Now, being on a budget, what *I* do is save this message and in my spare
time, if any, I go out and see if I can build one myself that works. It
sounds like a fun project to make. I think about all my antennas at this
point are built or rebuilds where someone gave me something that either
worked or didn't and I go from replacing hardware and cleaning up
connections, to complete clean ups and complete rebuilds sometimes even
fabricating parts if needed.
----- Original Message -----
From: "Jim Kutsch, KY2D" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, April 22, 2015 8:09 AM
Subject: Hex Beam and accessible rotor, part 1: the hex beam
> Howard and all,
> In answer to your question about my hex beam and to add to the accessible
> rotor discussion, I'll explain my setup. This will be in three parts. Part
> 1
> is about the hex beam itself. Part 2 will describe the mast I used and how
> I
> mounted it without guys. Finally, part 3 will describe the modifications I
> made to a Ham IV rotor control to allow accessibility and also automated
> control from the PC with an interface to ACLog. Here's part 1: the hex
> beam:
>
>
> The Hex Beam that I bought is the K4KIO Hex Beam. Of the three major
> brands,
> this is the intermediate price point. It comes in kit form in two boxes.
> Everything is pre-cut, pre-measured, and connectorized.
> As has been described here before by others, the hex beam looks like an
> umbrella turned inside out. It consists of a base plate with about a 4
> foot
> vertical square piece of metal rising up from the center of the base. This
> vertical piece becomes the center insulator for the driven elements
> described later. Around the base plate are six fiberglass rods that are
> called spreaders. Ropes are used to run from the end of each spreader to
> the
> top of the vertical piece. These bend the fiberglass rods upward such that
> the ends of the rods are at the same height as the top of the vertical
> piece. Essentially, it makes a bowl shape with the vertical piece in the
> center.
>
> The simplest form of a hex beam is a single band hex beam. The antenna
> itself is a two element beam. The driven element is a dipole made of two
> pieces of wire with the center attached to the vertical piece in the
> center
> of the hex beam. The driven element wires come out to the ends of two
> spreaders then bend back towards the ends of the next two spreaders.
> Essentially, when viewed from above, the driven element looks like the
> print
> letter W. The reflector is another piece of wire that curves around the
> back of the beam using the remaining spreaders to support it. When viewed
> from above, the reflector looks like the print letter C. The driven
> element
> and reflector are made up of one continuous piece of wire and rope in
> combination. It starts with a wire that is half the length of the driven
> element, connected to a piece of insulating rope, then that is connected
> to
> another wire that is the length of the reflector, then that is connected
> to
> another insulating rope, then connected to a wire that is the second half
> of
> the driven element. By constructing these wire/rope combinations first,
> the
> antenna is put together by attaching the end of the wire (which is the
> center of the driven element) to the center vertical, bringing it out to
> the
> end of one spreader, then bringing it around all of the remaining
> spreaders,
> then bringing it back to attach on the other side of the vertical piece.
> The
> K4KIO Hex Beam has pre-installed wire clips on each spreader so you just
> need to thread the wire/rope around through all of the clips.
>
> The spreaders have to be long enough to support the elements for the
> lowest
> band you want to operate. For 20 meters, it's about 21 feet in diameter.
> The
> 20 meter elements are mounted at the ends of the spreaders where the
> circumference is greatest. Additional bands can be added by using shorter
> versions of the wire, rope, wire, rope, wire combination and mounting them
> to the fiberglass spreaders at lower points where the circumference is
> smaller. The K4KIO Hex Beams can have up to 6 bands. I ordered mine with
> all
> bands: 20, 17,15, 12, 10, and 6 meters. Again, all of the wire clips were
> pre-mounted at the appropriate locations on the spreaders.
>
> If you want to read a lot about the construction and theory of the hex
> beam,
> there are great articles in the "hex ed" section of the K4KIIO website at
> http://www.k4kio.com/
>
> Leo, K4KIO does a great job of sending you all you need in kit form. He
> builds all of the elements, attaches the tie points on the spreaders for
> the
> elements, and tests everything before shipping it. It is possible to
> assemble the kit without sight. I'm totally blind and built mine once I
> had
> someone read the labels to know which element was which but thinking about
> it, I could have just unwound the wire and arranged the wires longest to
> shortest and figured it out without help.
>
> I built it with the base lying flat on the driveway. Then I put it at
> about
> 4 feet above ground sitting on a pipe put through the umbrella hole in our
> patio table. That way the dogs wouldn't run through it and get snagged on
> the wires. But, I couldn't wait to try it so connected it to the rig from
> the patio table. Due to a late start and a very bad winter here in NJ, I
> ended up using it that way for almost 5 months. It worked better than my
> Carolina Windom even at only 4 feet but the coax got caught in the snow
> thrower and I had to cut it out and buy new coax. Last Thursday, I put it
> up
> on a mast. Now it's at about 20 feet. Since Thursday, I have worked 6 new
> countries and I'm only running 100 Watts from an Elecraft KX3 with the
> KXPA100 amp.
>
> The hex beam is not very narrow so you don't have to aim it accurately. It
> does have a really good front to back ratio and the noise floor is much
> lower than with my Carolina Windham.
>
> I'll describe the mast and mounting in a subsequent post Overall, I'm very
> pleased. I had a 3 element triband TA33 Junior and a full TA33 in the past
> at a different QTH and this hex beam seems comparable. In addition, it has
> 17, 12, and 6 meters which I didn't have with the TA33.
>
> 73, Jim
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