Responses to questions from Scott WA9WFA:
> 1. I only have clear space for a K9AY on the lake side, down the hill
> from the house. This spot happens to be the farthest away from the power
> lines and poles, maybe 100' away from the drop pole. The hill is open to
> the North, East, and Southwest.
The primary issue with any small receive antenna is avoiding coupling to the
transmit antenna and/or other objects that can disrupt the pattern or be
large noise sources. It is relatively easy to try the antenna in a spot that
is convenient and see how it works. You might be surprised -- one of my own
installations was very close to the house and not too far from a power
distribution pole. Other than hearing my computer monitor a little too well,
it worked fine. If your handiest spot doesn't work, it sounds like you have
a good option for a better location. Hills and slopes won't have a large
effect, and the exact shape of the loop is not critical. It can be warped a
bit to get it installed on a hilside.
> 2. How do you think the receive signal strength or signal to noise ratio
> might compare with the inverted vee?
An inverted vee has only a little directivity, so an RX antenna with a
cardioid pattern like the K9AY Loop will be an advantage.
> 3. Can I expect similar spectacular performance on 80 meter cw as well?
Of course!
> 4. Why couldn't I just attach an Advanced Receiver Research preamplifier
> to the 160 meter inverted vee to achieve that 1 - 2 S-unit improvement?
> ARR is suggesting one could see 6-14 db improvement in signal to noise
> ratio. Thats 1-2 S-units.
A preamplifier will increase the level of signals AND noise, with no effect
whatsoever on S/N. The ambient noise on the low bands is what determines
S/N, not the gain or noise figure of the hardware. An RX antenna with
directivity is needed to help S/N.
> 5. I've been pondering a 160 meter antenna configuration that is sort of
> an inverted L, originating at the base of the tree at the bottom of the
> hill, a few feet away from the lake. ... I have no idea what to expect
> from such a configuration.
The ultimate rule is that any antenna will radiate, it's just a matter of
how well. For your tree-supported semi-random inv-L, simply do your best to
get the vertical portion as high as possible, and try to keep the horizontal
portion just as high. A drooping horizontal wire on an inv-L will be
functional, but less efficient than an well-elevated one. Be sure to install
enough radials!
73, Gary
K9AY
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