From: Ralph Mowery 
Reply-To: rmowery@ibm.net
P>  Anyways, there's the plans for what's called a Directional
> Discontinuity Ring Radiator. (DDRR)
> 
>> 
>  The 2M version stands only 1in. high, is 6in. in diameter, and
> is made from .25in tubing.
> 
>  The only problem is that the article doesn't mention anything
> about how it compares to other antennas. It only says that it
> will do 1.1:1 over the entire band when properly setup.
> 
The DDRR is a high Q antenna and the band width is small.  I doubt that
it would go a full mhz on 2 meters with a SWR the rig will load into
without adjusting the matching device.
If you intend to mount it up in the clear, you either have to have a
'ground plane' or you can sometimes get by by putting a ring the same
diameter under the DDRR radiating element at the proper spacing.
They are best used where you have a large metal area and can not put up
anything else.
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