You only need to adjust the antenna length to properly tune it. Getting its length set properly maximizes how much power it sends out. A $15-20 SWR meter makes it a fairly simple process, set the length for the lowest SWR indication on the meter which means maximum power output. Checking & adjusting the SWR (standing wave ratio) also verifies if the antenna was installed correctly or not. Installed incorrectly an antenna will give a sky-high SWR indication on the SWR meter.
Handheld CBs & walkie-talkies are a PITA to use while driving. Better to buy & install a permanently mounted CB radio and antenna and they're relatively inexpensive. My long-term favorite CB is the the Uniden Pro-520XL which is only $43 at
https://www.amazon.com/dp/B00004VXNI/?tag=wranglerorg-20. Firestick CB antennas are cheap too.
I recommend a CB as the first radio for a Jeep since 99% of the 4x4 events and Jeepers use CBs as their main radio choice. Many organized 4x4 events require a CB. After that my recommendation for a second radio is a ham radio which requires a license to operate but fortunately the test for that license is easy with just a small amount of study.
This is my setup, though it's no longer as pretty as it was the day it was installed as shown here. The top radio is a Yaesu 2 meter ham radio, the bottom radio is the Uniden Pro-520xl CB radio.
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