3elyagimaxfb.nec

zip contains tool for Antenna Modelling with examples

CM Max Front-to-Back 3-Element Yagi Design, Enter Design Frequency and Element
CM Diameter and set/select current units of measure. Model will calculate
CM element lengths and spacing for maximum 180-degree front-to-back ratio.
CM Element diameter range: 3E-4 to 1E-2 WL
CM
CE By L. B. Cebik, W4RNL (http://www.cebik.com)

SY Fr=28.75 		' Enter Desired Frequency in MHz.
SY WD=33			' Enter Wire Diameter in mm/inch/WL.
SY Hgh=0			' Average Quad height above ground mtr (ft)

SY Inp=mm			' Enable this line for diameter in mm
'SY Inp=in			' Enable this line for diameter in inch
'SY Inp=299.7925/Fr	' Enable this line for diameter in wavelengths

SY D=(WD*Inp*FR)/299.7925	' Get wire diameter in wavelengths
SY D1=LOG(D)/log(10), D4=D1^4, D3=D1^3,D2=D1^2

SY Rel=-0.006330181818*D4-0.07473777778*D3-0.3305042424*D2-0.6517507937*D1-0.235223671
SY Drl=0.007257212121*D4+0.08419555556*D3+0.3603660606*D2+0.6680392063*D1+0.6865069654
SY Dil=0.00693430303*D4+0.07956444444*D3+0.3341948485*D2+0.5971698413*D1+0.595447158
SY Red=0.1003704242*D4+1.17784*D3+5.144348788*D2+9.942252381*D1+7.343132812
sy Did=0.06885818182*D4+0.8022222222*D3+3.476657576*D2+6.668892063*D1+5.092856861 - Red

SY Scal=1				' Use this line if output dimensions in meters.
'SY Scal=ft				' Use this line if output dimensions in feet.
SY WL=299.7925/(Scal*Fr) 	' Wavelength in Meters/Feet

SY Refl=Rel*WL		' Reflector half length.
SY Dril=Drl*WL		' Driver half length.
SY Dirl=Dil*WL		' Director half side.
SY Refd=Red*WL		' Reflector distance
SY Dird=Did*WL		' Director distance
SY Wr=D/2 * WL		' Wire radius.

GW	1	11	0	-Dril	Hgh	0	Dril	Hgh	Wr	'Driver
GW	2	11	-Refd	-Refl	Hgh	-Refd	Refl	Hgh	Wr	'Reflector
GW	2	11	Dird	-Dirl	Hgh	Dird	Dirl	Hgh	Wr	'Director

GS	0	0	Scal
GE
EK

LD	5	0	0	0	58000000		' Copper wire
EX	0	1	6	0	1	0	
'GN	2	0	0	0	13	0.005		' Use this line if ground used

FR	0	1	0	0	Fr	0
EN