CB Antenna Fitting?

Does anybody know which is the best way to "wire up" the cable from the antenna to the CB? I want to fix the antenna to the rear left, just above the light fixtures (more or less within the yellow box in the photo below) and I want to run the cable so that the connector comes out somewhere one the front center panel near the radio.

O Bife said:

Does anybody know which is the best way to "wire up" the cable from the antenna to the CB? I want to fix the antenna to the rear left, just above the light fixtures (more or less within the yellow box in the photo below) and I want to run the cable so that the connector comes out somewhere one the front center panel near the radio.

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Good place to catch any overhanging bits of tree. I'd put it the other side

Datatek said:

Good place to catch any overhanging bits of tree. I'd put it the other side

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LOL Maybe in the UK, but as I live in Portugal...

O Bife said:

LOL Maybe in the UK, but as I live in Portugal...

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So you do, missed that:doh:

Datatek said:

So you do, missed that:doh:

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It happens to the best of us, especially on a Saturday afternoon

What I would really like is for some sort of diagram (not too technical either) showing what and how to install the antenna cable. If it's things to do under the bonnet I can usually get by with a half decent manual, but when it comes to wiring etc within the cabin...

cable would be rg58, connector plugs for cb end pl259, the antenna end depends on the type of mount you choose. centre core of the cable goes to center pin of the connector and the shield braid to the casing of the connector. you cant really go wrong. you will need an adjustable mount to get the antenna vertical.

Don't mount it low down on the side. For 2 reasons. Firstly, CB operates as line of site communications. The higher the antenna, the more range you get. Secondly, the radiator (the vertical part of the antenna) will be running close to the ground (car body) so you will not be able to tune it in and will get hopeless performance and a SWR that will probably damage the radio or cause it to operate at reduced power to protect it's finals.

When you do install it, you need a SWR meter to correctly tune the antenna to the radio as too long or too short an antenna will cause the power from the radio to be reflected back in to the radio down the coax. From memory, a SWR of 2.1:1 is about 11% loss. 3.1:1 is about 25% loss and starting to risk the radio. You need as close to 1.0:1. You can't just chuck an antenna on a car and expect it to work. It probably will, but not very well.

Now, with radio ham hat removed: If you only want to talk to your mate in the next car 100m away, just chuck the antenna on the body and off you go

PL-259 fitting.

Nik

You could follow the cable run of the CD changer (if fitted).

It's mounted just below where your yellow box is in the boot, and ends up in the centre console, right next to the radio...

tufty said:

cable would be rg58, connector plugs for cb end pl259, the antenna end depends on the type of mount you choose. centre core of the cable goes to center pin of the connector and the shield braid to the casing of the connector. you cant really go wrong. you will need an adjustable mount to get the antenna vertical.

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Hi Tufty, thanks for that, but that part I know already. It's the actual getting the antenna cable from one end of the car to the other that is bothering me.

NikTheGeek said:

Don't mount it low down on the side. For 2 reasons. Firstly, CB operates as line of site communications. The higher the antenna, the more range you get. Secondly, the radiator (the vertical part of the antenna) will be running close to the ground (car body) so you will not be able to tune it in and will get hopeless performance and a SWR that will probably damage the radio or cause it to operate at reduced power to protect it's finals.

When you do install it, you need a SWR meter to correctly tune the antenna to the radio as too long or too short an antenna will cause the power from the radio to be reflected back in to the radio down the coax. From memory, a SWR of 2.1:1 is about 11% loss. 3.1:1 is about 25% loss and starting to risk the radio. You need as close to 1.0:1. You can't just chuck an antenna on a car and expect it to work. It probably will, but not very well.

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Thanks for that Nik, but as with Tufty above, that part I know. My problem as said above is how to "lay" the cable from the back to the front, but thanks once again.

MrGorsky said:

You could follow the cable run of the CD changer (if fitted).

It's mounted just below where your yellow box is in the boot, and ends up in the centre console, right next to the radio...

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That has crossed my mind. The only problem I might come into is that my CD Changer is on the right hand side of the "boot" and at the moment, I am going to be fixing the antenna on the left.

Back to NikTheGeek. I have thought about sitting the antenna to the roof, between the sunroof and the front window, but due to two things I am leaning to the rear end fitting.

• I have be told by a few mates that roof fitting tend to cause problems in the long run with water seepage.
• As the roof is aluminum I will have an earthing problem.

I would prefer the roof mount as it means the best foot print for the signal and also it would mean less coaxial.

If I do end up going with a roof mount would I be better off with a 34" Springer than the 61" Springer I was intending to fit to the rear?

I have also thought about fitting it further up from what is shown in the attached image above, on the "vinyl" part of the pillar. I know that I will have to add a support plate on the inside as that section isn't that strong/thick, but that isn't a problem.

(PS: Before anybody starts to say I would be better off with something like a Sirio etc, forget it. Those higher end antennas tend to grow legs a lot over here!)

O Bife said:

The only problem I might come into is that my CD Changer is on the right hand side of the "boot" and at the moment, I am going to be fixing the antenna on the left.

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Is yours not an original CD changer? I thought they were all mounted on the left hand side of the boot.

Anyhoo, if you get the cable in the car, you could easily run it under the carpets in the boot, and then along to the front under the tread plate things in the doorways. There will already be a load of wires going that way I suspect, they just gently pop off. Then when you're in the front footwell, just cable tie it up out of the way and in to the centre console.

If you mounted it in the middle of the roof, you could run the coax between the headlining, and come down the b pillar, and then under the carpets.

What about 80's style.... a mag-mount in the middle of the roof, and trap the coax in a back door?

MrGorsky said:

Is yours not an original CD changer? I thought they were all mounted on the left hand side of the boot.

Anyhoo, if you get the cable in the car, you could easily run it under the carpets in the boot, and then along to the front under the tread plate things in the doorways. There will already be a load of wires going that way I suspect, they just gently pop off. Then when you're in the front footwell, just cable tie it up out of the way and in to the centre console.

If you mounted it in the middle of the roof, you could run the coax between the headlining, and come down the b pillar, and then under the carpets.

What about 80's style.... a mag-mount in the middle of the roof, and trap the coax in a back door?

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1st things 1st, I'm living in Portugal and my P38 is a locally bought LHD, hence the CD changer on the right and me wanting to fit the antenna on the left rear (if I do not roof fit it)

As for the Mag-mount:

1. Simply put, I don't trust them especially when you take into account the cobbles and the amount of off-roading I do.
2. I like to have any wiring inside. No roof rack mounts nor any of those bumper/spare tire mounts. No matter how well tied down, with the brush I go through some times any protruding cable stands a good chance in getting torn off.
3. With those Mag-mounts, you're going to have to run the cable into the cabin somehow and that means unless you drill a hole for it (in which case you might as well use a normal roof mount) it will have to go in via a door, window or sunroof. In my opinion that either does the coaxial in and or starts to "force" the door or sunroof.

Getting back to the Roof mount option. I have be told that the P38's roof is aluminum and therefore I should use a ground-plate and also treat the "naked" aluminum to stop any oxi forming. Is that much of a problem do you think?


Also, is there room up there considering I have a sunroof and I would like to fit it in front of it?


And last but not least, is it rather straight forward in running the coaxial down the front pillar?

fecking hell...

makes me sad reading this....

mag mount!!! on ali!!!??? if you invented a magnet that works on ali then you some dude!!

and ground plane..ali is superb!!better conductor than steel..works better..

as for getting cables to front of car...if you have a long whip..ie your 1/4 wave or w.h.y then push that under carpet from front to rear(you can just go under each bit of carpet at a time if you wish.attach cable (do it well) with insulating tape and pull back..easy.

as others have suggested its easy enough to run a coax under the carpet.

however i differ on your opinion of bumper mounted. if you're going through that much trees and brush how come you don't have brush guards and yet not a scratch on the car? if you have brush guards or bull bars then that's a good place to mount. and if not I've seen fittings that start on the rear bumper, curve right over the car and are tethered to the front bumper or brush guard, and that's the army. you would drill a hole in the floor of the boot, maybe in the spare tire well and fit a rubber grommet to pass your cable through and paint over with some liquid silicon. Would be mostly water tight, certainly safe from rain and car-washes although I don't know how well it would hold up to wading.

Well I never knew the roof was ally. So it was worth contributing to the thread to read that!!

Fitted mine through grille ran an earth wire to body and passed lead up inside wing and through passenger door by hinge ' cb mounted on the side of tunnel using existing screws coaxle runs under seat to cb .

The roof is steel, I use a mag mount behind the sunroof and shut the cable in the rear door. Not very neat but it's okay for a temporary fit.

NikTheGeek said:

Well I never knew the roof was ally. So it was worth contributing to the thread to read that!!

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It's not! Call me sad, but I've just been out with a magnet. On my 2002 DHSE, the roof is most definitely steel, as is the bonnet and front and rear wheel arches. But the 4 doors and tailgate are all aluminium.

I still didn't know there was any ally on them. I thought that was only Defenders. So I still learnt summut

Nik

Same as disco Steel roof and body framing. doors and panels are Ally.

I thought I'd read somewhere that the roof was steel, but I couldn't find where I'd read it.

Anyhoo, if you mount it in the roof and run the cable down the 'A' pillar with the sunroof drain, I think that it'd come out behind the front wheel arch liner. From there you can come back in to the cabin through the bulkhead. There are plenty of wires already going through it, so you should be able to sneak some coax through a grommit with other wires I'd have thought.

If you're going to make a neat job of drilling holes in your roof, you'll have to take the roof lining out anyway, with that out you'll be able to see the the best route to take I'd have thought. Taking the roof lining out is pretty quick (I've read!).

If you chose to mount in front of the sunroof (I suspect the roof is strongest there), check for clearance of the sunroof motor before you start drilling! You might be able to see the clearance by taking the cabin lighting unit out, and looking up through the hole...

Thanks to those who have found that the roof is in fact steel.

Nik, sad would be those who think you sad for doing what you did. LoL

MrGorsky, (kicking myself here) I only just had the ruddy head lining re-done! Mind you, before having it done I had had a good look around the the sunroof motor fittings and it looks like there is room just in front of it. There also seems to be enough space (depth) just there between the actual roof and the head lining.

In that case I should be able to get away in fitting just a good old dome mount like this one:


Now all that has to be decided is antenna length. As I said further back in this topic, I have been leaning towards a 160cm (5') Springer like this one:


But now, if I do go ahead with a roof mount, what length would I be better off with, a 5 footer or a smaller 3 foot Springer?