CB antenna too close to dual band antenna?

[FredTx63]

I'm thinking about installing an 11 meter radio & dual band VHF/UHF radio in my new truck. That'd mean two antennas on the roof. A puck mounted base loaded Sirio P5000 for 11 meters a few inches in front of the high mount rear brake light and an NMO mounted dual band antenna same position but closer to the front of the cab (but before it starts sloping down towards the windshield, so it's nice and vertical). This will mean probably 3-4 ft. between the two antennas. Is performance going to suffer because they're so close or will they not "see" each other since the antennas are resonant on different frequencies?

 

[midnight special]

my 2 meter base load is mounted above the dome/external brakelight on roof and my 102 whip is 2 foot back mounted on my tool box,, swr is perfect on both and i seem to get out real good on both,,, just my 2 cents worth,,

 

[AudioShockwav]

I have run a tribander on the roof with a 96" fiberglass antenna for 10/11 on the trunk with no problems before.
73
Jeff

 

[Low_Boy]

I was once told the only way mounting 2 antennas too close can give you trouble is if they are the same bands.

 

[M0GVZ]

They'll detune each other due to capacitive coupling so you may find you need to cut a bit off the CB antenna to get the SWR down as they'll appear electrically longer. The dual band antenna may be the most affected out of the pair, you'll definitely need to check the SWR on it.

 

[OldTech03]

I recently purchased a new F150 love this truck it's the 500HP version it's an all smiles and fast miles anyway I installed both the 2 meter dual bander along with a 2 meter dual band antenna on one side of the pickup it's mounted to a window bracket I made and the 11 meter antenna is mounted on the passenger side of the trucks bed tie-down mounting plate again I made a custom mount in my shop that would allow the locking tie-down plates to remain and the antenna mount slips in behind the Tie-down plate. The only trouble I had was with the 11-meter antenna. No matter what I did it would not fall below 2.5 so I modified the base with an adjustable matching system made from a gamma match rod that someone gave me and that allowed me to get to 1.2. Now my 2 meters doesn't like my 11 meter it tends to overload the 2 meters front end a bit but, in its defense, I run about 400 on 11 meters otherwise the match on 2 meters is 1.1 the antennas are about 4.5 feet apart.

 

[Rwb]

I recently purchased a new F150 love this truck it's the 500HP version it's an all smiles and fast miles anyway I installed both the 2 meter dual bander along with a 2 meter dual band antenna on one side of the pickup it's mounted to a window bracket I made and the 11 meter antenna is mounted on the passenger side of the trucks bed tie-down mounting plate again I made a custom mount in my shop that would allow the locking tie-down plates to remain and the antenna mount slips in behind the Tie-down plate. The only trouble I had was with the 11-meter antenna. No matter what I did it would not fall below 2.5 so I modified the base with an adjustable matching system made from a gamma match rod that someone gave me and that allowed me to get to 1.2. Now my 2 meters doesn't like my 11 meter it tends to overload the 2 meters front end a bit but, in its defense, I run about 400 on 11 meters otherwise the match on 2 meters is 1.1 the antennas are about 4.5 feet apart.

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looks darn nice