[Lowfer] Using a Whip above the Top-Hat QUESTION ??

[Andy - KU4XR]

Hello all:

I need to call upon your experiences again, this time on using
a vertical " whip " above the Top-Hat on a lowFER ant. I have
been searching the net for some info, but everything is pretty
vague, and mostly dealing with mobile ant. But I'm sure the same 
principle applies to Base Vertical ant. as well. I notice that 
there is not much mention of LOWfers using whips above their
Top-Hats, Is there no benefit to doing so ?? The summation of
what I have been able to understand on the subject is that there
is a relation to the length of the whip section, and the mast,
as well as the whip, and the Top-Hat length. The Mast/Whip is
primarily dealing with center loaded verticals with no Top-Hat.
" XR " is Base loaded ( Variometer ) with a 20' long Top-Hat.
The info I have read indicates that a whip above a Top-Hat
should not exceed 1/2 the Top-Hat length. Too long on the whip,
and it will begin to shorten the Effective Height of the ant.
by Top-Hat shielding of the whip section. There is no formula
that I have been able to find, to calculate this issue.

With the above thought; I can add a 10' wire to the top of my
vertical, and the total vertical length will be 40' long.
Will the extra 10' above the Top-Hat provide any benefit ??

Sidebar ::: The 10' at the top can easily be supported by a 
1/2" PVC pipe. I can't add it to the vertical section 
below the Top-Hat ( better I know ) because of where I have 
to place the ant.

What are your thoughts ?? Thanks for your replies, 73 for now.


Andy - KU4XR - EM75xr - Friendsville, TN.
LOWfer Beacon " XR " @ 184.322 KHz ( QRSS-60 )
Coordinates:  N:  35* 43' 54" - W:  84* 3' 16"
http://www.myspace.com/beaconxr