How do you adjust swr

So what does tuning your antenna entail? The concept is simpler than the explanation of SWR. Adjusting the SWR is just matching the electrical length of your antenna to the desired frequency. This ensures that the impedances of the feedline and the antenna match perfectly, so that all available power is being radiated. To tune your antenna, you will need to use a SWR meter. This device is attached between your antenna and radio.

This device measures the amount of signal being reflected into your transmitter to help you measure the quality of your outgoing broad cast as well as any potential threat to your radio. Antenna tuning is the single most important thing you can do to ensure peak CB performance. If your antenna is too short , it is necessary to increase its physical length.

Most instances where the antenna length is too short are caused by a lack of ground plane. In modern antennas, there's usually a method for adding length built in to the antenna. Other options, such as adding a spring, are also legitimate. Dual antenna installations : If you're tuning dual antennas, you'll want to adjust both antennas the same amount each time.

As a starting point, it's best to put the tuning screw either all the way in or out, so each antenna is the same length. Re-measure SWR and continue to re-adjust as with a single antenna, making sure to make incremental changes that are as close as possible to both antennas. The meter measures Forward power to the antenna system and then compares it to the reverse or reflected power from the antenna system.

Instead of showing you power, the meter is calibrated to show the RATIO of coupling from radio to antenna system. If there is all forward power and no reflected power the antenna system has a one to one ratio with the transmitter. By checking the SWR at channels 1 and 40 on your CB, you will have a good idea if the antenna is too "long" or too "short" for the center of the desired band.

You will also be able to evaluate your system performance and troubleshoot problems. For instance a SWR too high over all over the band can be an indication of a bad part or junction, poor ground or poor location.

An SWR too low over the whole band for all 40 channels can indicate a low efficiency antenna or lossy component. Most people would prefer to be 1. A good quality antenna and proper installation location very important should easily result in an SWR of less than 1. Shorter Antennas tend to be more narrow banded and may have as high as a at the top and bottom of the band.

Here's one of the places you can evaluate your antenna. If you have an antenna that's say, three feet or less, and the SWR tunes great less than 1. In "Lossy" I mean that maybe the design or construction material is inferior and is wasting some of your energy as ground losses or increased heat dissipation. This causes both the forward and reflected power to be partially absorbed, thus showing a lower SWR on the meter.

If already connected, disconnect the coaxial cable from the radio. Connect the coax cable that normally connects to the back of the radio to the SWR meter connector marked "Antenna" or "Ant".