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Re: ka0yos wrong again! Phase / MA

Gary \"Joe\" Mayfield wrote:

> Phase and MA are the same.   Both are the orbit divided into 256 (0-255)
> parts.  There is no conversion factor.  If the transponder is to be switched
> on at MA 135 it is the same as being switched on at Phase 135.  I apologize
> to anyone I confused or mislead.  I am also a little surprised no one
> corrected me.

Nobody corrected you because you weren't acually *wrong*. Anomaly, be it 
mean *or* true, is properly expressed as an angle, usually in 
degrees--hence an orbit divided into 360 units, 0-359.

"Phase" is a name invented for the 0-255 system that suits our 
increasingly binary lives a bit better. But people very commonly refer 
to "MA" when they're using the much more common 256 unit system, even 
though it's technically incorrect. If you started using MA in degrees 
everybody would be confused.

*Except* in Keplerian orbital elements, where the third element of the 
second line of a NORAD-format two-line element is called "mean anomaly", 
and is in degrees, as it "should" be.

So your only mistake was in not following conventional usage, which is 
technically wrong.

Now let's talk about how squint angle for AO-40 is 180 degress off from 
what it would be for ao-10...if I have this right when my SatTrack tells 
me the squint is 180 degrees, the high-gains are pointed right at me. :-)

73 de Maggie K3XS

-----/___.   _)   Margaret Stephanie Leber    / "The art of progress  /
----/(, /|  /| http://voicenet.com/~maggie   / consists of preserving/
---/   / | / |  _   _   _    `  _AOPA 925383/ order amid change and /
--/ ) /  |/  |_(_(_(_/_(_/__(__(/_  FN20hd / change amid order."   /
-/ (_/   '  K3XS  .-/ .-/    ARRL 39280   /___ --A.N.Whitehead ___/
/____ICQ 7161096_(_/_(_/__AMSAT 32844____/ <maggie@voicenet.com>

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