Johan Van de Velde wrote:
>
> What a surprise
> Its commonly know that gain versus boomlength is fixed
> You ought to read DL6WU and DJ9BV's paper on this.
>
> each doubling of boomlength gives you just over 2 db extra gain.
>
> It has been proved in europe with different experiments.. expecially on VHF
> UHF antennas where is is easier
> to perform such tests..
>
> I still laugh at the claims from certain manufactures..
>
>
> All the rest is pure imagination of manufacturers..
>
> Johan
> ON4ANT
>
I was discussing this exact subject with Art just before he left
Cushcraft and he agreed that some manufactures grossly overestimate
gain figures. They are basing gain figures on some theoretical
isotropic point that has zilch in common with real world
transmission. Gain over dipole at the same height and terrain is a
relevant yardstick. Art and I were specifically discussing short
boom antennas such as a 14 ft boom tribander. He agreed that real
world 20 meter gain on this antenna was probably much closer to 4.8
- 5.0 db.
de ... N1MSV (gary - on the cape cod salt marsh)
Gareth http://www.capecod.net/~gareth
.....at the dawn of the New Age of Man,
they will abide with us.
Their glory and fire will burn like
sparks among the stubble!
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