[amsat-bb] Fw: HF-HF satellite (OSCAR LOCATOR?)

[Bob]

Oh I remember that well -- thanks for bringing that memory back!  And I
know I have mine in a box somewhere.

PDF files of one version are here:  http://www.qsl.net/pe1rah/oscarlator.htm

I seem to recall using the locator to establish a baseline orbit off of
ephemeris data that was received via ARRL CW bulletins (I think I remember
that correctly), then using that baseline to feed into a HP 9830 desktop
calculator which ran interpolation routines to give me a week's worth of
rise data.  The local HP rep loaned me that calculator (I was in middle
school at the time).  My parents had no idea that HP was worth about half
the price of their home back in 1972 (nor did I).

73, Bob, WB4SON



On Fri, May 27, 2016 at 10:38 AM, Ángel Peláez Martínez <amsat-bb at amsat.org>
wrote:

> Hi Bob,
> Rather than vertical, I see a very steep orbit, near to 90deg. It
> resembles a straight line, but it is a curved one indeed, with time
> increment calibration after EQX.
> I hope my explanation be useful.
> Best 73.
> EA4DUT, Angel
>
> Enviado desde mi iPhone
>
> El 27/5/2016, a las 16:09, Robert Bruninga <bruninga at usna.edu> escribió:
>
> >> Sat tracking in the early days was with an AMSAT
> >> OSCAR-LOCATOR (Rotating mylar discs over a global map!!).
> >
> > I just googled and there is only one image of an OSCARLOCATOR I can find.
> > I remember it well, but am confused by this image:
> > http://www.amsat.org/amsat-new/tools/images/oscarlocator.jpg
> >
> > I understand the curved trace.  It crosses near the pole at the latitude
> of
> > the inclination of the orbit.  And I understand the circular plot which
> is
> > angle and elevation from your QTH when placed over your house.  But I do
> > not understand the straight line scale going nearly vertical and labeled
> > RS?  WHy is there no curve to it?
> >
> > And the only other one I found was this:
> > http://www.studiorite.com/oldindex/images/OscarLocator1sm.jpg
> >
> > Which looks like it has the orbits of three different satellites, one of
> > them added on in green marker.  But this one is lacking the AZ/EL circle
> > for the station.
> >
> > Is there a better image anywhere that I can use to justify this "minimum
> > satcom" experiment?
> >
> > And is this how it worked?  You got the daily zero crossing of the
> > equator.  Then for the next 24 hours you could just rotate the plastic
> > overlay by the longitude increment?  ANd increment the time by the
> orbital
> > period?
> >
> > On a trip and without a smart phone, I'd rather do an OSCAR locator then
> > fuss with a PC...
> >
> > Bob, WB4APR
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