Check your SWR: Write down the SWR reading on channels 1, 20, and 40 based on the instructions above.
Adjust your antenna: If your SWR reading is higher on channel 40 than it is on channel 1, lower something on your antenna. If channel 1 is higher than 40, raise something on your antenna. If channels 1 and 40 are (about) the same, and your lowest reading is on channel 20, then you are done.
Verify your SWR: In most cases you're looking for the same SWR reading on channels 1 and 40, with your lowest on 20. As long as your SWR is less than a 2 on all 40 channels, you're good.
What about dual antennas?: The process is the same, just adjust both antennas at the same amount.
Plumber G256 Sent us this link on SWR
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