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Doppler Lesson answered - Thanks



Thanks to all of you who worked to set me straight.
I've got it. The freq went up even though the bird was still speeding away
from me since the velocity was decreasing in relation to what it WAS. Thus
freq goes up but up, only in relation to what it WAS, not in relation to its
absolute transmitted freq. I'VE GOT IT.
Thanks
I attach what  I think was the best description.
73
Gunther Meisse
W8GSM
May America have a better day tomorrow!

From: Lee KU4OS
"The key point to remember is that the Doppler shift is based on the
relative
speed between the two objects.  What you observed was the shift falling
rapidly to a large negative value as the satellite reached its maximum speed
away from you.  As the satellite climbs from perigee to apogee the velocity
relative to you decreases.  I had to toss a ball into the air a few dozen
times to get this idea fixed in my head.  This decreasing velocity results
in the Doppler shift gradually moving up from its maximum negative value.
The total shift will be still be negative resulting in a lower observed
beacon frequency.  Just not as low as near perigee."



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