Objectives of CB Antenna Tuning
- To enjoy optimum CB performance (proper transmit & receive).
- Preventing your CB Radio from damage.
- Lowering your SWR reading. (Acceptable SWR = 1.8 or less).
OK, everything is now connected and ready to transmit & receive. Wait… there is something we’ve left behind. And that is CB Antenna Tuning Process. Remember, it is a very prominent step. Operating transceiver without tuning process increases the chance of your radio to get damaged.
What is the CB Antenna Tuning? It the process in which we adjust antenna’s length to achieve optimum performance. Or we can say actual terminology behind the tuning is also based on increasing or decreasing the antenna’s length.
Understanding SWR: The perfect way to understand SWR is by example. Radio is connected to the antenna by the mean of a cable (COAX). When you talk the radio develops frequency that travels with the help of the COAX cable. Voltage is traveled through a wire connected to the antenna & propagates back down the line in the reverse direction to the radio. SWR is the measure of what is occurring to the forward & reverse voltage waveforms.
Equipment Required: First of all, install your radio & antenna properly. Now you’ll need an SWR meter and short length coaxial cable known as jumper lead. You can buy both from any nearer CB shop. Let’s start the process.
CB Antenna Tuning Process
- Find an open space
Take your car to an open ground or a field where there is plenty of open space around and no trees or tall buildings can be seen nearby. Make everyone sit inside the car and keep the doors and windows of the vehicle closed for saving the SWR readings from fluctuations.
- Connect the SWR Meter
Now you need to put the SWR meter in place. Connect it in a way that the SWR meter is in the middle of the radio and the CB antenna. Connect the antenna to the SWR meter through the point named ‘ANT’ and connect the CB radio to the meter through the ‘XMIT’ connector. Note: Adjust the microphone in a way that its distance from the SWR meter remains unchanged throughout the measurement.
- Time to take SWR readings
Now start the tuning process for channel 1 by adjusting the SWR meter to ‘FWD’, keying the mike and starting with channel one of the band. Then turn the adjusting knob of the meter to set the needle on the scale. The switch of the SWR meter would be fixed to ‘REF’ while keeping all the other settings the same as before. At this point, note the reading on the meter and release the mike’s key. Repeat all the steps for channel 40 and take the reading.
If SWR reading from channel 40 is greater than that recorded on channel 1, then the antenna is longer than required.
If your antenna is too long, then its length has to be shortened through the tunable tip or by trimming it to the required length. Which method suits your CB antenna can be checked from your instructions manual but you have to take new readings for whatever length you achieve for your CB antenna.
If SWR reading from channel 1 is higher than that recorded on channel 40, then the antenna is shorter than required.
If your antenna is too short, then you need to bring it to the required length. You can do it by adding spring between the whip and the mount, or you can try a different length of the shaft as provided with the SR-2K antennas from Stryker.
After achieving the desired results, unplug the jumper leads & SWR meter from your radio. Connect your radio with you CB antenna again with the help of a coaxial cable. Congrats! You’ve tuned your CB antenna. Now you can enjoy your journey…
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