[amsat-bb] Re: O/OREOS TLE errors ?

[PA3GUO]

Hi Ryan

Thanks a lot for your detailed reply.

Would you be so kind to share that spreadsheet (XLS?) with me ?
In the coming days I really need (well, would higly appreciate) to 
have working TLEs - especially also for Nanosail.

Best of course would be if the O/OREOS/Nanasail team could fix this prior
to posting them on the web :-)

Thanks
Henk


---- Ryan Caron <rcaron at gmail.com> schreef:
> The O/OREOS TLEs consistently do not have valid checksums (last digit of 
> each line). I submitted a comment about this on their website but I have 
> not heard back. The correct checksums are 2 & 3, and not the 6 & 5 that 
> is listed.
> 
> If, by the time you read this, the posted TLEs are not 6 & 5, then the 
> TLEs have been updated and you'll have to generate new checksums. The 
> formula is a sum of all numerical characters on the line, including the 
> line number, treating minus signs as a one and everything else (letters, 
> +, spaces) as a 0. Then take modulus 10 of the sum (i.e. last digit of 
> the sum). Look it up on wikipedia for more details.
> 
> I've made a spreadsheet to fix this, but it is still a manual operation 
> for me (got to write a script at some point). Some programs disregard 
> the the checksum, which is why HRD & the website still work and your 
> tracking tool doesn't. Predict/GPredict, my tools of choice, require 
> valid checksums, making proper TLEs a pet peeve of mine. I don't know 
> what NOVA's up to.
> 
> In terms of "swarm spread" (i.e. how small delta-V between spacecraft 
> that shared the same ride, which in this case is just done by compressed 
> springs, translates into spatial differences), 35 minutes of separation 
> is pretty high for just 10 days after launch. With all the latest TLEs 
> from the three websites, I show O/OREOS being 3.5 minutes ahead of RAX, 
> and RAX being a 1.33 minutes ahead of FAST1/2.
> 
> Ryan, KB1LKI
> 
> On 11/30/10 4:54 AM, amsat-bb-request at amsat.org wrote:
> > ------------------------------
> >
> > Message: 4
> > Date: Mon, 29 Nov 2010 22:55:16 +0100
> > From: PA3GUO<pa3guo at upcmail.nl>
> > Subject: [amsat-bb]  O/OREOS TLE errors ?
> > To:amsat-bb at amsat.org
> > Message-ID:<19767175.1291067716437.JavaMail.root at viefep21.chello.at>
> > Content-Type: text/plain; charset=utf-8
> >
> > Dear all,
> >
> > I keep on having troubles with the O/OREOS kepler sets.
> > RAX and the others are fine.
> >
> > With todays version (as from the O/OREOS dashboard on the web)
> > - NOVA gives O/OREOS just a bit behind RAX
> > - HamRadioDeluxe give O/OREOS 35 minutes behind RAX
> > - The O/OREOS web (dashboard graphic) shows O/OREOS 35 minutes behind RAX
> > - My private antenna tracking tool does not recognize the keplerset of O/OREOS
> >
> > Anyone else has experienced this (and maybe even a solution) ?
> > Henk
> > --
> > Henk, PA3GUO
> >

--
Henk, PA3GUO