John,
You absolutely can make a hex beam yourself. Do a Google search and you'll
find great descriptions of how to build one and all the math about element
lengths.
73, Jim
places that sell only pi
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of John Miller
Sent: Wednesday, April 22, 2015 8:33 AM
To: [log in to unmask]
Subject: Re: Hex Beam and accessible rotor, part 1: the hex beam
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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