"Reg Edwards" wrote in message
...
Frank,

So NEC4 cannot calculate input impedance of the radial system and we
have almost reached a dead end.

Would it be possible to insert a loading coil ( 2.48 uH ) at the
bottom of the antenna to tune out its input reactance ( which is what
my program does.)

Then repeat the efficiency calculation and tell me what you get.
----
Reg.

Reg, According to NEC 4.1 the input impedance is near 40 ohms
(39.9373 + j 0.394926 ohms) at resonance (8.07 MHz). With
100 W input the total radiated power computes to 31.8 W. I am
continuing with checking the program to be certain I have not made
an error, and also working on a NEC solution to the input impedance
of one radial. Note that the computation also includes copper loss,
which should be insignificant. I have also included a copy of my
code below.

Frank

CM Reg's test Vertical
CE
GW 1 36 0 0 9 0 0 0.05
GC 0 0 .9 0.00082 0.00082
GW 38 3 0 0 0.05 0 0 -0.025 0.00082
GW 2 40 0 0 -0.025 0 10 -0.025
GC 0 0 1.11 0.00082 0.00082
GM 1 35 0 0 10 0 0 0 2 1 2 40
GE -1
GN 2 0 0 0 16 0.0067
FR 0 1 0 0 8.07 0.01
EX 0 38 2 00 89.37696044 0
LD 5 1 1 36 5.8001E7.......

........................

.........................
LD 5 36 1 60 5.8001E7
RP 0 181 1 1000 -90 90 1.00000 1.00000
EN