Install xnecview by entering the following commands in the terminal:
sudo apt update sudo apt install xnecview
Description:
NEC structure and gain pattern viewer
xnecview allows a representation of a NEC (Numerical Electromagnetics Code) structure, such as an antenna which is to be modelled to be displayed on the screen. After an NEC run the gain pattern in various formats can also be superimposed. This can be rotated and translated for viewing from different angles. Plots of SWR and gain as a function of frequency can also be produced. In addition to on screen display, Postscript or PNG output can also be produced.
Homepage: https://www.cs.utwente.nl/~ptdeboer/ham/xnecview/
Version: 1.36-1
Section: universe/hamradio