Area 51 for Antenna Modelers & Builders (See Post #1)

[stampeder]

This thread has been created strictly for Antenna Modelers and Builders who like to live not just on the leading edge but on the bleeding edge of antenna research and development.

Area 51 is for posting and discussion of any computer model of any experimental antenna by Antenna Modelers and Builders

Area 51 is not for casual builders or newcomers to ask questions or look for useable home antennas. Participants here are expected to fairly well "know their stuff".

If an antenna design is shown to be worthwhile for general public consumption we will move it out of Area 51 into the main Antenna Research & Development Forum.

Just remember what the ancient map makers wrote when they had no further info to illustrate: "Beyond here be dragons!"

[300ohm]

Sounds good. Also for beginning modeling questions, there is still this thread :

http://www.digitalhome.ca/forum/showthread.php?t=83772

which is also not for casual builders or to look for useable home antennas.

[stampeder]

Can't wait to see some of those really whacked NEC files you guys keep hidden away...

[firimari]

I'm working on a fully-paramerterised (i.e. symbols all over the place) second-generation koch curve single diamond one right now. So far it's got about a 9 dB gain, but the SWR is crappy, so I'm adding more parameters to the optimiser in 4nec2.

[stampeder]

Great - I'm suggesting a model naming convention to prevent confusion if/when discussions overlap:

When you post a new model, name it X-[post number here] i.e. if your first post of it is #789 the model would thus be the X-789.

Does that sound reasonable?

[300ohm]

Does that sound reasonable?

Sounds as good as any. Autofils and I tried to come up with some sort of logical naming scheme for the GHs and just couldnt do it. Almost gives me a headache thinking about it, heh.

[stampeder]

http://www.digitalhome.ca/forum/showthread.php?t=106046

[Xauto]

I just have to add my in put. For the newcomer. I would have him build X-032 (area 51). I just came from a friends and that is what we made in about 1hr. One needs a spine that is over 30". We used a 4'by 1/2" square stick and 1/4" dowel and 7' of 14 gauge steel wire. starting 1" down from the top of the square stick put in a nail for the top of the upper diamond. From there down 4 7/32" drilled a hole for the first spreader( 8 7/16" of 1/4 dowel). Then 7 13/32" drill 1/4" hole for the next spreader ( 6 3/8" of 1/4 dowel ). Now down 2 19/32 a 1/4" hole for the feed point spreader (2" of 1/4" dowel note that there needs to be two screws in it to attach the 75 to 300 balun) you are half way just add two more spreaders and to mirror the top two spreads and add the wire in the diamand shapes. This with a reflector will give you a 11dBi antenna.

[firimari]

I would love to see photos, it was really just a reverse-engineering of a picture, so it's nowhere near original work. However, since I didn't have an original to go from, having experimental data would be a great proof of concept.

[300ohm]

Yeah, the X-032 does look like a very simple to build antenna with just one piece of wire. It has a very wide beam pattern (similar to the C2 and wifi bi-quad/double bi-quad), which makes it easy to aim. With a mesh reflector, its gain is from 11 to 13 dbi. It would be a good suburban uhf antenna, as its use in Europe shows. (but it is different than the Faccaro P-54) I think it should be moved out of the experimental area and into the regular thread, if some easy directions are posted with it. (I find it difficult to visualize the above directions Xauto, heh. Maybe some construction pictures to go with each step ?)

[Xauto]

I will try to demonstrate the building of X-032. I will build and take pic.s, because the one from the weekend is 200 miles away.

[Xauto]

Build instructions for the driven element of X-032.

If your rabbit ears do not work, try this build.

Materials:
1 1/8" x 1 1/8" x 3' wooden post.
1/2" wooden dowel, 31" worth (I suggest going with 3 feet).
Two nails.
Two screws.
7' of 14 gauge copper wire (I used 2 pieces, both 3 1/2' in length. Joints were under the nails).

Instructions:
1) Start by marking the post at 5 7/32", 12 5/8", 17 3/4" and 25 5/32".
2) Drill 1/2" holes at these locations in the center of the post.
3) Rotate the post 90 degrees.
4) Place your nail on this side at 1" and 29 3/8" (Do not drive all the way in).
5) Place two screws at 15 3/16".
6) From the 1/2" dowel, cut two pieces 8 7/16" in length, as well as two pieces 6 3/8". (These will be used as spreaders)
7) On all four dowels, cut a notch with a saw into the end of each dowel for the wire to set into.
8) Install the 8 7/16" length dowels into the holes that you made at 5 7/32" and 25 5/32". Then, install the 6 3/8" dowels into the two remaining holes.
9) Install the 14 gauge wire onto the frame as shown in the provided picture. (Note that at crossing points, one wire is on one side of the post, and one wire is on the other)



Edit: 1/2" pvc (spine) and 1/4" (spreaders) driveway markers would make better frame materials, but this mornings dumpster dive did not yield this.

[stampeder]

Xauto, that's a great photo for explaining how to build the frame and loom the wire. The over-under for separation is clever.

300ohm and firimari: I'm wondering if X-034 supercedes X-032 or would it be a variant?

All: is there any point to a double bay X-032 or X-034?

[300ohm]

300ohm and firimari: I'm wondering if X-034 supercedes X-032 or would it be a variant?

The X-034 just has a simple 2X4 mesh reflector rather than the rods in the X-032.

A double bay version hasnt been done, but I believe that would narrow the very nice round front bubble pattern on it, one of its main advantages for suburban use. Its gain and pattern is very similar to a C2, but a heck of a lot easier for the home builder to make. A double bay mesh version should have from 15 to 15.5 dbi raw gain, which is still less than any DBGH.

The bi-quad wifi antenna, similar looking, is used in a lot of configurations as a parabola driver. Ive got mine finished, but still need to put a cable on it. (I hate to scrap this little wifi antenna I have, heh)

Xauto, your directions make a lot more sense to me now, heh.

[300ohm]

Edit: 1/2" pvc (spine) and 1/4" (spreaders) driveway markers would make better frame materials, but this mornings dumpster dive did not yield this.

Also, Lowes and Home Depot have rectangular about 3/4" by 1 1/2" plastic lattice edging that could be substituted for the wood.