Thought I would solicit some advise from some experts.
New 3 element 40M yagi at 70 feet - I get two dips - something like 6850 and
about 7200 when looking at the impedance with an MFJ-259B. I DO NOT get that
double dip when looking at the top antenna which is at 150 feet. The top one
is about 42 ohms at 7000, about 50 ohms at 7075 and probably about 75 ohms at
7200.
There is definitely something wrong as I have NEVER yet seen a European which
is as strong on both antennas fed in phase as the upper one by itself. The
bottom one by itself is down by something like 5-10 DB on the long haul stuff
(guessing, comparing the two antennas) which is okay. Have not put up a dipole
to see if it is any better than that.
The guy wires shouldn't be a problem although they are not eliminated as being
the cause just yet. If anyone has experienced this kind of matching problem or
interaction problem that caused the antenna to have two distinct places in the
band where the impedance approached 50 ohms or has any suggestions as to what
list of things to do to solve this problem, I would appreciate hearing from
you. I know what I am going to try first, second, and third but not sure what
else to put in there before I get to about 10 when the antenna comes down for
evaluation.
Stan, K5GO
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