The SWR meter or
VSWR (voltage standing wave ratio) meter measures the
standing wave ratio in a transmission line. This is an item of
radio equipment used to check the quality of the match between the
antenna and the
transmission line.The VSWR meter should be connected in the line as close as possible to the antenna. This is because all practical transmission lines have a certain amount of loss, causing the reflected power to be attenuated as it travels back along the cable, and producing an artificially low VSWR reading on the meter. If the meter is installed close to the antenna, then this problem is minimised.
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