free operating software

PolarPlot - Freeware antenna software that lets you see what the polar diagram of your rotatable beam actually looks like where it is operating. With PolarPlot you can measure the polar diagram of the antenna and check for abnormalities - compare plots taken before and after changes to the design or location - check the -3dB beamwidth - look at the front to back ratio - see the size and position of the sidelobes.

Antenna Model - Commercial software for the analysis of wire antennas. runs under most Microsoft 32-bit Windows operating systems—Windows 98/ME/NT4/2000/XP Analyze most wire antennas in free space, over perfect ground, or over real-world grounds with the conductivity and dielectric constant you specify. You describe the antenna to the program in easy-to-use spreadsheet-style input window

Microwave Antenna Design Calculator - Available to run on all major operating systems, this free calculator provides quick estimation of antenna size required for a given gain and frequency.

CLX Packet Cluster - CLX is a clone of AK1A PacketCluster that runs under the Linux operating system. Freeware packet cluster server software

Predict - Satellite Tracking/Orbital Prediction Program an open-source, multi-user satellite tracking and orbital prediction program written under the Linux operating system by John A. Magliacane, KD2BD. PREDICT is free software