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Old August 20th 03, 07:46 PM
Richard Clark
 
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On 19 Aug 2003 22:46:54 -0700, (VE8AE Andrew)
wrote:

I have an old Shakespear 32 ft antenna. Fed at side near bottom and a
large bottom plate. Want to know if I mount it up at the top of a mast
how long should I make radial wires for? Do I just calculate for
lowest freq and make them 1/8 wavelength? I am going to run it through
my tuner to get as many bands out of it as I can. Only about 40ft of
coax so it is not too long.
Or should I try and design my own trap vertical of some sort??
Thanks.
Andrew VE8AE


Hi Andrew,

I presume by "fed at side" that this is through some proprietary
matching - or is it simply insulated from ground?

Use a tuner and forget tuning the radials. You might be tempted to
build them to "formula" but given that they will no doubt be of the
drooping variety, then that is an entirely different game. As such,
add as many as you are comfortable with, as long as you can make them
without having to bury their tips (a good idea is that their lowest
point should be out of reach).

Be aware that as impressive as it may feel, the height may be a
detriment in the higher HF (too long and radiation will be skyward,
bound).

73's
Richard Clark, KB7QHC