> TVI perspective. I am a little skeptical of this claim.
So am I, to the point where I think it is largely nonsense.
I recall a big article about how to lower EMI in consumer
devices by installing an Inverted V dipole with the apex
down.
The basis for this nonsense is the true statement the local
electric field is weaker when the dipole ends are up in the
air. The flaw in that concept is most problems are probably
not from the electric field, but rather from the magnetic
effects and that as little as 1/8th WL away a stronger
electric field becomes a stronger magnetic field, and vice
versa.
I think this misunderstanding comes from not understanding
how consumer devices react to nearfield problems, and they
think because since we often define problems in terms of
electric field intensity it somehow means that is the field
causing the problem. They probably also miss the fact that
1/8th wl away, everything can invert anyway.
A few things at that site seem to be unclear, such as the
statements about gain of dipoles and Yagis. I don't know
what he is trying to say when he says a 2 element antenna
with 4dBd gain has less gain than his compact antenna with
2dB gain. It is not clear to me what he is saying.
So we have some bent folded dipoles. Good enough. Other than
the impedance change, that's the same as any other dipole
the same shape and size. Less gain and efficiency than a
full size antenna, but hey...if that's all you can do.....
73 Tom
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|