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The Legal Power Output for Two Meters

Federal Communications Commission regulations state that ham radio operators in the United States may legally transmit only the minimum power necessary to carry out the desired communication. No ham station may transmit more than 1500 watts unless otherwise restricted. Two meters represents the most popular frequency range used by ham radio operators.

Two-Meter Band
- Two meters, or about six and a half feet, represents the wavelength of the amateur radio frequency band that operates from 144.00 MHz to 147.99 MHz. A basic antenna for the two-meter band is one-fourth of a wavelength or roughly 1.65 feet. The band's popularity stems from the ability to use a relatively short antenna for high gain and better performance. You can use the band in a car or RV on the highways, on a boat or on at a base station in your home.
Power Options
- Although the FCC regulations may seem difficult to define, most ham operators transmit in the two-meter band at up to 50 watts, which is enough power to reach up to 100 miles. The radio waves travel in a straight line-of-sight pattern that can't pass through buildings, hills or mountains. In many areas, amateur radio clubs build repeater stations with an antenna on a tower to carry the signals farther. In some areas, the repeaters are installed on buildings or nearby hills or mountains to reach longer distances.
Moon Bounce
- Some ham operators use a directional antenna pointed at the moon to bounce a signal back to earth. This operation requires 1,000 watts of power to be effective. To increase the power to 1,500 increases the effectiveness of moon bounce but requires more sophisticated technology and costs considerably more. Ham operators usually build the equipment necessary and arrange specific events to talk with other enthusiasts around the globe.
Power Measurement
- The FCC requirement states the legal maximum power as 1,500 watts PEP, which means peak envelope power. The power must be measured at the transmitter output with the signal fully modulated with voice. Most enthusiasts build transmitters with built-in gauges or meters to measure the power. Other methods include more expensive test equipment that includes power meters, oscilloscopes and spectrum analyzers. Amateur radio operators must file for a license with the FCC and pass a test that proves they know the laws and methods of properly measuring power before going on the air.

Ham Radio