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Re: Success !!!!!!!!!!!



>From: Margaret Leber <maggie@voicenet.com>
>guy lemke wrote:
>
>> Success what a great feeling !!!!!!! Set back after set back. I have
>> once again heard the data grams coming from AO-40...It has been awhile
>> since listening to the 2 meter beacon right after the launch...
>
>Congratulations, Guy; I know something about the feeling, even though I
>wussed out and bought a premodified Drake myself. Consensus sees to be
>building that for *good* performance with S2, with the bird configured
>as it was during the first experimental transponder operation period,
>most Drakes need some kind of preamp up front.
>
>Congratuations again, bravo zulu and 73 de Maggie K3XS

Congradualations Guy!

Maggie, When you said "most" Drakes need some kind of preamp, I'm sure you
did not intend to give the impression that a "bare" Drake is sufficient for
reception on AO-40.  With the exception of replacing the internal preamp
with a low NF device {if you are skillfull enough to replace the device,
you recognise the need, and do not need to be told}, normal use of the
Drake will require some kind of preamp <1 dBNF.  To imply otherwise is to
lead people to a situation where they become "alligators" on AO-40.

Unless you are using a "big" dish >5-foot diameter, only when squint angles
< 10 degrees, you just need to get that NF down.  The minimally modified
Drake {xtal change, IF change} is still a NF ~6 dB convertor.
DO NOT assume that a "bare" Drake or other MMDS convertor will hear
adequately without a preamp!
So I would just simply say "ALL" Drakes need a preamp {external or internal}! 

Ed
BTW this reminds me of a comment heard: "that it will be easier to hear the
S1 beacon/transponder".  But remember that the S1 antenna is a dish with a
narrower beamwidth, meaning squint angles will provide worse performance
than S2 [the better signal strength is only coming from the main beam which
is narrower].  Because of this, I still think one needs to build their 2.4G
receiving system to work with S2 at squints out to 20-25 degrees and
signals -10 dB down from the beacon.  To do otherwise is to fool yourself
into a situation that will frustrate you and those you attempt to work.  I
believe that those successfully hearing stations thru the S2 transponder
would agree.


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