Topband: Wire antennas and antenna analyzers
w8ji at contesting.com
Fri Sep 29 13:49:12 EDT 2006
Dave, thanks for the great idea! I will use a T-connector
with a shorted BNC
plug when connecting the antenna.
And thanks to everyone who contributed to the subject!
73 de Björn /SM0MDG>>
Just a suggestion.
What I use to prevent damage is the MFJ filter designed for
use with the 259. We use 259's for some bench testing, and
if a control line is switched while the 259 is connected it
can change diode characteristics. After losing several
diodes I made it a rule to always use the filter. The filter
so far has totally stopped that problem.
Also, since all of these little analyzers are broadband
coupled to the antenna they are sensitive not only to
broadcast stations, they are also sensitive to dc and low
frequency ac offsets. The filter will help with those
I think the filter is a model 731, but I'm not sure. It is
out in the shop and having just been cut all up I'm in no
shape to walk out there to look.
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