Quote:
Originally Posted by btrayfors  s/v Illusion,
Sorry, your post came while I was composing mine.
No, it's NOT true that an inverted vee is the most effective. In fact, the opposite is true if we're talking about long-distance communications.
The reason is simple, and can be found in the ARRL or any antenna handbook:
1. a vertical dipole, rigged close to the ground, puts out nearly all its power VERY CLOSE TO THE HORIZON....it has a very low angle of radiation...and that's precisely where you want it for DX;
2. an inverted vee has a much higher angle of radiation, better for short hops but not for DX.
Over the past 40 years of use I've proven this over and over in actual use, not just theory. And, more recently, the big DX-peditions have discovered vertical dipole antennas, and often prefer them to yagis!
The limitation on a small sailboat, of course, is the amount of hoist. Usually, a 20meter dipole (about 32' long when trimmed) is about all you can handle vertically. So, for the lower bands you're left with some other configuration...an inverted vee or an "L" or traps or....
Bill |
I don't think you'll find where I said an inverted V is the most effective...
What I said was in the post above - sorry if I wasn't clear.
If you've been a ham as long as me, I think you'll agree there is no such thing as a generalization about any one antenna which is always true - in this case, the vertical compared with a sloper for example in terms of low angle radiation over a good ground.
Not my intent to argue the minutia but with boat antennas, all benefit equally from the perfectly-conducting "ground" and it's hard to say any one is that much better. I've seen too numerous times the unfortunate result when someone tried to makeshift a specific design which really didn't "fit" their boat and in so doing, caused damage or created a dangerous situation.
What I try to suggest to people contemplating erecting an HF antenna is to make sure you have the best counterpoise practical, good cables, good connections and an antenna that doesn't interfere with access, movement or rigging and if possible, not capacitively coupled to anythign else although that too can often be ignored.
K1VSK
playing with antennas since 1960
p.s. never trade my monoband yagis for a vertical for any $$$