If your antenna is mounted down low on the vehicle, like on the bumper or behind a pickup truck's cab, the signal can bounce back to the antenna, causing a high SWR. To alleviate this, keep at least the top 12 inches of the antenna above the roof line, and position the antenna as high as possible on the vehicle.

What happens if your SWR is too high?

If the SWR on channel 40 is higher than that on channel 1, your antenna is too long. If the SWR on channel 1 is higher than that on channel 40, your antenna is too short.

What does a very high SWR reading mean?

What does a very high SWR reading mean? The transmitter is putting out more power than normal, showing that it is about to go bad. The antenna is the wrong length, or there may be an open or shorted connection somewhere in the feed line. There is a large amount of solar radiation, which means very poor radio conditions.

How do I lower the SWR on my ham antenna?

Start by moving your vehicle to an outside area, far from metal objects. Connect your SWR meter in line between your transceiver and antenna. Set your radio's transmit power level to "low." Tune the transceiver to the middle of the amateur band that you'll be using, or to the CB or GMRS channel that you plan to use.

What is a good reading SWR?

SWR Range Explanations. SWR 1.0-1.5: The ideal range! If your SWR is under 1.5, you're in great shape. If you're at 1.5 and really, really want to drop down to closer to 1 it's likely possible to do with addition tuning, different equipment or a different mounting location.

This Is How To GET SUPER LOW SWR ON YOUR CB RADIO!!

How do you lower the SWR on a dipole antenna?

To raise the frequency of minimum SWR, trim the antenna shorter. Cut each of the dipole's segments by equal amounts so that the two halves maintain equivalent lengths. If the minimum SWR is minimized at a higher frequency than desired, you must lengthen the wire segments.

What does an SWR reading of 4 1 indicate?

What does an SWR reading of 4:1 indicate? Loss of -4 dB.

Does common mode current affect SWR?

While it can affect SWR and the current flowing in that path be affected by SWR, high SWR does not cause and low SWR does not prevent unwanted common mode current or RF in the shack. Most antennas are neither perfectly balanced nor perfectly unbalanced.

How do you calibrate a SWR meter?

Turn the SWR calibration knob fully counter-clockwise. Key the microphone and, while continuing to depress the talk button, adjust the calibration knob so that the needle touches the "SET" mark on the meter. When the needle reaches the "SET" mark, flip the switch to "FWD"

Can a pinched coax cause high SWR?

Damaged coaxial cable is a big reason behind high SWR readings. A coax can get twisted, shorted, or pinched while routing through the vehicle. It might come damaged when buying from the market. Hence it is essential to check your coax cable thoroughly before purchasing.

Does coax length affect SWR?

Coaxial Cable Length Does Not Change Antenna SWR.

Does SWR affect reception?

Simplified answer: There is no relationship between SWR and receive performance. There is one condition for this simplification to be true: the received RF noise floor must be above your receiver's noise floor.

Why does my CB squeal?

Excessively high SWR may cause squealing (and also results in short range). Try running a ground wire to a screw on the side of the radio. If you are using a power microphone, try turning the gain down. Also try using the original microphone.

How do you ground a CB antenna?

Ground Your Antenna Mount

To ensure a good ground, check that your mount has a direct metal-on-metal connection to your vehicle's frame. Depending on the location of your mount, paint or powder coating can interfere with this connection. If this occurs, you'll need to scrape a bit of the paint or powder coating off.

How do I adjust my antenna frequency?

Attach the radio to the transmitter socket on the SWR meter using a coaxial cable. Attach the antenna to the antenna socket on the SWR meter using a coaxial cable. Set the radio to minimum power and to FM or CW mode. Tune to the lowest band available.

What causes common mode current?

Common mode current is most commonly caused by improper feedline installation or antenna design. The feedline, in effect, behaves like two very different transmission lines connected to the antenna and equipment at the same time.

How much power does a 2 1 SWR lose?

A VSWR of 2:1 means that with 10,000 watts transmitted, about 1,111 watts is reflected back towards the transmitter. If 100 percent of the transmitted power is reflected, the VSWR is infinity.

Is it OK to coil coaxial cable?

There's nothing inherently wrong with “looping up” extra coaxial cable. In fact, a neatly wound coil of coax can function as an air-core choke balun (“ugly balun”) which is useful for some antenna systems when located at the feed point of the antenna.

How does the length of a matched transmission line affect the SWR?

Line length doesn't matter when the line is properly terminated, the input impedance will remain unchanged with varying lengths of line. High SWR on a line with high matched-line loss will produce significant additional loss on the line.

How high should a dipole be off the ground?

For best results, dipoles should be at least 1/2 wavelength above ground level. For the lower bands, especially 160-40 meters, this can become impractical--place your dipole as high as your situation allows.

How long should my dipole antenna be?

When determining how long to make each leg of a Dipole antenna, dividing the frequency in MHz into 468 will give the overall length. To find the half wave, divide that number by two. This will give you the length of each leg of the antenna.

How do you increase the gain of a dipole antenna?

In order to increase the gain of an antenna, you need to concentrate its effectiveness in the required direction. Two common methods are to concentrate horizontal beamwidth by adding reflectors and directors, thus creating a Yagi beam.