GMRS Base Antenna Spacing

[WSDB540]

I have a CB base antenna up. I want to put up a GMRS base antenna on a separate pole. How far apart does it need to be away from the CB antenna?

Thanks

[WRYZ926]

General rule of thumb is to space antennas apart by 1/2 to 1 full wave length. A full wave length for CB is 11 meters/36 feet. A half wave length is 5.5 meters/18 feet. So you would want your GMRS antenna at least 18 feet away from your CB antenna horizontally. You can put antennas closer together vertically if you have the space to go up and down.

[MSnow]

I had on my truck dual firesticks on each bed rail and then had my mxta26 on the roof about 2.5ft away from each firestick with no issues.

[BoxCar]

Antenna spacing is critical when the frequencies are within the same band or one (or both) are using high power. CB is essentially HF (below 30 MHz) while GMRS is UHF (462 - 467 MHz) or 20 times higher in frequency. Your spacing should be at least a quarter-wave length of the UHF channels or 15 CM.

[WSDB540]

18 hours ago, WRYZ926 said:

General rule of thumb is to space antennas apart by 1/2 to 1 full wave length. A full wave length for CB is 11 meters/36 feet. A half wave length is 5.5 meters/18 feet. So you would want your GMRS antenna at least 18 feet away from your CB antenna horizontally. You can put antennas closer together vertically if you have the space to go up and down.

I can go higher for the GMRS antenna thanks for the help.