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Re: Sat Pc 32 vs IT



>Hello Dave,
>I work FO-29 rather often (also VO-52). When I switch to the satellite while
>it is in range I hear my downlink signal immediately with the right audio
>and  I hear it during the whole pass without any  correction or only little
>corrections of 100 - 200 Hz. CAT control of SSB sats  requires a very high
>precision of the calculated position and speed of the satellite.  If the
>calculations of the program were wrong by 2 minutes or even by 1 minute
>neither CAT control or rotor control would work correctly. The program uses
>the SGP4/SDP4 model for it's orbit calculations which is the most precise
>model available for amateur purposes. With the new version 12.5 you can
>optionally also use the SGP8/SDP8 model, but the results are identical.
>So, please check whether your Keps are new and all settings, particular the
>location, are right.
>
>The AOS/LOS times below the map are calculated in steps of full minutes to
>give you an overview. So, they may differ by  half a minute from the true
>AOS or LOS times. But the real time calculations are updated every second.

I'm talking  actual signal reception times with the antenna indicated 
position, and not any presentation time on the screen....

I don't have a need for CAT control...I maintain a fixed xmit 
frequency, and change it only to agree with the person I'm 
answering... Have used that way for over 25 years, and find it is the 
best way to maintain accurate communications thru an entire 
pass....particularly if more than two on the frequency....Our 
dopplers are all different, so I don't understand any other method of 
accurately them all with CAT??

That may be the difference??  Do I have to use CAT with your program??

It is really no problem as far as communication is concerned, my beam 
width accommodates that small difference, but 2 minutes in a start 
and end time does...

I find nothing in Bob's tracker Jr. to indicate any correction...but 
I may have to look again..

Tnx, Erich, all of us really appreciate your efforts...Dieter and I 
discussed the program many years ago, but I still had IT (with a 
computer that fit the KCT board!!) and now I guess difficult to teach 
an ole dog new tricks!!

Well, I'm old, but I have a lot to learn!!


> > I've checked AOS's and LOS's on FO29 for several times in the last
> > several days.
> >
> > IT is right on, and SAT PC32 is ALWAYS about 2 minutes behind.
> >
> > I can't find it in the documentation, but there may be a way to apply
> > a correction.
> >
> > I use SAT PC 32 with W0LMD'S  Sat Track Jr.  I found nothing in its
> > docs either...
> >
> >



            73, Dave wb6llo@amsat.org
                    Disagree: I learn....

               Pulling for P3E...  


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