[time-nuts] GPS Filter

Chris Albertson albertson.chris at gmail.com
Fri Mar 4 20:20:42 UTC 2011


On Fri, Mar 4, 2011 at 10:31 AM, Bob Camp <lists at rtty.us> wrote:
now it's mainly military use. Obviously these guys are a bigger deal
for civilians than the military.
>
> So the question is - do the built in splitter filters have any real rejection 15 to 50 MHz off of center?

Most GPS antenna are active.  I'm a bit more worried about the preamps
built into the antenna.  A filter external to the antenna will not
protect the built-in preamp.

But there are all kinds of designs for home built GPS antenna.  A
helix antenna is not hard to make.  Timing GPSes at fixed sites can
use antenna that have a deep null aimed at the nearby transmitter
(which is also fixed)   People at fixed sites will have it easy.
Mobile  GPS users will not be able use antenna design.

-- 
=====
Chris Albertson
Redondo Beach, California



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