CB Radio

[joe112]

Hi All,

I have just purchased a new aerial for my CB... Its a half length one so not as long as normal...

My problem is that since I have started using it I seem to have very poor transmition/reception. When I use the Squelch button I cannot get the normal "crackle" at the bottom end and I don't think its transmitting more than 1/2 mile...

Could it be that it isn't SWR'd in... If so how do I do that??

Any other sugggestions greatly appreciated

I know this question isn't about a surf but the radio is fitted in a surf so let me off please!!!

Cheers

Joe

[stormforce]

Hi All,

I have just purchased a new aerial for my CB... Its a half length one so not as long as normal...

My problem is that since I have started using it I seem to have very poor transmition/reception. When I use the Squelch button I cannot get the normal "crackle" at the bottom end and I don't think its transmitting more than 1/2 mile...

Could it be that it isn't SWR'd in... If so how do I do that??

Any other sugggestions greatly appreciated

I know this question isn't about a surf but the radio is fitted in a surf so let me off please!!!

Cheers

Joe

hi joe i think you will need to swr it in as it is a entirely differant antennae
you will have to connect the meter up to the ariel and then there should be an adjuster on the ariel which you need to adjust to bring the meter to the correct reading this is how i used to do it 20 yrs + ago but as far as i know it hasn't changed much

[Andy W]

You can get cheap SWR meters from ebay. It's a ten min job, usually with a Hex Key.

[joe112]

You can get cheap SWR meters from ebay. It's a ten min job, usually with a Hex Key.

Shop I purchased it from say it is already SWR'd in... it shouldn't need any alteration - I thinks they talkin B****cks, Could it be anything else??

just for the record... Works fine on old aerial... just looks s***e
Also purchased new mount (screws to Roof rack) came complete with new Co-axel

Any help appreciated

Joe

[Andy W]

They are talking rubbish, each set is different and the SWR alters due to different size ground planes and length of coax etc. It will need checking again you can bet on it.
Make sure it is grounding properly to truck either by mag mount or other clamp (don't know your set up).

Andy

[mark g8awo]

No antenna is tuned when you get it out of the packet they come with a near resonance but you need to fine tune it with the aid of an SWR bridge meter.

To make things easier first you set the radio to the centre of the band and find the swr reading their, without resetting the meter goto the ends of the band and find the reading on the meter. If you find the reading is lower at the top of the band you need to lengthen the aerial and the same applies to the other end but in the reverse...

If you were more local to me i have the best box available to set these aerials up without firing the radio up once but you are not going to spend £300 on a box to do 1 aerial.

[joe112]

Now Its Makin Sense!

Right.... I have it attached to the roof rack using a mirror mount... The roof rack is rubber coated and is on rubber feet so the so the aerial is not touching the van at any point... no metal to metal contact... Is this the problem than?????


God you guys on ere are good!!!!

[Maverick]

I'm not an expert, but by my understanding (get ready for everyone to correct me) the vehicle makes up the ground plain, i.e. effects the quality of the reception/transmission. My aerial is a boot mount, mounted on the bonnet, with an extra earthing strap to a good ground on the chasis. I've never SWR'd it, but it appears to work OK.
I think (please correct me if wrong) you need to have the aerial actually connected to the bodywork, and this might be the source of your problem.

[mark g8awo]

Right.... I have it attached to the roof rack using a mirror mount... The roof rack is rubber coated and is on rubber feet so the so the aerial is not touching the van at any point... no metal to metal contact... Is this the problem than?????


God you guys on ere are good!!!!

You do need to make sure there is an earth...

The comms shop i work in at the weekend does a very good earth strap that not only looks good but it works

[Tallyman]

If you want a good ground plane, use a mag mount in the centre of the roof. THat way you'll get good signal projection in most directions. At least that was how I set up my original set in the early 80's. Still got the old box knocking around in the loft somewhere.

[mark g8awo]

If you want a good ground plane, use a mag mount in the centre of the roof. THat way you'll get good signal projection in most directions. At least that was how I set up my original set in the early 80's. Still got the old box knocking around in the loft somewhere.

Mag mounts dont make good ground planes not on HF as i said before the better the earth the better the radiated pattern but if you can get it into the middle of the roof on the roof bars it will be the best option but you will have wires trailing mine is mounted on the spare wheel hanger, I worked a guy in thailand the other day on 21Mhz

[da SLUG man]

i've got twin co-phase aerials... worked well on the truck, but apparently not so good on a roof of a car... haven't actually wired them up yet!


all depends what you want it for... only used mine for chatting to mates when in "convoy" or when passing each other (only 5 mins chat when you're parting at 112mph!)

got some PMR handhelds that we usually use when mobile. (they're good fun for winding up the local motorbike instructor!)

[BUSHWHACKER]

Mag mounts dont make good ground planes not on HF as i said before the better the earth the better the radiated pattern but if you can get it into the middle of the roof on the roof bars it will be the best option but you will have wires trailing mine is mounted on the spare wheel hanger, I worked a guy in thailand the other day on 21Mhz

Was he radio controlled then?













I thought it was funny

[TonyN]

Was he radio controlled then?

I thought it was funny

Not bad, I'd go for the subtle 'altered quote'......

I worked a lady-boy in thailand the other day

..... to get a laugh though.

[da SLUG man]

I worked as a lady-boy in thailand the other day

let's have a quote comp!