Minimum distance between antennas on trunk?
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mmckenna
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Yes, there will likely be interference if all three antennas are on the trunk. Issue would be that if you transmitted with the CB, some of the RF could overload the front end of the scanner. This would probably result in the scanner not being able to receive while you were transmitting.
Unlikely that a 4 watt CB radio is going to cause issues. The amount of signal lost in the coaxial cable is probably going to bring that 4 watts down quite a bit. Most CB's I've tested don't put out anywhere close to the full 4 watts anyway.
I'd recommend placing the CB antenna in the center of the trunk. Ideally put the scanner antennas somewhere else, but if they have to go on the trunk, put them out towards the edge. Don't be surprised if the scanners receivers become overloaded when transmitting, even with that separation.
Unlikely that a 4 watt CB radio is going to cause issues. The amount of signal lost in the coaxial cable is probably going to bring that 4 watts down quite a bit. Most CB's I've tested don't put out anywhere close to the full 4 watts anyway.
I'd recommend placing the CB antenna in the center of the trunk. Ideally put the scanner antennas somewhere else, but if they have to go on the trunk, put them out towards the edge. Don't be surprised if the scanners receivers become overloaded when transmitting, even with that separation.
Loss at 27 MHz is very low even in RG58. But I agree with everything else MM said.
Ideally, you want the antennas more than a quarter wavelength away. Of course, that's not easy to do on CB, but the CB power is low, so you can get away with closer spacing there.
Basically, put them as far apart as you can - especially for those that transmit higher powers.
Ideally, you want the antennas more than a quarter wavelength away. Of course, that's not easy to do on CB, but the CB power is low, so you can get away with closer spacing there.
Basically, put them as far apart as you can - especially for those that transmit higher powers.
Antennas on trunk.
Just put one scanner antenna in the middle, one on the side and the CB antenna opposite side of the trunk. As much physical separation as possible.
Next to each other, you could have problems with your scanner as others have said. If you get too much attention on the "antenna array" on your trunk, see below:
It may be hard to see in my picture, but on the far left is a VHF antenna, UHF "Phantom" antenna and a GPS antenna right next to each other. I got tired of local law enforcement pulling me over to see "who did your antenna install" as many of their vehicles have 3 foot whips bouncing around on them. I had the antennas spaced out to work better, but they ended up calling a lot more attention than I wanted.
They work very well right next to each other, and have very minimal loss. (VHF range is about 12 miles, and UHF is about 8-9.) The window antenna mount seen is the old On-Star mount, and the four on the roof were for direction finding that day, those are not left on the car.
Just put one scanner antenna in the middle, one on the side and the CB antenna opposite side of the trunk. As much physical separation as possible.
Next to each other, you could have problems with your scanner as others have said. If you get too much attention on the "antenna array" on your trunk, see below:
It may be hard to see in my picture, but on the far left is a VHF antenna, UHF "Phantom" antenna and a GPS antenna right next to each other. I got tired of local law enforcement pulling me over to see "who did your antenna install" as many of their vehicles have 3 foot whips bouncing around on them. I had the antennas spaced out to work better, but they ended up calling a lot more attention than I wanted.
They work very well right next to each other, and have very minimal loss. (VHF range is about 12 miles, and UHF is about 8-9.) The window antenna mount seen is the old On-Star mount, and the four on the roof were for direction finding that day, those are not left on the car.
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Marshall KE4ZNR
Marshall KE4ZNR
N3JI
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How much transmitting are you going to be doing?? And when you are actually transmitting, how much are you listening to scanners? I don't think this will be as bad as you think it will be. I have my 800 MHz scanner antenna on my front windshield on the passenger side where my broadcast radio antenna is (on the fender). My VHF/UHF antenna is mounted on the driver side fender opposite of the broadcast radio antenna. My 900 MHz antenna on the windshield opposite the scanner antenna on the same side my VHF/UHF antenna is. So both receive only antennas are on one side, my transmit/receive antennas are on the other. Seems to work. Although I notice that sometimes when I transmit on VHF (50W), it kills the reception on my HD radio. And I think there is some degradation on the scanner (listening to 850 MHz) when I transmit on 900 MHz, but since the volume is down since I'm paying attention to my conversation it's hard to say how bad it is.
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