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Its actually just a ground plane vertical.. Its the standard design for elevated quarter-wave verticals... If you find matching to coax to be a problem, change the angle of the 4 sloping elements (the ones connected to the braid) with respect to the vertical element and this will adjust the feed point impedance.

73 and good luck!

Mo-Go
 

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Would it be better for skip doing this vertical or horizontal?

thanks

At 27 Mhz signals tumble and change polarization in the ionosphere so it makes not one bit of difference the polarization of the wave for "skip". Its a different story for ground wave. If you are working people ground wave (in other words, locals), the polarization can matter significantly...

The antenna described needs to be oriented vertically. You can get weird interactions with the ground due to symmetry (or lack there of) if you tried to mount it horizontally.

You can use a traditional 1/2 wave dipole, which is light years more simple than the ground plane if your goal is "skip land" but just realize that an AM CB running a 5 watts carrier is going to be at a serious disadvantage working skip. Not to say it wont happen, but we are in the midst of a very poor solar cycle so the sun isn't going to help you much.. You would be much better off using SSB... thats more info that you asked for, but I think its pertinent.

Whatever you do, put it high and in the clear...that almost always helps..

Pinhead is 100% correct - most CB guys are running vertical..

73,

Mo-Go
 

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If you are going to use a dipole make sure you have a good SWR meter so you don't destroy your radio. Exact measurements are extremely important when building a dipole and keeping the SWR within tolerable range.

A buddy and myself built one just a few months ago and it was tough to get the SWR to where we felt comfortable using it with his SSB. We ended up taking it down because of the risk to the radio.
 

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If you are going to use a dipole make sure you have a good SWR meter so you don't destroy your radio. Exact measurements are extremely important when building a dipole and keeping the SWR within tolerable range.
I certainly don't disagree with this but just make your calculations (468/freq (MHz)), measure twice, cut once and look at it on a meter... There is no reason to be afraid of it... SWR up to 1.3:1 rarely create problems for modern power transistors (Which is very easy to attain assuming you aren't negligent!) and at 12W for SSB (which has a reasonable duty cycle due to the suppressed carrier) isnt going to generate much heat or voltage.. the real killer of power transistors is open or short circuits... That will generally kill a PA deck without SWR foldback protection faster than antenna mismatch ever will (exceptions apply like trying to feed an off center fed dipole directly and without an impedance matching device - for ease of match to the coax, it needs to be a true 1/2 wave dipole).

Good luck and 73,

Mo-Go
 

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http://www.livecbradio.com/home-made-cb-radio-antenna.htm

I plan on pulling this up a tree possibly 30 ft. Is there a possibility of talking skip on this type of antenna?

They call this a dipole but it has 4 hanging verticals.
It's not a dipole, it's a 1/4 wave over a ground plane. The vertical conductor is directly excited, the horizontal ones are connected to the shield on the feedline act as a reflector ('ground plane'). The reflection takes the place of the missing half of the dipole.

It's a fair antenna; not great, just 'OK'. It's vertical beam width is a bit broad compared to 1/2 wave and 5/8 wave verticals, and it's radiation angle is a bit high. 30 feet is high enough, but being in amongst the leaves on the tree won't help it's radiation pattern any.

If atmospheric conditions are absolutely perfect, you could talk skip with 4 Watts into a quarter wave vertical, but it's not something you can count on happening often.

Having said all that, I say make it anyway. It'll cost almost nothing, it'll be a good educational experience, and it's kinda fun to talk on something you made yourself even if it is just across town.
 
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