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BEST satellite radio?

Message text written by Franklin Antonio
>A related question:  I don't know how much power I'm going to need to 
deliver to the antenna on 1.2 GHz for P3D.   Thoughts and/or references to 
articles appreciated.  There is a page of info on ground station 
considerations in the P3D section of the AMSAT web <

        The link analysis by Frank Sperber of AMSAT-DL suggests that 10
watts to a 12 turn helix should be adequate for SSB. In that light, I put
together a project for the 1998 (and later) ARRL Handbook on "An integrated
L-band satellite antenna and amplifier" with a 15-turn helix
counterbalanced by an antenna-mounted 15 watt 1269 amplifier made from an
M57762 brick. Easy to build and no tuning required. Mounting the amp right
at the antenna not only eliminates line loss to get full power to the
antenna  but also serves to counterbalance the weight of the helix. It is
designed for use with a 10watt transmitter in the shack, where you use the
length of feedline between the transmitter and the M57762 amp to attenuate
the 10watts to the 1watt level required by the brick. Templates for the amp
PCB are available.

Ed Krome K9EK (ex-KA9LNV)

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