SWR readings between 2.0 and 3.0 indicate a poor antenna mounting location on your vehicle. Although SWR of 3.0 across all channels usually indicates an installation mistake or faulty equipment, it can also occur due to a poor mounting location.
Mounting situations or locations that can lead to high SWR include:
- If the antenna is surrounded by metal
- If the antenna is sandwiched between two surfaces (i.e., between a pickup bed and the cab)
- If the majority of the antenna is blocked or boxed in by some part of the vehicle
- If the entire antenna is below the roof of the vehicle
In situations like these, the mounting location can make it hard or impossible to tune your antenna. If you've followed all the previously discussed troubleshooting advice to no avail, and your mounting location is similar to one mentioned above, we'd recommend moving your antenna to a different location on the vehicle.
Before completing a second permanent installation, we'd suggest doing a "dummy tune" -- tuning your antenna while someone else holds it in place in the new location. This way, if it still doesn't tune up properly, you haven't wasted time and effort on a worthless installation. When doing a "dummy tune," make sure that the mounting surface receives a good ground or you won't be able to tune properly.
For information on picking a suitable mounting location, please see our article, Choosing the Best CB Antenna.