The rotated offset omni-directional antenna

This is an article I have wanted to publish for some time.

You know when you are driving down the road and you hear your FM radio fade in and out very quickly.
Those spots of faded low signal are called nulls.

In a mobile application, this is not really a problem.
If the signal is bad, you can just pull ahead or back a bit and the fade/null is gone.

In a non-mobile, or fixed base situation, this can be a real problem with the typical tower mounted omni-directional antenna.

Even a very high gain antenna, if installed in just the wrong spot (null wise), can show a very deep null on the signal you are trying to listen to.

One practical way to fix this, is to move the antenna 1/4wave forward, back, left, or right.
If a user wants to open many repeaters, or other fixed base contacts from a single location with an fixed omni, the odds are not in your favor that all the intended paths will work with minimal fade or nulls.



There is an easy solution, rotate your vertical omni.
Rotate an omni antenna....am I insane?
Well I may be insane , but there is a way to rotate the vertical omni, that works very well.
What one needs ,is a bent offset 1/4 wave or so at your lowest usable frequency for the omni.
I say lowest frequency because this could be a dual ,or tri-band (or more) omni-directional antenna.
So, if its a 2meter/70cm antenna , pick the lowest 2m freq you use, and make the offset 1/4wave of that frequency.
You do not have to be exact, and close will do.
For 2Meters it would be around 48cm or 19inches


By offset, I mean a piece of pipe bent so that it has two 90 degree bends, one forward, and one backward bend so that it resembles an L fused to an upside down L,( see ,and click on the above illustration).

You could also have a cross tree, or cross arm, and have an antenna on each arm.
One could bend or fabricate this many ways to achieve the same final result.
The main thing is that the antenna moves in a circle around the 1/4wave distance.
You would be amazed what repeaters, and stations, you can now access ,with this simple modification.
Or this method has the added bonus, to do the opposite, and null unwanted signals, or interference.

I have yet to try this with a horizontal antenna, and move in the vertical direction.
This would be a less practical application as most repeater signals are vertically polarized.
In theory however , it should work and likely has an application.

I did not invent this, or wish to take any credit for this method.
The rotated offset omni vertical, was showed to me by a true Ham Elmer: Dick Jones in Victoria B.C. over 20 years ago.
He was at that time VE7DHC, he is now VE7OZ.
The first time I saw this, was with his offset, and Ringo Ranger omni at the very top of his tower.
It sparked my love of antennas ,and all things related.
This wise man was the reason I became a Ham, and took the road I took.
To this day I owe a debt of gratitude to VE7OZ.

Give this offset method a try it, I did ,and have been looking up, and around ever since.