Topband: Inverted "L" vs." T"

[K4SAV]

W7RH wrote: Further with the T portion as top loading the feed point 
radiation resistance will be greater for a given vertical
height. This when coupled with an excellent ground system of 1/4 wave 
radials will make the antenna substantially more efficient than other 
types of loading. (Less Loss)

Why does NEC not confirm this statement?  An example: A T antenna and an 
L, both with the same ground loss, the same vertical section length 
(49.5 ft), and the same resonant frequency.  The T calculates as a 
feepoint impedance of 18.1 ohms at 1.81 MHz.  The L calculates as 20.2 
ohms at 1.81 MHz.  If you calculate the radiation resistance, the L will 
be 1.5 to 2 ohms higher.

Note: If you do these calculations with a Mininec ground, you will get 
in incorrect answer because there will be a low horizontal wire over a 
Mininec ground.  That always produces an impedance that is too low and a 
gain that is too high.  You have to use a real ground and simulate the 
radials, or do the calculations in free space.

Jerry, K4SAV