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lummers

Has anyone who has fitted a CB radio to their motorhome able to advise me the best place to fit the antenna and advise how to get over the lack of ground plane - autotrail mohecan. Does anyone have any experience of the on-glass type ariel..

spykal · Moderator

Hi

It is a long time since I had anything to do with CB but if you can get what was once the choice for fibreglass vehicles, a Firestick "No Ground Plane" antenna you could fit it almost anywhere ... if you have a rear ladder fix it to that .... the ladder may also act as a ground plane with a tuneable antenna. I think we have one or two CBers around who may have more up to date suggestions for you.

Mike

peedee

I have a 1/4 wave whip mounted on my Mohican wing mirror, it works fine.
You can also get artificial ground plane mounts. Have a look

Snelly · Eastern Rally Co-ordinator

Glass mount... don't waste your money.

Go for a mirror mount or if you want roof mount, try make your own ground plane out of a piece of sheet stainless steel. I was also told by a radio HAM, that you can use a mirror mount on ali roof bars if you have them?? Im sure DABS will correct me if thats wrong, I personally didn't quite know how a non conductive material would act as a ground plane, but apparently it does??

lummers

thanks to all for your comments.

Laikadriver

It was a bit of a hasstle, but I actually made my own 'groundplane'!

I purchased a very thin sheet of steel, 2' x 4' which I then welded a 'Sirio' mount in the centre. I then welded an earth bracket in one of the corners. The metal was then cleaned thoroughly and primed/ given several coats of white hammerite paint. I then added the vehicle registration onto the panel for added security.

The panel was secured to the roof using Sikaflex 221, so no holes have to be made. I then routed the CB coax, and a seperate earth strap via a route used for wires for the solar panel.
Fitted a 'Thunderpole SuperNova' antenna, which is extremely flexible and doesn't mind the odd tree branch!!

Total weight? 3kg

Total cost? approx. £60

SWR varies between 1:2 and 1:3 across 27/81 and CEPT, and because it is so high up I get much better range.

for more info, see:

CliveMott

Similar to the above but done a bit differently.

Take a foot(ish) square of 16 SWG aluminium and using countersunk screws bolt a bit of ally "U" channel to it to take the mobile mount. Glue the plate to the roof with Sikaflex and described previously. Then get a roll of air conditioning engineers adhesive backed aluminium tape, its about 5 inches wide and run a strip along the length of the MH overlapping the ally plate. Run another strip across the width of the Mh overlapping the ally plate. This system worked well on our old Dormobile Freeway back in the seventies.
This time (back in 1997) we had a full aluminium skin roof fitted to our autotrail Scout before the GRP top went on during vehicle build. The roof bars are all electrically connected via the fittings to the ally beneath and the antenna fit to the roof bars.

10:4 GB

sysinfo

Do people still use CB Radios? I remember back in the late 70s using CB on AM, and when the Government outlawed Am in favour of FM it lost its appeal.

tonka