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on 8/14/00 11:06 PM, Butterfield at Fiagoy@email.msn.com wrote:

> I think the main thing to remember is that you don't need a lot of power
> on the uplink to hit the bird and get through.   I think there is a problem
> today in that instead of timing our transmissions and getting in that way
> many operators are putting more power to the bird which just slams everyone
> else especially those working QRP with an HT.   I have personally worked
> stations from Hawaii to the Bahamas and from Alaska to southern Mexico with
> just an HT and 5 watts or less.
> If someone wants to have a preamp on their downlink that's fine -- go
> for it --  but PLEASE keep your transmitter power down so you don't trounce
> on the many of us working the birds with less power.

I disagree.  If I run 2 Watts to my 40 elements on 432, I'll get in better
than someone running 10 Watts to an omni.  Power is not necessarily the only
thing that matters.  That's what I mean about simplistic thinking on the FM
birds.  I am not meaning to insult you hear, but it is simplistic to say
that people running too much power is why the FM birds are QRMed.  If people
operate PROPERLY, then who cares how much power you have!

When operating satellites, it isn't just a matter of power.  I live in the
mid-west.  Say I want to talk on a bird when it's on a pass off the coast of
California.  For me, that could be a very low angle pass.  It could be
difficult to hit.  So I point my beams and crank up my power in order to get
through trees, obstructions, etc.  But let's say you live in California.
For you, it might be a nearly overhead pass.  You are MUCH closer to the
bird than I am.  You signal from your HT on a couple of Watts will probably
get through better than my 50 Watts.  You'll capture the bird before me.

If we consider the distance between you and me to be 2000 miles and the
distance between you and the bird when it is overhead is 400 miles, than we
can compute a rough estimate of the distance from me to the bird.  I say
rough because I am going to assume a linear system here.  In real life, it's
a spherical system.  The distance from me to the bird is the hypotenuse of a
right triangle in my "linear" system.  Therefore from the Pathagorean
theorem:  a^2 + b^2 = c^2, the distance from me to the bird is: 2039 miles.
I have over 5 times the distance between the bird and myself than you do.
The far field of an RF signal falls with a rate inversely proportional to
the radius from you (1/R).  If you and I transmit with the same power, my
signal at the bird will be much, much less than yours.  And if I run more
power, it still might be less.

So folks, get off the fact that people that run more power automatically get
into the FM birds.  IT JUST ISN'T TRUE!  This is simplistic terrestrial
thinking drilled into us from too much operation on the local repeater.

That fact that you have worked stations all over with just 5 Watts or less
and an HT PROVES that your point is invalid.  You were able to capture the
bird and make a QSO.  If your point was valid, you would never had made
those QSOs as all the guys running high power would have blocked you out.

The fact is that if people LISTEN more and don't just call and call and
call, the birds will go smoother.  It really matters not what power who is
running.  If the bird hears you, it hears you.  Your skill in operating is
what sets you apart from the rest.  If everyone listened (including the high
power folks), the QRP people would get into the bird just fine.  So listen,
listen, listen, listen and listen again.

The good Lord gave you two ears and one mouth.  Use them in that proportion!



Jon Ogden
NA9D (ex: KE9NA)



"A life lived in fear is a life half lived."

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