[bigcowhead]

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I am considering mounting a CB in my bike and would like to mount the antenna on the rear of the bike without making it look out of place. To this effect, I would like to mount it horizontallyout the back of the rearhatch opening. I am sure I can mount it no problem but am concered about the effectiveness of the antenna as it is mounted. I really want to only use it to talk with other vehicles I am sharing the road with and am not necessarily intersted in talking to another state.

What are your thoughts?

Everrett

 

[AZgl1800]

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Horizontal radiation is going to severely limit the range of the radio.

CB radios are already severely limited on range, simply because there is not enough metal on the bike to provide for an adequate "ground plane" to make the antenna itself efficient.

You should find some way to mount it vertical, and provide a good copper ground flexible cable strap (like for car hoods) from the mounting base to the bike's frame.

 

[William_86]

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a handed CB may work too. right?

 

[bigcowhead]

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What kind of take off angle do you think I would get? What kind of radiation lobe would I have off the antenna at that angle? I agree with a good ground with a copper cable.

Everrett

 

[AZgl1800]

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Typically, a metal rod or wire radiator will have a radiation pattern 90 degrees or broadside to the radiating element.

That said, there are thousands of horizontal antennas in this world that are being used on the CB bands.

The issue is that the radiation pattern needs to match that of the intended receiving end's radiation pattern.

If your buddy is horizontal, then you want to be horizontal.

But, the CB world is typically all vertical simply because of the mechanical considerations of having enough space to use a horizontal antenna.

A full length dipole would be 18 feet long. Your bike has to provide "1/2" the length of that dipole. Ergo, your antenna becomes a "vertical dipole" if you will providing you mount it vertically.

To get around the length problem, a "loading coil" is inserted in the middle of the vertical radiation element to approximate the "full length" of the antenna.

The problem is, 1/2 of the antenna is the bike. And that bike is not anywhere near 9 feet long.

It does has quite a bit of mass however, which helps to offset the loss of length. In order for the bike to provide the missing portion of the antenna, you must absolutely make sure that the ground side of the whip's connector is bonded to the bike's frame very solid.

Use braided copper flexible cable straps like those used on a car's hood. You can get those at Radio Shack or most auto parts stores.

 

[sle104]

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As a radio tech I agree with all the comments so far. Some new antennas being made are NO GROUND PLANE ANTENNAS. You can also use your AM/FM antenna with a splitter box for your CB however your range of transmit will only be about 2 miles. If you need more info PM me for part numbers and dealers

 

[EDDIE W]

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you really want a vertical antenna, one that has a ground plane built in, shakespeare make some nice marine antenna's for cb's

http://www.shakespeare-marine.com/antennas.asp?antenna=4051

 

[SB in SC]

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You'll get just as much range with a decent handheld unit, BCH. I've had good luck with my Midland 75-822 with the car adaptor.

Or, just go ahead and sell me that Tri-sport and buy you a 1500 with a CB built in!:cheeky1: