[aprssig] Easy Predicting GO-32 for the mobile!

Robert Bruninga bruninga at usna.edu
Fri Oct 12 20:36:19 EDT 2007


> Using a cheap 1/4 wave (half meter) GP, 
> I finally decoded something from GO-32.  
> The "LIST" in the D7 filled up with 40 
> identical status messages from 4XTECH-12 
> - even the same time tag, right down to 
> the second.  

Interesting.  I think that must have been a fluke in the HT...
Be interesting to know if it happens again.  The pass just
finished was only 25 degrees at my location, but my HT go at
least one position digipeated with its 19" long whip sitting
outside on an A/C unit.

Bob, WB4APR

> 
> ---- Robert Bruninga <bruninga at usna.edu> wrote: 
> > Looks like with the minimum elevation for Mobile reception
of
> > GO-32 being 30 degrees, this translates to usable ground
tracks
> > every 12 degrees of longitude which means we would need 5
> > tables, one for each of these cities:
> > SFO, SLC, Dallas, Chicago and Wash DC.  
> > 
> > These tables and timeswould not change except twice a year
> > switching to/from Daylight Savings time.  For example, here
is
> > the WashingtonDC table (rounded to nearest 5 minutes).
> > 
> > Day1 Day2 Day3 Day4 Day5 Day6 Day7 Day8 Day9 Day1
> > ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
> > 0930 0910 1025 1005 0940 0920 1040 1015 0950 0930
> >      1050                1055
> > 2050 2030 2005 2125 2100 2040 2015 2135 2110 2050
> >      2210 2145                2155
> > 
> > Today is day 3.
> > 
> > If you lived south of DC, then your passes would be 5
minutes
> > later in the morning and 5 minutes earlier in the evening.
For
> > each table, the only info you need is what day you are on.
Then
> > you can count forward or backward in time to predict any
passes.
> > 
> > Remembering that for uplinks, there is an additional pass
100
> > minutes before and after each of those shown as a single
pass.
> > 
> > >> ELEVATION ANGLE:  ... is also easy to infer.  
> > >> The days with double passes are near 30
> > >> degrees each (barely detectible by the mobile).
> > >> The days midway between these lowest peak passes 
> > >> are the highest elevations (75 or more degrees).  
> > >>
> > >> Happy wilderness traveling!
> > >>
> > >> Bob, WB4APR
> > 
> > 
> > _______________________________________________
> > aprssig mailing list
> > aprssig at lists.tapr.org
> > https://lists.tapr.org/cgi-bin/mailman/listinfo/aprssig
> 
> --
> -Al Gerheim
> 
> HP-49G+ Software Page:
> http://members.cox.net/above
> 
> 





More information about the aprssig mailing list