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October 30th 03, 12:08 AM

On 29 Oct 2003 20:28:07 GMT, (ARDUJENSKI) wrote:

Richard and Reg
Thanks for the feedback. Let me ask a question that goes hand in hand with the
initial querry. When you set up the vertical and its parasitic how do you tune
them for either max gain or max F/B ratio? You can set the height differences
by plus or minus 5 percent and space between 0.15 and 0.20 wl but this will get
you in the ballpark. I had heard to install a variable cap at the base to fine
tune the arrangement but how do you tune it? With a second person and a field
strength meter and either tune for max fwd signal or min signal off the back?

Hi Alan,

I would suggest you return to your modeling with EZNEC for a first
pass approximation. As for the final tune, I cannot see how you can
escape the test of the model without some field work. Max Gain and
best F/B are not always achieved with the same solution; so you may
wish to commit to which is more important. You may also want to
investigate how to reverse the pattern (switchable driven element).

73's
Richard Clark, KB7QHC