[aprssig] Feeding impedance QUAD antenna

Ray Wells vk2tv at exemail.com.au
Sat Jan 27 02:06:46 EST 2007


Andrew Rich wrote:

> Gudday
>  
> I am now up to the stage of feeding my 8 element quad for 145.825 MHz.
>  
> I have been doing some reading and I see that most talk of a 100 ohm 
> feed point.
>  
> The most popular seems to be a 1/4 wave section of 75 ohm cable in 
> series ?
>  
> Does this look right:-
>  
> Freq = 145.825 MHz
> 1/4 wave in coax = (200 / 145.825 MHz) /4  = 34.28 cm's of 75 ohm cable.
>  

Depends on the velocity factor of the Q section.

Ray vk2tv





More information about the aprssig mailing list