vert20m.nec

zip contains tool for Antenna Modelling with examples

CM GP (50 Ohm feed)
CE
SY LEN=5.3 		' To optimise Z-in 
SY CAP=90pF 		' To optimise for resonance
GW 1 30 0.0 0.0  .05 0.0 0.0  LEN  .001
GW 2 1 0.0 0.0 0.0 0.0 0.0  .05  .001
GW 3 1 0.0 0.0  .05 0.0  .05 0.0  .001
GS 0 0 1.0
GE 1
EX 0 2  1  0  1.0 0.0
LD 0 3  1  1 0 0 CAP
GN 3 0 0 0 13  0.005 0.0 0.0
FR 0 1 0 0 14.05 1
RP 0  181  1  1000  90 0 -1  1 
EN