October 2009 - AMSAT-BB - mailman.amsat.org

Handy Sat predictor
by Pedro Converso 27 Oct '09

27 Oct '09

There is a simple one page (or screen) sat predictor for most used birds at http://amsat.org.ar/?f=d After setting your grid locator you get next passes in local time at your location. If using mobile phone or pda navigate to http://lu7aa.org.ar 73, lu7abf, Pedro

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tracking programs
by Jerry 27 Oct '09

27 Oct '09

Hi : I keep reading on the BB that a lot of people have trouble with There satellite tracking programs. I can remember getting on FO-20 every day for years with about 4 operators every day for years without a tracking program at all. Jerry w0sat

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Re: LVB Tracker Interface
by John Kopala 27 Oct '09

27 Oct '09

I used a small radio shack board, a couple of transistors, and 2 DPDT (could be SPDT) 5V relays to duplicate the interface in the G5400B controller in the KR-500, including the DIN plug connection. The LVB tracker should easily interface to the G5400B Yaesu rotor controller. John Kopala N7JK Date: Sun, 25 Oct 2009 17:13:13 +1100 From: "Drew Squires" <asquires(a)bigpond.net.au> Subject: [amsat-bb] LVB tracker To: <amsat-bb(a)amsat.org> Message-ID: <6F5EBD8D450D4E6E8E859CB501D9F379@your85192f2e0d> Content-Type: text/plain; charset="iso-8859-1" Has any Amsat member experience using the LVB tacker with Yaesu G1000DXC and KR-500 rotators? Is it easy?possible?Or impossible ? With thanks Andy VK3AS

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Re: Nova Satellite Prediction Program
by Mark L. Hammond 27 Oct '09

27 Oct '09

Hi Jim, In my book that's easy. SatPC32 73, Mark N8MH > Nova Satellite Prediction Program (Jimcknwire(a)aol.com) > Date: Tue, 27 Oct 2009 12:15:36 EDT > From: Jimcknwire(a)aol.com > Subject: [amsat-bb] Nova Satellite Prediction Program > To: amsat-bb(a)amsat.org > Message-ID: <cfd.64ee15d5.381876a8(a)aol.com> > Content-Type: text/plain; charset="US-ASCII" > > Installed, reinstalled, changed versions- multiple problems with > calculating scripts. What program should I change to? >

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Re: requesting help on a RF link solution (imaginary, ka-band link!)
by Achim Vollhardt 27 Oct '09

27 Oct '09

Hi Samundra, don't see which path loss you assumed, but for 1 AU (149 mill km), I calculate 286 dB @32 GHz. Also 3000K seems much to bad.. assume 300K. So let's add up for 1 AU: 40 dBm (10W) +2x56.4 dBi -286 = -133.2 dBm at RX input 1 Gbit/s assumes 1 GHz bandwidth. 300K is roughly -174 dBm/Hz. 1 GHz = 60dB worse = -116 dBm. So you end up with -133.2 - (-116) = -17.4 Eb/No.. not good. If you add 20dB you end up at 2.6 dB Eb/No. Not brilliant, but close. 20dB means 0.1 AU instead of 1 AU = 14.9 Mill km. I think your result was 4.6E9 m (!), not km.. which is 4.6 mill km. Should be it, if getting back to your assumed 3000K RX. 73s Achim, DH2VA > Date: Tue, 27 Oct 2009 06:03:30 -0400 > From: Samudra Haque <samudra.haque(a)gmail.com> > Subject: [amsat-bb] requesting help on a RF link solution (imaginary > ka-band link!) > To: Amsat-bb <amsat-bb(a)amsat.org> > Message-ID: > <d8c724880910270303k9a3b9cch123289eebcaebf90(a)mail.gmail.com> > Content-Type: text/plain; charset=ISO-8859-1 > > Hi, amsat-bb > > CQ any satellite link budget expert ! > > I'm trying to do a calculation on my own based upon published specs > for the NASA MRO Ka-band experiment, but am getting some unexpected > results for a Ka-band simplex link with Temp=3000K (hypothetical), > operating with a Signal to Noise ratio (unitless) figure of 1.171 > (representing 4.5 dB eb/no with a data rate of 1 Gbps and a bandwidth > of 2.4x109 Hz) > > Question : is 1 gbps not 1x109 bps ? > > Question : if both antennas are 3m parabolic (both are the same type) > with 56.4 dBi boresight gain, what would you think the furthest > distance the link can perform with SNR of 1.171. I have actually used > a padding of 3 dB Eb/No in my link budget, so am not worried about any > further signal loss at first (ok, I should be ..) For the exercise, I > am choosing a 10 Watt estimated output on an arbitrary basis. > > So: > > P_t = 10W > > G_t = 56.4 dBi = G_r , can we assume the same gain for TX and RX on a > parabolic dish ? > > T = 3000K at receiver > > SNR = 1.171 required > > f=32.2 GHz > > B = 2.4E9 Hz, (bpsk, ldpc code 0.5) > > DR = 1E9 bps > > So, I am puzzled why this link budget says the range with these > parameters is equal to 4.644 x 109 Km -- that seems to be a long > distance ! What am I not able to conceptualize. > > > BTW, I know if I send this out, the answer will come to me soon > thereafter, but for education, I would like to know where the problem > in my understanding lies ! > > > Samudra N3RDX > > > ------------------------------

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Re: Nova Satellite Prediction Program
by jeffk13057＠yahoo.com 27 Oct '09

27 Oct '09

if you're using windows try Orbitron. Love it. Good luck Jeff WB2SYK ------Original Message------ From: Jimcknwire(a)aol.com Sender: amsat-bb-bounces(a)amsat.org To: amsat-bb(a)amsat.org Subject: [amsat-bb] Nova Satellite Prediction Program Sent: Oct 27, 2009 12:15 Installed, reinstalled, changed versions- multiple problems with calculating scripts. What program should I change to? _______________________________________________ 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 from my Verizon Wireless BlackBerry

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OT: WARNING! My trouble maker gene is firing
by Bob McGwier 27 Oct '09

27 Oct '09

I am wondering if anyone in receipt of this note is friends with or knows the name of a good high level contact at the ACLU. I have a first amendment case I would like to discuss with them. Please contact me OFF LIST. Bob McGwier -- (Co)Author: DttSP, Quiktrak, PowerSDR, GnuRadio Member: ARRL, AMSAT, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. "You don't need to see the whole staircase, just take the first step.", MLK. Twitter:rwmcgwier Active: Facebook,Myspace,LinkedIn

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Portable satellite terminals for disaster relief
by Daniel Schultz 27 Oct '09

27 Oct '09

I came across this program on the BBC, rebroadcast late Sunday night in Washington DC on WAMU FM: Digital Planet, October 20, 2009 http://www.bbc.co.uk/programmes/p004l2hz This organization, NetHope (http://www.nethope.org), has developed a small $3000 portable satellite terminal for quick deployment to disaster areas, providing voice and internet service through a commercial geosynchronous satellite. They are called "Network Relief Kits". Amsat can pretty well forget about attracting funding for a geosynchronous amateur satellite supporting emergency communications when the capability already exists. It would seem that the only remaining justification for amateur radio in today's world is for the education and self training aspects. I don't know if "self training" as defined in part 97 carries any weight in today's world. There was a time when most engineers started out as hams in their early youth, but today only formal school based education carries any weight with employers and funding agencies. What this will mean for Amsat's ability to launch any future satellites that are larger than a Cubesat and in a higher orbit remains to be seen. Where does Amsat fit in with NetHope and the other non governmental organisations of the world? Dan Schultz N8FGV ---------------------------------- >From the BBC web site: NETWORK RELIEF KITS Network Relief Kits have been designed to provide immediate internet access in remote areas. It is a small portable kit that fits into a back-pack, and has provided a vital aid to workers who set out to help people after disasters. The engineer and journalist, Mike Outmesguine, explains how to build an internet relief kit. BILL BRINDLEY ON NetHope Bill Brindley, the CEO of NetHope, joins Digital Planet to discuss how his organisation developed the Network Relief Kit. Mr Brindley explains the importance of collaboration between non governmental organisations and other big business to further develop tools that will help in the restoration of connectivity to areas that have suffered natural disasters.

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AO-51 in V/US repeater until November 1
by Andrew Glasbrenner 27 Oct '09

27 Oct '09

FM Repeater, V/US Uplink: 145.920 MHz FM Downlink: 435.300 and 2401.200 MHz FM Reports on the S band transmitter would be appreciated. 73, Drew KO4MA

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Re: ITAR is interesting to me
by k0vty＠juno.com 27 Oct '09

27 Oct '09

Greetings All: The Amsat BB is a great source of information we all know: I have a few questions about ITAR that I thought might interest more than I. I tried to be careful of the words I used. 1.) Do all launched satellites that have US components or interests fall under ITAR? 2.) When does ITAR interest begin for a launchable Amateur satellite? 3.) Is software and firmware that is a part of a Amateur satellite at launch fall under ITAR? 4.) Who normally handles University Cube Sat ITAR issues when Amateur frequencies are used? 5.) Who normally handles US Military school Cube-Sat ITAR issues when Amateur frequencies are use ? 6.) When is there no ITAR interest in a Amateur satellite? 7.) Did Suitsat one or two (ARISSaT-1) have any ITAR problems since they are satellites using Amateur frequency? I have more ITAR related questions. Best Regards Joe K0VTY ==================== ____________________________________________________________ Diet Help Cheap Diet Help Tips. Click here. http://thirdpartyoffers.juno.com/TGL2141/c?cp=GQ3735iirkAKr3lhInn7tAAAJ1CmZ…

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