In a message dated 98-05-22 17:20:11 EDT, you write:
<< How my much variance in SWR and bandwidth
will there be when the antenna is at 70 feet versus 25 feet?
I don't know. What have you observed? Hard to predict due to other
structures in proximity that may influence it.
>We have had
the antenna at 20 to 25 feet during the tuning process.
From what I have been told there will be a difference on 40 meters. >>
Most HF antennas will resonate lower in frequency when close to the
ground due to the added capacity of earth. So when you get them in the air,
the resonance usually goes up in frequency. The 40 will probably be more
susceptible to this than the 10-20 parts.
Did you tune each 40M element independently? It will work the best when
you do this. Otherwise your performance may be below par.
Cheers, Steve K7LXC
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