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Multiple CB radios in the same vehicle

Twinklz

Forum Member
Joined
Feb 4, 2014
Messages
551
Location
Perth, Western Australia
Car Year
2008, 2009
Car Model
D22 Navara 2.5 CR ST-R, Impreza R-spec
Transmission
5 Speed Manuals
I'll be installing two more CB's in my Jackaroo soon and was wondering if there's any problems with running multiple radios in close proximity on the same channels?
 
When using my handheld and in-car CB on the same channel I can get feedback. When on different channels my handheld seems to interfere with transmission from my in-car.
 
As I understand things, the channels are all side bands. The carrier signal frequency is the same for them all.
 
shouldn't be a problem, if you make sure your using good quality braided coax, good aerials and they are positioned so as not to reflect off of each other. What are you thinking of a uhf a 27mhz and an hf?
 
I'll be installing one in the boot, for use when I'm cooking or otherwise unable to get to the drivers section radio, and another radio for the back seat, because that will be turned into a storage section and will have a cargo barrier stopping me from reaching the front and rear radios. I'm going to install a GME TX3100 and GME TX3500 with GME antennas, 6.5DB, how much interference can I expect?
 
A bit, spacing them is the easiest way to aviod most reflection, so say one on the front of the car one high off the rear of the vehicle opposite side.

Why not just buy another couple of hand pieces and wire them in? the control box would be pretty simple, or just put them all in parallel and make sure no ones ever using more than one.


There's also just putting them all on the same aerial through a uhf splitter. that's a little more stuffing around to do right though, as you'll need a specialy auto switch or multi-position remote switching unit. Which is still as reasonably simple control box to make. wiring is a ***** to run tho as there's alot more of it. plus each switch would need to go to a dummy load when not on an antenna.
 
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So if I space the antenna out the interference will be reduced?
 
Follow IDWs advice on the multiple hand piece if you insist on having 3 transmission stations in the 1 vehicle. Better yet buy a 5W handheld unit and clip it to your belt when you're not at the helm, that way you can remain in contact even when nature calls or for some reason you had to leave your passenger at camp or in another vehicle.
 
So if I space the antenna out the interference will be reduced?

To an extent, it'll tune the reflective shadowing effect to a longer wave length the wider they're spaced,you've got to remember it's all a bit of chasing your tale, unless the aerials on the roof, anywhere you put an antena on a car or 4wd makes it directional. Personally I'd go with multiple hand pieces on agme tx3345
 
Gidday Twink

Follow IDWs advice on the multiple hand piece if you insist on having 3 transmission stations in the 1 vehicle. Better yet buy a 5W handheld unit and clip it to your belt when you're not at the helm, that way you can remain in contact even when nature calls or for some reason you had to leave your passenger at camp or in another vehicle.

I agree with the reservations expressed by both Id and ST.

The solution suggested by ST, is really a far better one, IMO. With this, you do not end up with a car full of CB units, aerials everywhere, and the huge problems with wiring that Id referred to.

While avoiding the problems, you end up with a more flexible and sensible practical solution.

I have a 5W unit in my car and two 2W hand held units (came as a pair at a price I couldn't refuse ... :iconwink:). Doesn't hurt to have a spare, either.
 
It comes down to personal preference, last time i was waiting for someone at a campsite, They were out of range of everything except the vehicle mounted CB'S. Also, I find the Jackaroo looks awfully good with multiple antennas on it. I was planning on an antenna in the left hand rear corner of my basket, an antenna on the top right hand corner of my roofbasket and one on the lefthand corner of my 'roo bar, i figure that will avoid the interference as much as possible, yes?
 
About as much as is reasonably practical, for the setup you want
 
Twinklz, if you remind me at Safari, I'll introduce you to some of the SOS fellas if we get time. Those old guys REALLY know their radios and can basically tell you anything and everything you could possibly want to know.
Last campfire, they were working out which channels would interfere at Safari due to the powerlines running alongside and where to put repeaters for different channels... I'm normally pretty bright (i like to think) but it was just amazing that they could know all that off the top of their heads, i couldn't follow it.
 
I know this is a late response, but avoid putting a receive antenna at 1/4, 1/2 and full wavelengths distance of that receive frequency within a transmit antenna.

What does that mean in English???

Need to know what radios you will be running first as in HF, UHF, AM
 
Whilst this has been shelved for a while ( looking for a rental, takes priority over mods) I plan to run UHF Radios, 6.5DB
 
Also, if you're running 3 different UHF radios, i'd suggest (suggestion only) getting 3 different dB aerials?
and if they're the screw-on, screw-off type, you could even swap them around depending on the terrain and which one you're using most often.
I have a 4.5 (i think) dB on Scooby and find it's got an excellent mix of highway distance (easily does visual range) without compromise in radio-unfriendly terrain (it reached you and Interceptor through a good Km or two of dense, slightly hilly pine forest at Wellington without difficulty)
just my 2c
 
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