[CQ-Contest] 4 Square/ Raised Radial Questions

[Tom Rauch]

> 1) Since my 4 square is "cut" for 3.65 and the radials 
> need
> to work on 3.5 as well as 3.8mhz, do I cut the radials
> for 3.5 mhz with the thought that slightly too long (for 
> 3.8 mhz)
> is ok?

It makes very little difference. What I did when I made 
elevated radial measurements is I tuned the radials to 
resonance by connecting them as dipoles. Then after they 
were tuned, I connected themm as radials. If you are stuck 
using elevated radials I'd tune them for the middle of the 
band.

> 2) What is the correct formula for use with raised 
> radials:
>
> Is it 246/f or 234/f?

Neither. The dirt is too close  unless the radials are 50 or 
100 feet high. If they are way up in the air you can 
probably use 234/f.

.

> 3) The radials are all pvc coated.  In theory this adds
> 2-5% length to the radial or lowers the resonant freq.
> by 2-5%.  Any actual experience to confirm this?

That happens, but the earth is a bigger influence.


> 4) If I use 3 - 4 radials on each of the four "legs",
> does it matter how I orient the radials?

Not really. Generally the best policy is to have them occupy 
maximum spatial area.

> 5) I am using Seven 31 material ferrites at the feedpoint
> of each "leg".  The ferrites raise the resonant freq.
> of the 1/4 wavelength coax about 20 khz as measured with
> the MFJ 269.

Why would they do that???? How are you measuring it? The 
beads have no effect on the electrical length of the cable. 
None.

They only affect the common mode, never the differential 
mode.

73 Tom