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How to Work an SWR Meter

In the realm of radio communications, which includes CB and ham radio as well as others, it is important for you to be able to measure the amount of radio-frequency (RF) energy being reflected back toward your radio transmitter during operation compared with the amount going out through the antenna and into the airwaves. This ratio is called the "Standing Wave Ratio̶1; (SWR) and if the reflected radiation is too great, your transmitter can be damaged. A reasonable ratio is 1.5 to 1, or 1.5:1. To see what your ratio is, you must know how to install and read an SWR meter.

Things You'll Need

SWR meter rated for the maximum output power of your transmitting device
Length of coaxial cable with appropriate RF connectors (such as PL-259)

Instructions

- 1
  Connect one end of a coaxial cable, with the appropriate RF connector, to your transmitter output connector, which is on the back of your radio. Connect the other end of the cable to the "RF Input" or "Transmitter In" jack on the back of your SWR meter. Screw both ends down tightly.
- 2
  Connect the coaxial cable, which goes out to your antenna, to the "ANT" or "RF Out" jack on the back of your SWR meter. Screw this connector down tightly.
- 3
  Set your SWR meter to measure either "Power" or "Reflected." The "Power" setting will show you the amount of RF power your transmitter is putting out, and the "Reflected" setting on an SWR meter shows you how much power is being reflected back toward your transmitter.
- 4
  Turn on the transmitter and press the transmit key briefly, five seconds or less if possible. If your meter is set to "Reflected," you will be seeing the reflected power. Observe the meter carefully while pressing the transmit key. If your meter's gauge reads 1.5:1 or less, this is generally a reasonable level. If the meter shows your reflected power to be greater than 1.5:1, you must make adjustments to your antenna to lower the SWR.

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