At 07:52 AM 2/4/01 -0500, Tom Rauch wrote:
>> What are the gain bandwidth and SWR bandwidth characteristics that go
>> with that very high F/B? I bet there's no free lunch.
>>
>> 73, Pete N4ZR
>> Contesting is!
>
>There never is Pete.
>
>Actually the gain is quite good, because the real null is
>intentionally moved up at a useful wave angle. It is only when the
>null is placed directly off the back in a small endfire array that gain
>is less than optimal.
>
>Extremely high F/R ratios or very deep null depths do NOT
>necessarily run contrary to maximum gain.
No, but I wonder how they relate to F/R bandwidth, gain bandwidth and SWR
bandwidth. A lot of work has been done to get all three of these in
reasonable balance, and I don't recall any 3-element solutions that have
actually yielded 50-dB F/R over anything like an entire band, much less in
combination with acceptable SWR bandwidth and a fairly flat gain curve in
the range expected for such antennas.
73, Pete N4ZR
Contesting is!
The World Contest Station Database
is waiting for your input at
http://www.qsl.net/n4zr
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