, Issue 699 > **************************************** >

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Fwd: MMSSTV and ARRISat-1
by rogerkola＠aol.com 30 Dec '11

30 Dec '11

If you record the signal first with something like Scanner Recorder (freeware), you can adjust levels or try to "clean" the signal between passes... Plus, you can leave it on during those passes you aren't there for and play it back when you get time. Roger WA1KAT -----Original Message----- From: kp hpjr <inservice2him(a)hotmail.com> To: amsat-bb <amsat-bb(a)amsat.org> Sent: Fri, Dec 30, 2011 1:21 pm Subject: [amsat-bb] MMSSTV and ARRISat-1 GA, All the talk about SSTV from this bird got me thinking I'd like to try! I downloaded MMSSTV and installed. What are the best settings to use in the setup page for decent copy of photos from ARRISAT-1? I did copy pix on 14.230 after setup as a test run...but on last pass of ARRISAT, had wonderful copy of voice beacon but no pictures decoded. So wonder what I might be doing wrong. Any help appreciated.

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HamSatDroid
by Nigel A. Gunn, W8IFF/G8IFF 30 Dec '11

30 Dec '11

My biggest requests would be a) Get it onto the Barnes & Noble Nook marketplace. b) Allow other filename/locations for the keps file. On 30/12/11 19:56, amsat-bb-request(a)amsat.org wrote: > Subject: [amsat-bb] Re: HamSatDroid New Feature Discussion > Message-ID:<D7676DF9-4CBA-49BD-AF7A-20D8F14FC571(a)earthlink.net> > Content-Type: text/plain; charset=windows-1252 > > Some of the requested features "scare" me on your behalf, Dave (grin). > > ? Doppler correction information (1) > ? Footprints (2) > ? Satellite information including frequencies, modes (5)

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ARRISSAT1
by Joe Batty 30 Dec '11

30 Dec '11

Hi guys, Well, I heard the announcement enough times I thought I'd try some CW. So at the 1930 UTC pass today I had the rig set up and a soon as I heard the sat I started calling cq But, not having the kepps Installed I had to keep adjusting the VFO, which was OK. There was some one else doing CW and the copy was a tad fast for me I listened for some time till it went totally out of range, but it was Q5 copy all the way. Being a newbe at Sats this is all new to an old HF guy. Good job Amsat and we certainly look forward to the Fox projects. 73 and and have a great new year Joe KT7E

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ARISSat-1 RADIOSKAF-V KEDR
by Farrell Winder 30 Dec '11

30 Dec '11

All, I am most pleased to advise that ARISSat-1/ RADIOSKAF-V/ KEDR is very much alive and giving an excellent performance through the 475.750/145.930 MHz TRANSPONDER. On the 17:54Z pass over Cincinnati today December 30, I sent and copied my picture. Picture was my ATV call ID used for fast scan. Picture came through all together but does have noise, particularly in the last half. I will send it to the ARISS SSTV Gallery for consideration to post. I hope others will also experiment with CW, voice, and SSTV via the Transponder. 73, Farrell Winder, W8ZCF Cincinnati, Ohio, USA

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ARRISat-1 Activity Report
by GW1FKY＠aol.com 30 Dec '11

30 Dec '11

Hi all, Pleased to report lots of activity on the last two passes of ARRISat-1 over here in Europe today (Friday) Some calls at 1507 hrs PD0RKC, heard you and you were 5 X 8 but dropped to 5 X 5 rather quickly. At 1639 hrs heard ON4GP calling and then in contact with DG1ER, you were both 5X7 prior to the satellite switching off in eclipse. Nice to report the activity as we approach the end on the year and an era for ARISSat-1. Ken Eaton GW1FKY

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PCSAT Status (and needs)
by Bob Bruninga 30 Dec '11

30 Dec '11

PCSAT SUMMARY and SOLICITATION: Our PCSAT recovery attempt this week was unsuccessful this time, but she will be back to normal (intermittent, weak) operation in a few weeks. BACKGROUND: PCSAT is functional a few times a day in the northern hemisphere year round. You can see its telemetry and user activity on http://pcsat.aprs.org . But it dies every orbit in eclipse because it defaults with backup systems turned ON. We can turn them off, but it can only really get enough charge to survive and keep them off during periodic full-sun periods that only happen once or twice a year in winter. PCSAT has a permanent +/-Z magnet for alignment with the Earth's field and a 0.6 RPM spin (solar pressure about Z). The best solar panel is on the -Z (south seeking axis). On the 4 sides are our cheap plastic covered cells and there are no panels on +Z. With a 63 degree inclined orbit, PCSAT enters a full sun period about once every 3 months. PCSAT can be fully operational during those periods and beyond if we can get command and turn off unnecessary redundant loads. The problem is that the times when we get peak sun (peak power) on the BEST panel is when we are also experiencing maximum eclipses. SO we can command easily (peak power available for a packet), but with only 45 minutes charge time, cannot then last through the following 35 min eclipse (minimum average power available). On the other hand, when we have full sun and there are no eclipses (plenty of average power), there is no sun on the -Z face to give us the peak power we need for the few seconds to complete the packet command sequence. What this means is that we really only have one or two days out of the 1 or 2 week full sun windows to get command, and only in winter. Because each orbit as we approach the terminator is getting less and less peak power, but recovering it before full-sun cannot be sustained due to low average power. VOLUNTEER STUDENT PROJECT? Anyway, the offset between the earth's magnetic and geometric poles, suggests there are several degrees of variation in the -Z sun power depending on WHERE the commanding ground station is relative to the time of day and orbit plane with respect to magnetic North. Using simple geometry, I have estimated our best command opportunity from Maryland is when the satellite crosses about 35 deg N latitude and to our east in the morning as the orbit approaches full sun. But I have no comprehensive math model to then predict other optimum times for other potential command locations. DK3WN's ground station in Germany I think, sees a little bit better angle differentiation due to his being perpendicular to the line between the magnetic and geographic poles, but I would like to have a good formal analysis of this geometry to better be able to coordinate our commanding. When commanding, one only gets one attempt per orbit per day. If it fails due to lack of peak power, then the load of the satellites attempted response and RETRIES kills the batteries for that orbit. Anyway, working all of this out with a math model and plots so we can predict these optimum times would be a great benefit to our decade old satellite (the longest operational student project satellite). Bob, WB4APR USNA Sat Lab

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Re: MMSSTV and ARRISat-1
by G0MRF＠aol.com 30 Dec '11

30 Dec '11

Hi Kirk. You need a very good signal to noise ration with that SSTV via FM. I've had OK (ish) pictures with a 3 element beam, but it's not ideal. Try a near overhead pass, it must be a lot closer now than it was 2 months ago when I last tried. 73 David G0MRF In a message dated 30/12/2011 04:21:14 GMT Standard Time, inservice2him(a)hotmail.com writes: GA, All the talk about SSTV from this bird got me thinking I'd like to try! I downloaded MMSSTV and installed. What are the best settings to use in the setup page for decent copy of photos from ARRISAT-1? I did copy pix on 14.230 after setup as a test run...but on last pass of ARRISAT, had wonderful copy of voice beacon but no pictures decoded. So wonder what I might be doing wrong. Any help appreciated. Kirk, N0KK _______________________________________________ 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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