[TowerTalk] Radial Length

[Frank Latos]

>At 08:53 AM 6/20/2005, Don Josephs wrote:
>  
>
>> Folks  de  K5DEJ
>>
>>Is there a formula for determining the radial length, i.e. other than 468/f
>>MHz ???   I am trying to get a High Sierra 1800 Pro to resonate on my Motor
>>Home and have not been successful, as of this writing.
>>    
>>
I have essentially the same antenna.  My installation (on a full-size 
pickup truck) works well on 80, 40, and 30 meters with a
4:1 "un-un" transformer for impedance matching.  I used the "5-ratio 
un-un" design described in chapter 15 of Sevick's book
"Understanding, Building, and Using Baluns and Ununs". 

The 12.5 ohm tap (4:1) provides a good match on 80 - 30, and the 35 ohm 
tap works well on 20 - 10.

Frank AC8P