At 11:39 -0700 06/23/2001, [EMAIL PROTECTED] wrote:
>
>Anyone know off the top of their head the numerator in the formula for
>calculating the length of a dipole?
>I want to say 468?
At 15:03 -0700 06/23/2001, Dick Flanagan wrote:
>
>468 divided by the frequency in megahertz (468/f) will give you the
>length in feet of a QUARTER-wave. For a dipole you will need to double
>that figure or use 234/f for your original formula.
Oh, c'mon now...if that statement were correct, I could squeeze a full-size 160-meter
inverted vee on my 100x100-foot city lot. (234/1.8 = 130 feet - bingo! I'm on 160!)
The first statement is correct, 468 divided by the frequency in megahertz gives you
the approximate dimensions of a half-wave dipole, in feet (approximate means, the 468
figure comes from an assumption of the velocity factor of the wire, based on its
diameter, conductivity and such. The non-adjusted formula for a half-wave in free
space, in a vacuum, is 492 divided by the frequency in megahertz).
The formula for the approximate length of a quarter-wave vertical antenna is 234
divided by the frequency in megahertz.
Hope this helps.
--
J o h n B a s t i n K 8 A J S
[EMAIL PROTECTED] [EMAIL PROTECTED]
http://www.geocities.com/~tarquin
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