The common slogan in topband is that you can't have too many antennas. My
new slogan at age 90 is that you can have too many (time for repairs,
maintenance, observing which rx antenna is best, etc) - my wife age 94 agrees.
This could be a long story. To start I listed the RDF of good or existing
rx antennas here. Then I had to review my goals - the main one is new
countries on 160, which might occur in a very few directions.
I do ragchew on other bands or help others who need MT. How to sort all
this out? One, don't start new complex projects. Next how to evaluate what
I have? Possible problems - rx antennas in tx antenna field, . Brute
force approach, do on the air comparisions with tx verticals shorted to ground
or open feedpoint (which is better) - is it a pattern distortion problem
or tx antenna reradiated noise problem (or does the test give the overall
answer - how big a problem is it?) Or how good are the feedlines for equal
phase delay in arrays? Should be easy to determine with some MFJ dip
measurements.
I could go on and on with a bunch of other factors or issues or variables.
One question is what is the RDF for a EWE broadside array (that I have in
the tx antenna field). See page 33 QST Feb 1995 by WA2WVL, figure 9,
which represents the array that I have, with 150' spacing. The beamwidth is
45
degrees which is pretty good. What though is the RDF? My computer skills
have faded out. This is the only RDF number that I don't have.
Thanks for listening.
73 Bob W7LR in MT _w7lr@aol.com_ (mailto:w7lr@aol.com)
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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