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Re: uplink



Jerry,
FM is different than AM, It has capture and the higher the modulation the
lower the power per unit of bandwidth. The 'all knobs to the right
mentality' operators using processors are shooting themselves in the foot.
Reducing modulation to 3 or 4 KHz deviation and increasing "PL" CTCSS tone
to 1.5 KHz of deviation will give the operator the bast chance of reaching
the satellite. Power does not change the audio level of FM after reaching
full quieting. Additionally Doppler shift moves your operating frequency. If
the receiver has a 20 KHz bandwidth and your signal is 16 KHZ wide, 2 KHz of
Doppler will move the edge of your signal  to the end of the receiver
passband. This starts to distort your signal and reduce the signal into the
satellite.

Note: The transmitted bandwidth on FM is 2 X deviation + 2 X the highest
modulation frequency. I.E. 5 KHz Deviation and 3 KHz top audio limit = 16
KHz, or an emission designator of 16F3. A reduction to 3 KHz and you are
12F3 and can now tolerate +/-4 KHz of Doppler shift.

Art, KC6UQH
----- Original Message -----
From: "Jerry" <jerco@pi.be>
To: <amsat-bb@AMSAT.Org>
Sent: Saturday, July 31, 2004 3:03 AM
Subject: [amsat-bb] uplink


> Hello all
>
> The problem of not getting into the bird, I think ,is that some people are
> using too much pwr,instead of  using barefood trx.
> I have the same problem sometimes,and I know my setup works very well on
all
> the other birds.I can switch the 4 polar. and the pwr of the TM-251E was
> just enough to get in...
>
> Best 73's
> See yah on the bird(s)
>
> Jerry,ON4CJQ
> ----
> Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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----
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