Antenna in Defender

[discomonkey]

Evening all

I am going to re-instate the CB to the Defender 90. I took it off a few years ago as I assumed hardly anyone used them anymore but it seems I was VERY wrong! I installed a flashing beacon in place of the antenna which was in the middle at the back of the roof on the Defender. Since then a sat nav has been added and with it an antenna that does the radio, sat nav and DAB. This is right next to the beacon where the CB antenna used to be.

Question is, how far away from the car radio aerial does the CB antenna need to be? The antenna I have is around 1.5m long and looks VERY similar to the Thunderpole Orbitor, although there is nothing on it to say that it is one. I am assuming I should get a decent range with this, although I would have preferred a slightly shorter one.

I am hoping to be able to just use my little Midland 42 for now, I may get a fixed CB if we start using them more. I cannot find the one that was originally in the Defender when I bought it, it's probably here somewhere! I have just ordered some cable and an SWR meter from Thunderpole so hopefully will have something working later in the week if I can decide where to reinstall the antenna. The little antenna on the Midland 42 has a range of about 200 meters!

Many thanks.

[stampman]

you can install the cb antenna instead of the radio antenna and get a splitter from our sponsors which will run the radio from the cb antenna with no problem at all

[discomonkey]

you can install the cb antenna instead of the radio antenna and get a splitter from our sponsors which will run the radio from the cb antenna with no problem at all

The only problem with that is the radio antenna (one of the shark fin type things) also does the Sat Nav so I need to keep it. How far away do you think the CB antenna needs to be from the other one?

[stampman]

does not matter as the wont interface

[discomonkey]

does not matter as the wont interface

Do you mean it won't interfere?

[stampman]

yes

[discomonkey]

Thanks very much, typical internet gives contradicting views! Wherever I put it I will need to get a decent earth as Def3nder roofs are aluminium. Do you sell kits for that or do people just run a decent size cable to the battery?

[discomonkey]

All setup - thanks for the advice

[discomonkey]

One last job to do which is run an earth wire from the antenna to the chassis. The chassis end is easy, but what is the easiest way to attached to the antenna? Was thinking a jubilee clip but perhaps there is a better way ?

Many thanks.

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[stampman]

it should earth through the body work if the swr is ok then dont mess with it

[discomonkey]

SWR was about 2 on all channels, and went down when someone touched the aerial. The chap in the shop said Defenders need a chassis earth regardless of what anyone says.

What’s the best way of attaching one to the antenna

[stampman]

no its not if its 2 right across the band its fine dont mess with it to get it lower you would have to change the antenna as orbiter's pick up reflection from the body of the vehicle and is the cause of the reading

[discomonkey]

The bloke in your shop said 2 was no good and it needs an earth to chassis. I’ll do it with a jubilee clip or plate if it’s a secret how to do it. Just wondered if there was a better way.

I can’t eemember which way around it is, but I get about 1.5 and one end and 2 the other.

[stampman]

good luck