I'm talking about 350 numbers averaged, for example covering the 20 meter band
- not averaging two numbers like 10 and 20 dB and I'm suggesting that because
an antenna can have in excess of 60 dB of front to back at a few frequencies
that the F/R number is more important. Unless you are a direction finding
person or trying to null some particular source of QRM, front to rear is a
better number to look at. The thing to avoid is for one manufacturer to claim
35 dB of F/B when in reality that occurs at 14.287 and there is no place in the
band where Front to Rear is even 20 dB while another antenna is overlooked
because it is shown to have 18-20 dB of F/R across the band.
Stan
Sent from my iPad
> On Dec 11, 2014, at 4:52 AM, Steve Hunt <steve@karinya.net> wrote:
>
> I agree that Free Space figures are probably the least ambiguous; but I'm not
> convinced that "averages" are very helpful!
>
> What do we mean by "average"? What's the average of two F/B ratios, one of
> 10dB and one of 20dB?
>
> [The average of 10dBW and 20dBW is 17.4dBW]
>
> A "not worse than" figure across the bandwidth may be more meaningful.
>
> Steve G3TXQ
>
>
>> On 11/12/2014 10:30, Stan Stockton wrote:
>> If every antenna were compared to every other antenna in terms of free space
>> gain and all in the same unit of measure (say dBI) and if the numbers for
>> gain F/B, F/R, etc were shown as average across the band then there are no
>> additional questions to ask to determine which antenna is better or best.
>
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