An swr meter (standing wave ratio) is a tool to measure the forward (out put power) of a transmitter, and the reflected power of a particular radio, antenna combination. Swr is the number used to describe the forward power lost due to incorrect tuning of the antenna to the intended out put frequency. This tunning is essential to the longevity of the transmitter and the quality of the signal. A low swr reading is good high is bad, generally tunning your swr to something under 1.5 is great but the lower the better. Be sure and calibrate your meter. This video shows a Radio Shack analog swr meter and use. = =
