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Pete W2PM wrote : Im starting to compare a half size pennant now pointing to VK
from here with a Short bog. Something less than 150 ft. long. So far casual
observations areshowing significantly greater output from the bog but I need to
do more careful and controlled observations. The half pennant is too low in
output for the veryweak signals I am experiencing here. I've used the half
quite well to Europefor 160 however.
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This summer I installed 3 small point fed pennants (51.6% the size of full size
pennants) pointing 40 deg (Europe), 160 deg(Caribbean), and 300 deg
(Pacific\Asia) from the Indianapolis area, and I am using a W1FB preamp which
has more than enough gain to match S meter readings equivalent with my 68 foot
base loaded vertical on 160 meters (looks like my preamp still has
approximately 12 db of additional gain if needed). If interested you can hear
some of my recordings using my pennants on YouTube (just do a search for WD8DSB
which will bring up a listing of numerous recordings I have done). I also have
a simple website that documents my 3 point fed pennant project and the URL is
http://sites.google.com/site/pennantflagantennas/
I did some slight modifications to the W1FB preamp to prevent failures of the
amplifier IC when the amplifier was exposed to high signal levels from my TX
antenna when I was running 100 watts, and I documented this modification last
year on the topband reflector. The modification has worked just great, and my
TX antenna is only 40 feet from the feedpoint of my point fed pennants (running
100 watts I have not found the need to use any additional front end protection
devices besides the modifications I incorporated in my preamp). At some point
in time I would like to try a couple of very low noise preamps in series (two
in series due to the gain requirement) to see if a lower noise factor preamp
offers any advantage on 160 meters compared with the W1FB preamp (I previously
tried a KD9SV preamp vs the W1FB preamp using a small loop on 160 meters and
did not notice any improvement in S\N ratio).
Next season I will probably try phased half size pennants in an attempt to
approach the performance of a full size beverage (similar RDF values) from a
small suburban lot, but will also probably test out a BOG.
73's
Don Kirk (wd8dsb)
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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