[Boatanchors] The 100-foot Doublet - was Antenna Question

[Jim Wilhite]

Rob you know the answer, we are being picky down to the nat's ....

The trick is to get the most RF into the air possible. Do whatever it takes 
and SWR be darned. Design it, build it, install it, and then set about 
making it work.

People should read the books about current feed or voltage feed and work from there. The 
learning experience is what ham radio is all about.

I don't like that window line because the poly is not UV protected and, from 
installation, the distance between the conductors changes thereby changing 
the Z. But whatever floats your boat.

Jim
W5JO


----- Original Message ----- 

>I don't understand the interest in the 300 ohm and 450 ohm window line
> feed. Why is it preferable to 600 ohm or even higher Z line?
>
> The higher Z line is more stable under varying wx, handles more v. and
> current and usually has a lower vswr on it because its characteristic
> Z is often closer to the dipole feedpoint Z except on the 1/2 wave
> frequency. It also has a higher Vf and lower loss.
>