> JE>Conventional thinking, maybe But, traps have historically been
sed
> JE>-and, they're a compromise.
> JE>
> JE> > Interesting idea, but I've never tried it. The only thing I've
> JE> > done is 80 and 40 meter dipoles fed with a single coax.
> JE>
> Very interesting theory. As I understand it, it's the same as
> having having
> both an 80 and 40 meter dipole on the same coax, except the V is
> about 30 ft
> down each leg of the 80 meter dipole, instead of at the center.
Don't know what 'V' you're talking about... stretch it out as a normal
"flat-top" dipole or string it as an inverted vee - either way, at 75m (for
example 3.900MHz) each leg is 60' (468/3.9 = 120 = 1/2 wavelength - each leg
of a dipole is 1/4 wavelength, so 120'/2 = 60').
Measure out the quarter wave length at the desired 40m frequency (for example
7.2MHz - 468/7.2 = 65 = 1/2 wavelength - 65/2 = 32.5 ft)
at the 40m 1/4 wavelength point, hang about a 4" peice of wire from
the existing dipole, on each side of the feed line.
> I'm still going to use separate 80 and 40 meter dipoles for my
> home station,
> because I'm also using the antennas to guy the 10 ft mast I'll
> be using.
I can relate to that
> But, I'll keep it in mind for a field antenna. It would
> definately make for less tangled wires.
I will probably be doing some like this, this comming week myself.
Will inform of my results.
73 = Best Regards
-Jeff KA5THB
ka5thb@bigfoot.com
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