A common mistake when tuning a CB antenna is mixing up the two coax connections at the back on the SWR meter. If you don't make the correct connections, your SWR meter won't give you accurate readings and will likely show high SWR readings whatever you do!
All SWR meters should indicate which terminal should be connected to the antenna, and which should be connected to the radio. The labels are sometimes listed on the back of the meter, but are often printed on the front and can be easy to miss. The front label refers to the terminal directly behind it on the meter, as is visible in Image 1 and Image 2.
Image 1 - Terminal Labels
Image 2 - Back of the SWR Meter
TX
TX or Transmitter/Transceiver will be connected to the CB Radio you are tuning. Connect using a short coax cable from the TX connector to the SO-239 connector of the CB Radio you are tuning
ANT
This is where the you will attach the coax cable connected to the antenna.
The image below should show how they are interconnected.Be sure to take notice of the labels on the SWR meter and you'll save yourself a lot of frustration!
