At 06:26 PM 6/1/2007, Tom Rauch wrote:
>What's the latest thought on Yagi antennas? Is the old work
>by Lawson on Yagis still considered accurate so far as boom
>length, number of elements, and gain?
One might want to try using one of the optimizing programs out there
that use numerical modeling. 4nec2 is free, uses the NEC2 (or NEC4)
engine, and has an optimizer that works fairly well.
This is especially so if you are making different tradeoffs for
things like F/B, bandwidth, gain, and manufacturing
tolerances. There are some high gain designs that are exceedingly
sensitive to small changes in dimensions, and modeling will help you
avoid them.
Investing the few hundred bucks to get a copy of NEC4 is probably
worth it, if you are serious about modeling. It does much better on
cases of interest for hams (tapers, close to ground, angled connections)
Jim, W6RMK
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|