Covert behind bumper Dipole CB aerial?

[sae70]

In an attempt to drill fewer holes in the new truck I've been searching and searching the net for an elegant way of having a CB aerial fitted that looks either very original equipment, temporary as in mag mount or covert. Now before you all start laughing these things are commercially available for use by Taxis, covert Police vehicles and surveillance, but I can't find anything that will cover the CB frequency range. I stumbled over a couple of radio nerds on a couple of forums talking of home made ones, but not in enough detail to be able to make one myself.

So thought I'd see if anyone knows where I could go and buy one from or get the instructions to make one or even two. One for the front bumper and one for the rear bumper

link to commercially available covert twig http://www.panorama-antennas.com/index.php?route=product/product&path=84_87&product_id=115

 

[Doodle]

I think the problem with a covert setup is that the performance will be very poor for CB especially when they're sat low down behind a bumper (possibly part of the reason why you can't find any). Those aerials you linked to are for TETRA units, which if I understand correctly works somewhat like GSM comms.

 

[wobbly]

Maplins sell a 1m tall cb aerial, thats about the least obvious ive seen.

For best tx/rx you need the aerial to be mounted as high as possible, and ideally central, so the vehicle acts as a groundplane.

if its for convoy type driving, you could use it on top of a wing - either where the existing car radio aerial sits, or if you have a snorkel you could mount it on that wing and then run it up adjacent to the upright.

Or....buy a handheld cb and use one of the dinky mag mounts when you need to use the radio.

The more covert you go, the less the radio will work effectively.

Pete

 

[Towpack]

A simple 1/2 wave dipole antenna, like the versions made commercially for covert use, would be too big at CB frequencies to easily conceal behind a bumper or anywhere else for that matter. I guess you could trim one down and use a loading coil or an ATU but, as already said, the performance would be poor. For reasonable performance without something permanently mounted to the bodywork, personally, I'd go for a gutter or mag mount. Generally speaking, with any antenna regardless of frequency, the higher the better. JMO

 

[Trevor]

A compromise could be a rubber duck style antenna that you could fit where the current radio aerial is on the wing. It would only be effective for short range use (laning convoys should be fine). Maybe something like THIS

 

[sae70]

Lol, I've already got one of those Trev'





I was always very happy with my Siro it's an awesome twig to be fair with loads of range despite it being mounted on my back door.







I've even got it all ready to fit with a new blacked DV base and coax.


I've also got a nice big mag mount that it could go on, but it would just be no good on the roof when laning and really needs to go back where it was, which means a hole and I just want to try to avoid any holes this time round.


This is what I'm going with till I can find a solution that satisfies my desire for something covertly different. It's a short Springer that I had on my Suzuki's fitted to a new 3.5" 8 pole military spec mag mount from 4x4CB. I've popped it at the back as I'm thinking that if it gets caught and pulled off it'll just dangle over the back of the truck out of the way, but I hate it!!!! The way it dances and jigs about when the engines running like a mischievous toddlers that needs the toilet, awful bloody thing!

















I've looked at loads of twigs and combinations of mounts and read an awful lot about aerials and how they work and why they're made how they are all very interesting, but there seems to be nowt that'll tick all of my box's. Thought I'd found one from America that replaces the OE in wing radio aerial, but it's stiff with no flex so no good for off-roading! I do have a possibility with a window mounted one made by Midland, but need to do a bit more research into it. I just thought the covert bumper dipole twig seemed to fit the bill really.

Maybe I should design one myself and get it put into production

 

[Ben]

If you dont want to make any holes how about mounting it on the spare wheel/spare wheel mount?

Wouldn't be hard to fab up a suitable bracket.

 

[Doodle]

I've popped it at the back as I'm thinking that if it gets caught and pulled off it'll just dangle over the back of the truck out of the way, but I hate it!!!! The way it dances and jigs about when the engines running like a mischievous toddlers that needs the toilet, awful bloody thing!

I'd have thought the springer is to blame for that, the one on my friend's Disco TD5 does the same. I run a Sirio mag mount over the cargo area on the Amazon with a Megawatt 3k, and don't have any undue movement.

 

[Tractionman]

I went Ben`s route, and bolted on spare wheel mount, but still had to drill small hole in door beneath mount for cable entry (small dia. rg58 low loss), then I was on the cable limit as regards perfomance. Despite using four different make twigs of various lengths, and trying two different ground planes, I have come to the conclusion that nobody uses it much anymore, probably fine for convoy/green laning, but not general use - and the illegal am was so much better in it`s time..
BTW, sae70 how the hell did you get TX/RX on that solarcon/dial a match/rubber duck twig, mounted that low!

John

 

[CANEX]

I've just bought a load of CB stuff & I've got a few different mounts - gutter mount, wing mount, mirror mount, quick release & wing nut.
I don't know if any of them are of any use?

cheers
Chris