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Re: Uplink Power



Eddy,

     At the risk of being politically incorrect.  It takes quite a bit more
U band uplink than originally thought.  It takes more than AO-13 did, and
more than AO-10 does when it is working.  I have more punch than I did on
AO-13 and my uplink is marginal at best.  I had a solid uplink on AO-13.  We
have to remember the bird is out further than intended.  It would stand to
reason the L band uplink numbers need to be revised upward as well.

      I am now prepared for the onslaught of emails telling me I just don't
hear well enough (that is always the response to a post like the one above).

1. If I hear myself (yes I know I am very weak, but readable).

2.  I hear the other guys just fine.

3.  The other guys can barely hear me or not hear me at all.

4.  We are all 10 dB or more below the beacon.

It would stand to reason that I need more uplink!  I am working on it.

73,
Joe
ka0yos@amsat.org

----- Original Message -----
From: "Eddy Jespers" <ejespers@wanadoo.be>
To: "AMSAT-DL Journal" <amsat-dl-journal@AMSAT.Org>; <amsat-bb@AMSAT.Org>
Sent: Thursday, July 19, 2001 4:45 PM
Subject: [amsat-bb] Uplink Power


> I did some testing on U-S and L-S.
>
> On orbit 330 i made a couple of contacts on
> U-S and L-S
>
> On Uhf i have an 14 dBic antenna, and 75 watt
> of power, around 33 dBW. This gives me a good
> downlink signal. ( no leila) .
>
> On L band i have around16 dBic antenna gain and 10
> watt. (around 26 dBW )
>
> Downlink signals on U where  OK, but on L band, the signal
> is marginal... . If i compare with AO40v2.0 i should trigger the max
> transponder floor with this EIRP
>
> OK we have still a squint angle, but this was relatively
> low this evening, lowesti've seen is about 4 degrees.
>
> Or, i have a receive/transmit problem, or the satellite
> EIRP as given is not correct.
>
> I will calibrate the G/T of the antennas in the next days,
>
> I was working stations running 30 turn helix and 60
> watt of power on the L band uplink with a good
> downlink signal ( this is 35 dBw ! ) giving a downlink
> of around -10 MB )
>
> Any other receive reports ?
>
> Best 73's Eddy ON7UN
>
>
> ----
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