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Old February 6th 06, 09:29 PM posted to rec.radio.amateur.antenna
Bob Bob
 
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Default Passive Repeater

Hi again Bryan

A passive repeater is very simple.

You simply take two antennas and join them with feeder, then point one
antenna at one end of the link and the other at the other end of the
link. You may need to separate them some so they dont interfere with
each others capture pattern.

There will be a link budget that defines how much system gain (and thus
antenna gain) you need. You could conceivably get away with using the
standard AP antenna at that one end. As I said previously the software I
use for this is broken and I am not in a position to redo it by hand
just at the moment. There is a simple formula for determining path loss
over a line of sight path. You just do that twice with the received
strength at the repeater being the source power for the next link (minus
about 3dB)

What are the distances from each site to the passive rptr location? If
one does the calclulation then outoput power and receiver sensitivity is
also needed.

Cheers Bob

Bryan Martin wrote:
Ok, my first test failed so far. Example of what I am doing is here
http://home.triad.rr.com/tempdir/images/layout.jpg. My next thing I am
thinking about trying is to place some kind of somewhat small (no billboard)
passive repeater at the end of the powerline attached to a utility pole
where it meets the field. No power this far out and trenching is not an
option. I can google and find hords of info about people using passive
repeaters to bend the signal but I cannot find an actual passive repeater or
how to build one. Also when dealing with this type of repeater would it
force me to have directional antenna's at both ends where currently I have
only the one directional parabolic grid at the top of the powerline and just
a standard AP inside the building. Anyone think of anything else that may
work. going over the forest is also not an option. I own the land where
the grid antenna is located but I dont own the land where the building is
located as I just have permission to place a AP at that site. I am trying
to make the impact as minimal as possible at that site.

Bryan