File:Yagi.svg

Self-created diagram of a typical single-director Yagi-Uda antenna.

Created using the following Asymptote script, touched up in Inkscape: import graph;

int lambda=200, arrowspace=5, circlesize=4; pair reflecto=(10,((lambda/2)-(0.55*lambda))/2); pair driveno=(10+lambda/10,0); pair directo=(10+2*lambda/10,((lambda/2) - (0.45*lambda))/2);

pair drivenc=driveno+(0,lambda/4);


unitsize(1mm); draw(reflecto-(arrowspace,0)--reflecto+(-arrowspace,0.55*lambda),Arrows,L=scale(1.5)*"$0.55\lambda$",align=LeftSide); draw(driveno+(arrowspace,0)--driveno+(arrowspace,lambda/2),Arrows,L=scale(2)*"$\frac{\lambda}{2}$",align=RightSide); draw(directo+(arrowspace,0)--directo+(arrowspace,0.45*lambda),Arrows,L=scale(1.5)*"$0.45\lambda$",align=RightSide);

draw(driveno+(0,lambda/2+arrowspace)--driveno+(-lambda/10,lambda/2+arrowspace),Arrows,L=scale(2)*"$\frac{\lambda}{10}$",align=N); draw(driveno+(0,lambda/2+arrowspace)--driveno+(lambda/10,lambda/2+arrowspace),Arrows,L=scale(2)*"$\frac{\lambda}{10}$",align=N);


currentpen=linewidth(2)+magenta+white; draw(reflecto--reflecto+(0,0.55*lambda)); draw(directo--directo+(0,0.45*lambda));

currentpen=linewidth(2)+rgb(0,255,0); draw(driveno--driveno+(0,lambda/2));

currentpen=linewidth(1)+rgb(0,0,255); filldraw(circle(drivenc,circlesize),white,blue);

draw(shift(drivenc)*scale(0.8)*graph(sin,-pi,pi));

currentpen=linewidth(2)+orange; draw(drivenc+(2.5*lambda/10,0)--drivenc+((3*lambda/10),0),EndArrow);

This work is ineligible for copyright and therefore in the public domain because it consists entirely of information that is common property and contains no original authorship.