What does MHz, GHz and mW mean on the transmitters?
The abbreviation Hz is a unit used to measure frequency. In other other words, 1 hertz = 1 cycle per second, 1MHz megahertz is 1 million cycles per second, 1GHz Gigahertz is 1 billion cycles per second.
The abbreviation W is a unit of measurement used to measure the amount of output power of a transmitter, and mW (milliwatt) is 1/1000 of a watt, 1000mW=1 Watt, 500mW=0.5 Watt