Command | Description |
---|---|
CM | Full line comment |
CE | End of initial comment block |
SY | Variables definition (4nec2 only) |
GW | Wire Specification |
GE | End of Geometry Input |
GN | Ground parameters |
GS | Scale Structure Dimensions (if you really want to use feet instead of meters add a "GS 0.3048" to your file) |
EX | Excitation - usually via one of the defined wire segments |
FR | Frequency - frequency for calculations and plots |
EN | End of input |
' | Adds comments to the end of a line. |
Command | Comment |
---|---|
CM | Classic Inverted V for 40m, taller centre pole shorter outer poles |
CM | Example by Roger Walker, GW6HRU |
CE |
Command | Variable | Value/Calc | Comment |
---|---|---|---|
CM These are the input values | |||
SY | freq = | 7.100 | 'Frequency (in MHz) - Usually easier to work with than wavelength |
SY | midheight = | 8.0 | 'Midpoint height (in meters) |
SY | endheight = | 5.0 | 'End height (in meters) |
SY | feedwidth = | 0.08 | 'Feed point width (in meters) |
SY | radius = | 0.0005 | 'Wire radius (in meters) |
SY | factor = | 0.98 | 'Velocity and ground proximity factor, start with 98% |
CM These are the calculated values | |||
SY | wavelen = | 299.792458/freq | 'Wavelength of freq (in freespace) |
SY | wirelen = | factor*wavelen/4 | 'Length of each wire (a quarter wave, with velocity/ground factor) |
SY | halfwidth = | sqr(wirelen^2 - (midheight-endheight)^2) | 'Pythagoras: Diagonal2 = Width2 + Height2 So: Width=√(Diagonal2 - Height2) |
Command | Tag | Num segs | Start | End | Radius | Comment | ||||
---|---|---|---|---|---|---|---|---|---|---|
GW | 99 | 1 | -feedwidth/2 | 0.0 | midheight | feedwidth/2 | 0.0 | midheight | radius | 'Feed point |
GW | 10 | 45 | -feedwidth/2 | 0.0 | midheight | -halfwidth | 0.0 | endheight | radius | 'Left diagonal wire |
GW | 11 | 45 | feedwidth/2 | 0.0 | midheight | halfwidth | 0.0 | endheight | radius | 'Right diagonal wire |
Command | Parameters | Comment |
---|---|---|
GE | 1 | 'End of geomentry, 1=Use Real Ground |
GN | 2 0 0 0 4 0.003 | 'Ground parameters, 2=Moderate, 4=dielectric constant, 0.003=Conductivity |
EX | 0 99 1 0 1 0 0 | 'Tag=99, segment=1, Load 0=Voltage source |
FR | 0 0 0 0 7.100 0 | 'Default frequency for modelling=7.100 |
EN |