Antenna Tuning
Practical guide to SWR measurement and antenna tuning for mobile and base stations.
Description
The article details antenna tuning procedures, emphasizing SWR measurement and adjustment for both mobile and base station setups. It explains that SWR (Standing Wave Ratio) is the ratio of transmitted power to reflected power, with high SWR indicating poor impedance match and potential damage to a transceiver's final amplifier. Specific instructions are provided for CB antennas operating between 26-27 MHz, recommending initial SWR checks on channels 1, 20, and 40 to determine if the whip needs shortening or lengthening. Adjustments should be made in small increments, approximately 1/4 inch at a time, aiming for an SWR of 1.5:1 or better.
For Ham radio and other antennas, the same tuning principles apply, with a strong caution regarding RF energy exposure when operating at higher power levels. The resource suggests tuning base antennas at ground or roof level before final installation to simplify adjustments. It also advises rechecking SWR after final installation to confirm no changes occurred. The Alpha Rubicon resource highlights the importance of a good ground plane for mobile antennas and proper coax routing to avoid pinching or proximity to electrical wires.