AMSTAT Amatuer Radio in Space (external link) Antenna Calculator Make the Right Sized Antenna (external link) APRS See APRS traffic in your area (external link) EchoLink EchoLink® software allows licensed Amateur Radio stations to communicate with one another over the Internet, using streaming-audio technology. The program allows worldwide connections to be made between stations, or from computer to station, greatly enhancing Amateur Radio's communications capabilities. There are more than 200,000 validated users worldwide — in 151 of the world's 193 nations — with about 6,000 online at any given time. (external link) FCC Vanity License Search (external link) SDR Radio Software (external link) SOTA (Summits On The Air) Provides SOTA (Summits On The Air) maps of activators and chasers. (external link) WebSDR WebSDR is a Software-Defined Radio receiver connected to the internet, allowing many listeners to listen and tune it simultaneously. SDR technology makes it possible that all listeners tune independently, and thus listen to different signals; this is in contrast to the many classical receivers that are already available via the internet. (external link)
