CB radio poor range

[Gary820]

I've got the antenna mounted to the top of the A bar, get 1.5 to 2 miles range. No issues with transmitting or receiving.

 

[StarCruiser]

A bigger antenna often aids reception and transmission as well as getting it as high as possible. Both rather tricky on a vehicle. Long antennas get in the way and whip about and the only way to gain height is to drive to a high spot.

Many in Sussex 4x4 Response have gained amateur radio licences which allow for greater power on the 2m band. 10 watts on the foundation licence, then 50 on the intermediate but to get any real distance you still need height and a good antenna. Vehicle mounted I'd say 5 miles is practical on 10 watts from a moving vehicle with landscape and buildings around.

 

[clivehorridge]

I've got the antenna mounted to the top of the A bar, get 1.5 to 2 miles range. No issues with transmitting or receiving.

How long is yours Gary? The bloody antenna I mean

 

[Crispin]

Sounds like you need a "108 whip" those were the things to have in the 80s and 90s!

Sounds like you might be down on power with that. Tried a cheap power meter?
Could it be that yours is slightly off frequency and the fact that you're actually getting anywhere at all is just harmonics?

 

[Gary820]

How long is yours Gary? The bloody antenna I mean

Not too long, i think it's a 48" (80 not here to check)
Can see it in the pic.
I don't use a Springer antenna and this one doesn't whip around all over, it barely moves under normal circumstances but flexes well when branches etc catch it.

 

[clivehorridge]

Not too long, i think it's a 48" (80 not here to check)
Can see it in the pic.
I don't use a Springer antenna and this one doesn't whip around all over, it barely moves under normal circumstances but flexes well when branches etc catch it.

View attachment 126489

Mmmmm, similar to mine.... I don't have the springy thingy either.

 

[pyemaster]

I run a T1000 off a bumper-mounted 4ft top-loaded Firestik, and get a solid range when mobile, up to around 8km. The conditions have to be right (not surrounded by buildings, etc), but so long as one of us is in the clear and not sunken in a valley, comms is pretty good. I made sure my SWR was tuned in a big, flat, empty area, on UK 1, 19, 40 and EU 1, 19, and 40, all below 1.5.

Owen

EDIT - I should add some of the breakers talk from big-antenna base stations, which certainly helps them!

 

[Bat21]

Eureka.... 'I've found it'

All the previous installations were lacking a decent 'ground plane'

I have fabricated a solution which now gives me almost a 4 mile range which is a lot better than the <1 mile one for the last 10 years.
A 200mm x 600mm plate fixed to the top of the front ARB with the Sirio antenna fixed in the centre.

 

[StarCruiser]

Well done Bat.
Pleased you've got it sorted.

 

[clivehorridge]

Eureka.... 'I've found it'

All the previous installations were lacking a decent 'ground plane'

I have fabricated a solution which now gives me almost a 4 mile range which is a lot better than the <1 mile one for the last 10 years.
A 200mm x 600mm plate fixed to the top of the front ARB with the Sirio antenna fixed in the centre.

I think that begs a photo Bat, for positioning etc., if there's any chance, sounds good though!

 

[Bat21]

Here you go Clive, function clearly takes precedence over form here..... but it has made a huge difference to the range.

 

[clivehorridge]

Cheers Bat, not knowing what I'm on about, in a technical sense, it looks like you've made a "connection" between ground planes by adding one to the antenna, and thus transferring ground plane to the bonnet.

That may be a load of crap, but it kinda has some logic to it.

Thanks again!

PS how d'ya get to the bonnet safety release catch now?

 

[Bat21]

The plate is essentially the 'Ground Plane'. I kept it as close to the bonnet as possible to allow the bonnet to act as a plane too.
The plate has a small earth wire running from it to the chassis too as I didn't want to grind off the powder coating from the ARB.
When the antenna was mounted just on the ARB spot light brackets there was next to nothing to 'bounce' the signal up and out, hence the previous poor range.

 

[clivehorridge]

Makes sense, how do you get to the bonnet release now, it looks very tight in there now...?

 

[Bat21]

Bonnet lifting is simple, there is enough room to put my hand under the plate and release the catch as normal.

 

[clivehorridge]

Bonnet lifting is simple, there is enough room to put my hand under the plate and release the catch as normal.

Aha, that's OK then, it's not so evident from the photos.

Maybe I need a trip to the piece of steel 200 x 600 shop...

mmmm, they do some multi-drilled plate in various sizes in the local B&Q equivalent here, I don't suppose "colander" type holes would spoil ground plane, would they?

 

[Bat21]

.... Maybe I need a trip to the piece of steel 200 x 600 shop...
mmmm, they do some multi-drilled plate in various sizes in the local B&Q equivalent here, I don't suppose "colander" type holes would spoil ground plane, would they?

It needs to be solid Clive. It is the solid plate that is bouncing the signal up and out..... if it was full of holes I suspect it would be less effective.

 

[clivehorridge]

It needs to be solid Clive. It is the solid plate that is bouncing the signal up and out..... if it was full of holes I suspect it would be less effective.

I take your point...

They're only little 3/16" holes, mind...

 

[Bat21]

.... They're only little 3/16" holes, mind...

That might mean you will lose 3/16th's of your transmission signal

 

[Towpack]

I don't think a few holes would make much difference. A ground plane can be made from a few radially spaced rods (ideally 1/4 wave length long). Siting whip antennas on a vehicle is very much trial and error as there are so many influencing factors.