[Antennas] radial lengths for 102 inch cb whip antenna

Sat Sep 4 10:19:44 EDT 2010

 The whip is NOT a 1/4 wave!
A 1/4 wave whip, (for CB), is 108". This whip in discussion, was length 
determined to INCLUDE the "SPRING" mount.
Therefore the whip needs to be extended, OR mounted on one of the 
"Springs" that these were intended for - OR a straight piece of steel or 
brass to make up for the length difference.
The best radial mounting as demonstrated by the "Starduster", was angled 
at 60 degrees, in reference to the vertical element. They are also 108" 
in length. Three do the job very well!
I was a "Chicken Bander" for several years before becoming an Amateur 
Operator.
Length for 10 mtrs would change ALL the lengths involved.
I use a 5/8 wave ground plane with a tuner to work 15 mtrs with an 
SB-102 right after getting licensed in 1980.
I made a cross mode contact with ZL2MM. He was working voice on SSB, 
and I was working CW in that Novice segment.
You would be amazed what will work! The theory and books ONLY provide 
"perfect" solutions. Dipoles and inverted Vees do NOT have to be 
straight line as always shown and their given illustrations. The end 
areas can be bent this way and other ways. You simply tune for resonance.
Then go for it and have a ball! Antennas are a "black" art! You can do 
much more with trial and error, using what space you have, and making 
the radiating element fit the existing space limitations.
Bob - N0DGN
On 8/30/2010 5:59 PM, Mike McCarthy, W1NR wrote:
> Since the wip is 1/4 wave, just make the radials the same length or 102
> inches.
>> Mike, W1NR
>> On 08/30/2010 05:50 PM, Barry Sherwood wrote:
>> 234/Fmhz= 234/27.185= 8.607 feet
>>>> On Mon, Aug 30, 2010 at 4:25 PM, Patrick J<pjm at nrvunwired.net> wrote:
>>>>>>> Group,
>>>>>> I am mounting a 102 inch cb whip on a building and would like to add
>>> some radials to improve performance. Could someone provide me the
>>> calculation(s) I could use to determine the optimal length for the radials?
>>>>>> Thanks,
>>>>>> Patrick
>>> KJ4TRT
>>>>>>