How to Adjust a Cobra CB

By Chyrene Pendleton

Adjust your Cobra CB to give and receive service, like weather warnings.
i snowy road image by samantha grandy from

Starting out as a small TV repair business in 1948, Cobra Electronics Corporation continues to design and produce electronics products for consumers worldwide. Some Cobra products include radar detectors, GPS navigation, two-way radios, marine electronics and CB radios. Cobra presented the first Bluetooth wireless CB radio in 2008 for safe communication while driving. Your Cobra CB helps you during emergencies, allows you to communicate with your friends and family, warns you and allows you to warn others of weather and traffic problems. Properly adjusting your Cobra CB will help your CB service you with clear signal reception for years.

Setting Squelch and Dynamike

Set your Cobra CB for squelch by adjusting the "Squelch" control counterclockwise until you can hear noise. Squelch eliminates or reduces noise in a CB radio when you tune the receiver to an unused frequency. Turning the "Squelch" control counterclockwise allows all of the signals in.

Turn the "Squelch" control clockwise until you hear the noise stop. This sets your Cobra CB to the Desired Squelch Setting (DSS).

Adjust the Dynamike clockwise to reach the maximum voice volume. The Dynamike controls the sensitivity of the microphone's audio level. From the maximum voice volume, you can reduce the Dynamike if necessary.

Adjusting ANL and NB Switches and RF Gain

Locate the Automatic Noise Limiter (ANL) switch on your CB front panel and turn it to the "ANL" position to help reduce noise made by the electronics in your vehicle.

Turn the RF Noise Blanker (NB) switch found on the front panel of your CB to the "NB" position to increase noise filtration. The NB reduces constant noises like interference from your vehicle's ignition. Turn the NB switch to the "Off" position to turn the noise filtration off.

Turn the "RF Gain" knob counterclockwise to reduce the gain in areas where you find strong signals. Adjust the "RF Gain" knob clockwise to increase the gain where you find weak signals. The RF Gain helps you get the most out of the reception in strong or weak areas.

SWR Calibration

Close the doors to your vehicle and ensure you park your vehicle in an open area. Keep others away from your CB's antenna.

Select channel 20 on the front panel of your Cobra CB and turn the Standing Wave Ratio (SWR) switch to the CAL position.

Press the "Mic" button and while holding in the button, adjust the "SWR CAL" knob until you see the meter needle move to the right to the CAL mark, which looks like a down arrow.

Set the "S/RF SWR CAL" switch to the "SWR" position while you continue holding in the Mic button and read the SWR reading. Repeat this procedure for channels 1 and 40, so all of the channels checks for SWR. Ensure the meter needle appears as far to the left side of the meter as possible, never over the number three. Adjust the CB antenna height slightly up or down if necessary.