[amsat-bb] Re: tle repair program
Where in the world are you getting TLE sets that don’t have a checksum? Boo! It would be a one-line change to make NASAWASH always ignore the checksum on input (it always regenerates the checksum on output). With a little more effort this could be controlled by a command-line switch. I can probably generate a quick hack executable for you if needed. Let me know what platform. Or if you’re set up to compile C programs you shouldn’t have any trouble modifying NASAWASH. -Paul On Dec 21, 2013, at 6:05 AM, Jim White wrote: > Thanks Paul. I had forgotten about nasawash. > But it did not help with these sets because it requires a valid checksum and > these have no checksum byte at all. Of course adding an arbitrary byte for > the checksum does not help. > > How about one that reads in tle's without regard to checksums and creates > AMSAT format. Then creates TLEs from the AMSAT format. Perhaps that would > clean them up. . . > > Or something that reads a TLE and creates a valid checksum'd output. . . > > Jim > > On 12/20/2013 5:25 PM, Paul Williamson wrote: >> There’s still NASAWASH, which will do some of that. >> >> http://mustbeart.com/software/nasawash.html >> >> The program could do more to fix spacing problems, but some of what you want >> is impossible or very difficult. The NASA format is pretty compact and >> doesn’t have a lot of redundancy that would make it easy for a program to >> figure out what was meant by some corrupted version. >> >> -Paul >> >> On Dec 20, 2013, at 3:19 PM, Jim White wrote: >> >>> Does anyone know of a program that will 'repair' tle's so they have the >>> right format, spacings, checksums, etc. to assure they will read into >>> various tracking programs? > > ___ > Sent via AMSAT-BB@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@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
[amsat-bb] Re: tle repair program
There’s still NASAWASH, which will do some of that. http://mustbeart.com/software/nasawash.html The program could do more to fix spacing problems, but some of what you want is impossible or very difficult. The NASA format is pretty compact and doesn’t have a lot of redundancy that would make it easy for a program to figure out what was meant by some corrupted version. -Paul On Dec 20, 2013, at 3:19 PM, Jim White wrote: > Does anyone know of a program that will 'repair' tle's so they have the right > format, spacings, checksums, etc. to assure they will read into various > tracking programs? ___ Sent via AMSAT-BB@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
[amsat-bb] Re: *AMSAT* on Echolink
On Dec 17, 2013, at 4:52 PM, Bruce wrote: > it appears that the conference *AMSAT* on Echolink is no longer working. Fixed. The Echolink conference server had to be manually restarted after a reboot. 73 -Paul kb...@amsat.org ___ Sent via AMSAT-BB@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
[amsat-bb] Re: Mailing list commands
Visit the URL at the bottom of every message: http://amsat.org/mailman/listinfo/amsat-bb Scroll to the bottom and click the button "Unsubscribe or edit options" 73 -Paul kb...@amsat.org On Jul 4, 2013, at 10:09 AM, James Luhn wrote: > Can someone tell me how to access the amsat-bb command list. I am in digest > mode at the moment. There are times when I would like to turn off digest > mode. > Thanks, > 73, > -james > W5AOO > ___ > Sent via AMSAT-BB@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@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
[amsat-bb] Re: satellite los footprints
On Mar 25, 2013, at 8:15 AM, Joseph Armbruster wrote: > I can not decide how to implement ground footprints with my google earth > satellite tracker. InstantTrack uses a spherical Earth model for ground footprints. > option 3 : use a digital elevation model and an ellipsoidal model to cull-out > regions that are not visible due to geographic features and project an > irregularly shaped polygon downwards towards the footprint > I believe that local terrain is dominant over any large-scale terrain effect you'd be able to see on a footprint map. It would be worth modeling for AOS/LOS or mutual visibility purposes. 73 -Paul kb...@amsat.org ___ Sent via AMSAT-BB@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
[amsat-bb] Re: Orbitron help please
On Oct 27, 2012, at 9:03 PM, George Henry wrote: > There used to be a program called NASAWASH that would allow you to clean up a > TLE file by specifying, in a text file, which birds you were interested in, > and then running the program against the new TLE file each time you > downloaded it. It would then output a TLE file containing only the sats you > specified. I think it was available for download from the AMSAT files area. NASAWASH is still available at http://www.amsat.org/amsat-new/tools/softwareArchive.php#pc-util or direct from me at http://www.mustbeart.com/software/nasawash.html -- but it doesn't have that feature. It cleans up a TLE file but can't select a subset of the satellites. There are a couple of other old DOS programs still available on the AMSAT web site that do have the feature. Follow the link above and look for EXTRACT or SORTNENG. 73 -Paul kb...@amsat.org ___ Sent via AMSAT-BB@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
[amsat-bb] Re: TACSAT 3 Question
On May 11, 2012, at 12:59 PM, Thomas Doyle wrote: > There must be a better way to detect re-entry than simply than throwing an > unhandled exception. > > You guys seem to be the experts - any suggestions on how to do it ? > It seems to be related to the BSTAR drag value. Some say when the BSTAR > drag value gets "too high" the sat has re-entered or is about to re-enter. I don't have access to SatPC32 internals, but most amateur tracking programs ignore BSTAR completely. BSTAR doesn't even appear in the so-called AMSAT format element sets. It might not be the element you're looking for. Mean motion, the number of revolutions the satellite makes per day, is a nice simple value to look at to detect re-entry, but you can't just look at the mean motion in the element set. That value, like all the other values in the element set, is a snapshot as of the epoch time. Mean motion is actually changing all the time, and we model that change rather simplistically as linear. The value called "Decay rate" in the AMSAT format is basically the rate of change of the mean motion, revolutions per day per day. To compute the value of mean motion at the present (or target) time, you have to multiply the decay rate by the time (in days) elapsed since the epoch time of the element set, and add that to the mean motion from the element set. The threshold to compare against would be the mean motion (number of revolutions per day) of a satellite in circular orbit on the threshold of re-entry. This would be somewhere between 16 revs/day (the familiar 90-minute orbit approximation) and about 17 revs/day (the mean motion a satellite would have if orbiting at sea level). For TACSAT-3 as shown in the current Keplerian elements bulletin, today (day 133 of 2012): 16.45 + (133-121.7) * 0.152 = 18.17 a clearly subterranean mean motion. If you compare TACSAT-3's values to those of other satellites in the bulletin, you'll see that both mean motion (16.45) and decay rate (0.15) are outliers, much higher than any of the others. It might or might not make sense to add a filter like that to a program like NASAWASH. The element set is not invalid in itself. It's just invalid if propagated to the present time. I know I've glossed over a few details in the above analysis. I'm sure one of the experts who actually understands orbital mechanics will correct me if I've fouled it up entirely. 73 -Paul kb...@amsat.org ___ Sent via AMSAT-BB@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
[amsat-bb] Re: AMSAT TLE Question
The nasabare.txt file is created from the 2-line elements bulletins by a little C program I wrote called NASAWASH. http://www.mustbeart.com/software/nasawash.html NASAWASH was written to maximize the compatibility of its output. Its main purpose is to remove any text that isn't part of the two-line element sets, and generate a "clean" file that any program will accept as a completely valid stream of two-line element sets. One of the compatibility issues, historically, has been treatment of "+" plus signs in the calculation of the checksum. Some programs would ignore plus signs, and others would add 2 to the checksum for each plus sign. These two methods are not compatible, except for element sets that don't contain any plus signs. That's why NASAWASH strips them out. To create nasabare.txt on the AMSAT server, NASAWASH starts with the text of the AMSAT bulletin in 2-line format, exactly as emailed out to the KEPS mailing list. I notice that the plus signs are also missing from the elements in the KEPS bulletins, very likely for the same reason. I do not know what exact procedure Ray Hoad uses in generating the bulletins. Did you encounter a compatibility problem with some program as a result of the missing plus signs? I'd be interested in more details. 73 -Paul kb...@amsat.org On May 7, 2012, at 7:01 AM, Thomas Doyle wrote: > I notice that the AMSAT TLE data file > (http://www.amsat.org/amsat/ftp/keps/current/nasabare.txt) > uses what appears to be a "non-standard" format for the BSTAR drag > value in some of the satellites (currently RS-30 HO-68 and SRMSAT). > > When the drag value is 0 the entry in the AMSAT files is 0 0 rather than > the more "standard" 0+0. A drag value of 0 is certainly a curiosity in > itself. > > I realize that we live in a world where a "standard" 8 foot 2 x 4 is 8 feet > long but not > 2 inches by 4 inches so there are possibly many "standards" for TLE data. > > I solved the problem I was having by switching to > (http://www.celestrak.com/NORAD/elements/amateur.txt). > I am still curious as to why the AMSAT file is different. Does AMSAT get > their data > from a different source or did AMSAT create their own standard for > presenting the data. > > thanks, W9KE tom ... > ___ > Sent via AMSAT-BB@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@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
[amsat-bb] Disruption in AMSAT-BB, ANS, SAREX
For reasons we don't fully understand, there was an outage in the AMSAT-BB, SAREX, and ANS mailing lists for the last day or two. I am not sure whether any messages were lost. I think the problem has been dealt with. If you're reading this message, then probably it has. 73 -Paul kb...@amsat.org ___ Sent via AMSAT-BB@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
[amsat-bb] Re: Geostationary Satellites
On Oct 11, 2011, at 3:31 AM, Ken Ernandes wrote: > For those believing in the large space, small satellite theory, the risk of > collision is more real than one might think. It must be, since I would think the risk of collision is so tiny as to be effectively negligible. If we position our satellite halfway between two of those commercial "slots", we have a huge buffer on either side. Now I realize that just measuring distances doesn't capture the whole story, and that orbital dynamics can be non-intuitive, but it boggles the mind that objects spaced that far apart can't be kept from colliding without extraordinary measures. I would say that I'd like to see the analysis to back up the worry, but I doubt I'd understand it. You would, though, so I can only ask whether you have seen the actual analysis and found it compelling. Is there no clever trick of orbit design that can be used to avoid collision? We can afford bigger position errors than the commercial guys can, because we have smaller ground station antennas and no problem with interference crowding. We can even tolerate some long-term motion, since we can certainly accept an occasional adjustment to each ground station. Perhaps these extra freedoms would make it possible to design an orbit that's close enough to geosynchronous for our purposes, but far enough from the commercial orbits to be safe? 73 -Paul kb...@amsat.org ___ Sent via AMSAT-BB@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
[amsat-bb] Re: Geostationary Satellites
On Oct 10, 2011, at 3:03 PM, Ken Ernandes wrote: > 1. There are a finite number of orbital slots at Geostationary. That is > essentially like water front property. I've heard that asserted before, but I question the reasoning. My understanding is that spacing of satellites around the geostationary orbit is dictated by the beamwidth of the ground station antennas. In other words, it's a matter of spatial frequency sharing. The satellites have to be far enough apart that a ground station antenna can illuminate one of them without causing too much harmful interference to the ones in the adjacent slots, after all the expected errors (orbital and ground station pointing) are taken into account. If that's correct, since amateur radio satellite operate on different frequencies from the commercial satellites, there is no conflict between amateur radio satellites and commercial satellites for orbital slots. Where have I gone wrong? 73 -Paul kb...@amsat.org ___ Sent via AMSAT-BB@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
[amsat-bb] Re: ARISSat TLM: Sample rate of Signalink
At 9:17 AM -0500 8/7/11, Alan P. Biddle wrote: >Based on reports I have received, and considerable >experimentation, it seems to be a poor performer in this mode. So far, >nobody has reported success with the unit on any radio. The SignaLink USB worked for me. I copied 39 telemetry frames on the first full-daylight pass here in San Diego using the unmodified SignaLink USB hooked between the 6-pin data port of an IC-7000 and a MacBook Air, with manual tuning, omni antenna, and obstructed horizons. 73 -Paul kb...@amsat.org ___ Sent via AMSAT-BB@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
[amsat-bb] Re: Keps
At 11:46 PM -0500 6/16/11, George Henry wrote: >I used to use a program called NASAWASH. You set up a "mysats" file that >specifies which birds you are interested in, and then you can set up a batch >file that will automatically parse whatever input file you specify (like >nasa.all) and output the filtered results to the filename and location that >you specified. I'm the author of NASAWASH. It doesn't have that feature, though it would be a good starting point for a C programmer wishing to create such a program. If somebody added that feature already, I'm not aware of it (and the version on the AMSAT web/ftp site doesn't include it). Perhaps you're thinking of some other program you used in conjunction with NASAWASH? If you have (or install yourself) a reasonably standard "grep" program (such as the one at http://gnuwin32.sourceforge.net/packages/grep.htm ) you can write a simple batch file script like this, assuming that you've already downloaded the elements from your favorite source to a file named inputfile: nasawash inputfile nasabare.txt grep -A 2 AO-51 nasabare.txt >mynasa.txt grep -A 2 FO-29 nasabare.txt >>mynasa.txt grep -A 2 AO-07 nasabare.txt >>mynasa.txt grep -A 2 SO-67 nasabare.txt >>mynasa.txt The "-A 2" tells grep to output the matching line and two lines following. The NASAWASH step is optional if the file you download contains nothing but the element sets. 73 -Paul kb...@amsat.org ___ Sent via AMSAT-BB@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
[amsat-bb] AMSAT.ORG Host updated
The AMSAT.ORG computer has been upgraded and moved to a new location (still on the UCSD campus). The new location required that a new IP address be assigned. The transition should theoretically be seamless, but some users may have trouble until their network's DNS servers take notice of the update. Unless your network admin has done something unusual, any problems should clear up by themselves within a few days at most. Please report any ongoing problems to me (kb...@amsat.org or p...@mustbeart.com if the problem prevents email from getting through to amsat.org). 73 -Paul kb...@amsat.org >On 08/06/11 17:02, Michael Wolthuis wrote: >> Is anyone else having issues reaching www.amsat.org today? I get a Server > > could not be found error. ___ Sent via AMSAT-BB@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
[amsat-bb] Re: High resolution serial antenna tracking protocol?
At 11:01 AM + 12/27/10, Richard Ferryman wrote: > Does anyone know of a serial protocol that allows fractional degree or minute > data? EasyComm specifies azimuth and elevation to 0.1 degree. There's a copy of that protocol spec here: http://www.mustbeart.com/software/easycomm.txt 73 -Paul kb...@amsat.org ___ Sent via amsat...@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
[amsat-bb] K2BSA/5 to do Sat demonstration 9-11-2010
[Tom is having a problem posting to the AMSAT-BB mailing list, so I'm posting this on his behalf. -kb5mu] N5HYP, Tom will be operating as K2BSA/5 for the 1940Z approximate AO27 pass on Saturday, September 11th at the National Scouting Museum in Irving, Texas as part of a Radio Merit Badge day with a number of Scouts in attendance. Would like a positive demonstration of Amateur Radio Satellite communications so please Call K2BSA/5 and give a shout out to the Scouts on hand. 73, Tom Schuessler, N5HYP ___ Sent via amsat...@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
[amsat-bb] Re: Tracking Software Question
>Can quicktrak or instantrack work with any other antenna pointing devices >other than the KCT? Any information would be appreciated. InstantTrack does. See http://www.amsat.org/amsat-new/tools/ftpsoft.php#pc-rot for some of the drivers currently available that work with InstantTrack. The software interface that InstantTrack uses to talk to rotor controllers is documented here, in case you want to write your own: http://www.amsat.org/amsat/ftp/software/PC/InstantTrack/intspec.txt This interface is based on the way the KCT talks to application programs, but it isn't tied to the KCT specifically. QuikTrak also uses the KCT interface, but it uses it in a different way. Specifically, it preloads tables of positions and then relies on the KCT to execute that program without further help from the application program. None of the InstantTrack-compatible drivers I'm aware of (except the KCT itself) implements that mode, so as far as I know there's no support for QuikTrak other than the KCT. 73 -Paul kb...@amsat.org ___ Sent via amsat...@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
[amsat-bb] Delayed messages on AMSAT-BB
You might have noticed several messages that just came through to AMSAT-BB after delays of up to a few days. Sorry about that. I was unexpectedly away from any usable internet connection and couldn't keep up with the usual maintenance work for the mailing list. 73 -Paul kb...@amsat.org ___ Sent via amsat...@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
[amsat-bb] Re: Bare NASA (2-line) format elements truncated?
At 3:44 PM -0700 7/8/09, Bryan Green wrote: >Minor emergency: the "Bare NASA (2-line) format elements page" appears to be >truncated: > > http://www.amsat.org/amsat/ftp/keps/current/nasabare.txt > >This in turn means that my beloved GoSatWatch software is no-worky! > >Who fixes these things? That's me, I wrote and maintain the scripts that create the files on the FTP site from the Keps bulletins published by Ray Hoad. Thanks for pointing out the problem. The script that creates the nasabare.txt file simply scans the nasa.all file and copies out everything that's a valid 2-line element set. The nasa.all file, in turn, is created by saving everything between the SB line and the /EX line in the bulletin email message, just as a packet radio BBS would have done. The error this week is actually in the bulletin text itself. Many of the element sets in the bulletin were mangled for some reason. You can see this easily by noting that the line lengths are not all the same, as they should be. I have replaced both nasa.all and nasabare.txt with versions from last week's bulletins. When Ray publishes a new set (usually on Friday), they will be replaced as usual with the latest info. 73 -Paul kb...@amsat.org ___ Sent via amsat...@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
[amsat-bb] Re: AMSAT bouncing email redirections?
At 7:44 AM -0400 5/1/09, Robert Bruninga wrote: >Is anyone else having issues with the AMSAT email re-director? Please, reports about problems with AMSAT mail aliases should come to me, not to AMSAT-BB. It's off-topic for AMSAT-BB, since it's not about amateur radio satellites. >Our sysadmin says it is an error at AMSAT >that is not properly carrying through the true originators email >identity or something liket that. We do carry through the originator's true identity. That might be considered wrong by some administrators, but it's the right thing to do. >Thus when the copy gets to our system, it bounces because the >originators address does not match that field which should be >carrying the originators address. Or at least that is how it is >explained to me. When the copy arrives at your system, it bears an originator's address (the true one) that doesn't match the identity of the system doing the delivery. That's a little different than what you said. If you have trouble receiving mail through your mail alias for this reason, and you can't change the minds of your mail administrators about it, then a quick solution is to get another email account somewhere else and use that one to receive your mail alias messages. 73 -Paul kb...@amsat.org ___ Sent via amsat...@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
