Walter:

Well, it all depends... (Bet that was a whole lot of help...)
Personally, nearly all of my antennas are for transmission as well as
receiving, and I can tell you that what most people call a "Sky Wire Loop"
has been pretty effective for me. I am located at an elevation of a
whopping 180 feet above sea level, approximately 2 miles from the ocean.
My location is about 119.5 degrees north latitude and 155 degrees west
longitude on the Big Island of Hawaii, the southernmost island in the
island chain. From here, just about everything you'd normally hear is
considered DX.

I've had a 600 to 700 loop up, supported by local and brittle trees
(albesia) that started with an average installed height of about 30 feet,
and eventually got down below 20 feet average height before it got pulled
down. At the current time, I've got poles in place to install about a
1000 foot loop nearly 40 feet high, but am waiting for hurricane jimene to
pass the big island before I put up the big loop. We expect the hurricane
to pass us Monday morning without landfall (if all goes well), and I'll
get the wire loop back up once it passes....

I got decent results with the 600+ foot loop on all bands except 160m, and
it may have not been all that effective down there anyway, given my
location. From here, nearly any contact (except those few within 200
miles) is DX. No short skip from here, unless it is in excess of 2300
miles....

I've been favorably impressed with the performance of the 600+ plus loop
both in receive and transmit, so much so that I was willing to spend
nearly $500 to put up the 1000 foot loop, not including the cost of the
boom truck to raise the poles to support the new loop. If you're so
lucky as to have some tall trees, so much the better, as the actual wire
costs are pretty inexpensive. I use 12 gauge stranded, insulated wire and
have had no problems with wire loops (in several locations) for nearly ten
years using typical THHN type stranded wire. You may get away with a
smaller gauge wire if you aren't using trees for supports, (but I will
still be using 12 Ga. for my pole supported loop... Habits die hard
sometimes in the Ham Radio world.) You could even use bare wire, but I
prefer insulated wire because if I get in contact with a tree or other
support, I don't have to worry much...

Well, this got a bunch longer than I intended, but the bottom line is: If
you are wondering about how effective a decent sized loop can be, put one
up and find out. Typically, you won't be disappointed. Horizontally
oriented loops don't seem to get much of the local interference like
vertical whips do, and they are essentially omnidirectional, with some
gain depending upon the number of wavelengths for your band of interest.
There are definitely times that the loop outperforms even a decent beam,
and others where the beam really shines and loop takes second place, but
if you don't have a good tower with a rotatable tower for the bands you
are interested in, a large, horizontal loop can't be a bad thing....

Good luck and Good Listening!

Thanks
--Rick AH7H

Walter wrote:

Should I run a Sky-wire loop?

I currently have a dipole hung by two trees about 30 feet off the
ground.

I would replace the dipole and run the Skywire loop off the same
trees, along with two more trees at the same height as the current
dipole.

This antenna would only be used for receiving, and never for
transmitting, the same for the dipole.

My question is, does anybody think it will make enough of a difference
over the dipole to warrant running it?

I would also like to know what your views are on "grounding" either
my current dipole, or the Sky-wire.

Currently, I have the coax center wire soldered onto one end of the
dipole, and the braid soldered onto the other end. I was told that I
should also ground the braid before it comes into the house and into
the radio.

I do have a ground wire attached to GND screw on the back of the
radio, going outside to a piece of copper pipe pounded into the
ground. Is this enough, or do I need to also ground the braid, and if
so, how? Will grounding help my reception, or decrease the noise on
the line?

Thanks.