[DX] FS: Brand New Tennadyne T3.20M 20m Monobander

[Jan Robbins]

Bill Tippett wrote:

> N0JR wrote:
> > 3 driven elements optimally spaced at 9' on an 18' boom, gain in 
> excess of
> 8dbd.
>
>         Caveat emptor.  I don't believe Tennadyne's claim below of
> 8.5 dBd (or 10.6 dBi) for an 18' boom on 20 meters.  Like most
> things in life there are no free lunches (or magic) in antennas.
> Gain is a direct function of boom length.  According to NEC
> models, you need boom length of about 40' to achieve >8 dBd (or
> 10.1 dBi) on 20m.  Claims like this are why ARRL doesn't accept
> antenna advertising without specific reference to NEC modeling.
> If Tennadyne is touting this sort of performance, I would be
> highly suspicious of anything else they claim.  Remember the
> Gotham vertical ads years ago?  Caveat emptor!
>
>                                                 73,  Bill  W4ZV
>
> http://www.tennadyne.com/new_models.htm
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>
There are no free lunches.  There are a lot of empty heads who know 
nothing of driven arrays, however.