HamCalc is a collection of calculators, for radio amateurs, presented as a series of 'Tabbed' pages.
* Antenna ERP calculations.
* Attenuator calculations.
* Audio filter design.
GEOPoint is an easy to use satellite antenna pointing calculator, for geostationary communications satellites. It calculates the azimuth and elevation pointing angles from a given location on the earth towards a specified geostationary satellite. The program also calculates polarisation tilt angles, estimates dates and times of annual sun-outage events, calculates antenna G/T, eirp and frequency stability, and estimates path-loss and rain-attenuation based on ITU-R climate models .