At 09:58 AM 5/29/03 -0300, Scott Nichols wrote:
>I'm in the process of converting my station to SO2R and need some help...
>
>I have 2 MP's, one amp (for now), and one set of antennas (for now)
>consisting of a tri-bander and several dipoles, all fed through one coax
>switch in the shack...
>
>My biggest concern for the moment is antenna selection/switching and
>filtering, so as not to blow up one of the MP's front-ends...Been reading
>everything I can find on this, but unfortunately, I'm don't know enough
>about it to fully understand everything...
Just a couple of thoughts to add to the excellent info from others. The
MPs have an RX antenna loop out the back that can be used for inserting
some sort of receiver protector, which might be a good idea. If you look
back in the towertalk archive, you'll find a fairly extensive thread on
this in November 2001.
As one smart person observed during that discussion, a first step is to
learn just how much RF actually gets from one antenna to another (or from
one radio to another, not always the same thing). WE9V did these
measurements in his station, and wrote about it in an excellent article in
the May/June 2001 National Contest Journal, titled "Antenna Isolation in
the Real World."
For what it's worth, I opted for a minimal SO2R combination. With my
second radio on a trap vertical some 300 feet from my tower, I have had
relatively few problems (and no destructive ones) operating SO2R with no
filtering or other protection. It helps to keep the second radio on a band
lower than that used by the run radio, and stubs or bandpass filters would
certainly be helpful.
73, Pete N4ZR
The World HF Contest Station Database was updated 9 May 03.
Are you current? www.pvrc.org/wcsd/wcsdsearch.htm
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