signal-to-noise

Anything that improves the signal-to-noise ratio is preferable. What's the point of receiving a 20 over signal in a 20 over noise? An s-2 signal in an s-1 noise is preferable. Industrial Communications Engineers, Indianapolis, Indiana makes a little device which allows you to transmit on one antenna and receive on another. It makes the switch automatically. It's worth building one.

Classic quarter-wave verticals are usually unbalanced and therefore are not necessarily reciprocal. I'm still trying to understand why. Unbalanced dipoles are often not reciprocal. In other words they sometimes get out better than they receive and vice-versa.

In any case, you should transmit on the antenna which is heard best and receive on the antenna that hears best regarding that signal-to-noise ratio.

I agree the verticals work well but it would never be my only antenna. Currently on 15 meters in the late afternoon I do best running the ground-mounted vertical with it's 13 radials and a vertical reflector in tandem with a horizontally polarized, full-wave loop. The cross-polarization reduces QSB considerably. (Come join us by the way at the Pacific Maritime Net, 21.412 at 21.30 utc.) However, it almost always ads a crackle to the speaker and that's not exterior noise.

If I had to choose just one, it would be, as I said: The full wave loop, upright, in either polarization, coax fed with only a choke. This is the best overall single-feed antenna I have found. Name some that are better.

And let me re-iterate. You can't prove it by my experience that noise is in the vertical polarization. I'm suggesting that verticals make their own noise and that the quietest ones are those whose fittings are neatly covered to reduce or eliminate leakage. The safest ones to use are those that employ some kind of shunt-feed, closed circuit feed point. (Although this doesn't eliminate the noise.)

It took me a long time to disprove the notion that: You can tell you have a good antenna when it hears the 'background noise on the band." I say again, very few hams have heard the 'background noise of the universe.' It takes hard work to lift the layers of man-made noise out of the picture.

Speaking to a retired antenna engineer who had worked on special projects out in the Pacific, I asked a really tough question to which I yet have had an answer. He said that they were listening to the 'background of the universe' on their ultra-sensitive receivers. I asked: How do you know?

This question has been answered but not often enough by hams.