Linear Focus Parabolic WiFi Antenna (Part 2)

Simple Construction - Great Wifi Network Range Extender.

This antenna can be constructed in a couple of hours and some measuring, cutting, bending, and bolting metal. Use caution around the sharp edges. When finished, put it up and enjoy a very durable antenna that provides great signals.

The previous page discussed design concepts of the linear focus parabolic wifi antenna; now the spotlight goes to actual construction.

Assembly Procedure:

1. Mark all flats and flashing from edge to edge along their centerlines and across midpoints, both sides.
2. Mark dots on flat "A" along its centerline, at the 1," 18," and 35" points. Carefully drill holes at these points.
3. Abeam the hole at the middle of flat "A" drill holes on both sides, 1/2" inside of the edges. This results in a row of 3 across the flat at the 18" point.
4. Set flat "A" along its edge, and bend it to fit the parabolic template. Bend a little at a time, working along the length of the metal.

5. Mark flat "B" across the 15" point, beyond there by a distance equal to the focal distance on the template, and finally 3" beyond the focal distance mark.
6. Bend flat "B" to a 90 degree angle at the 15" line. Bend flat "B" 90 degrees in the opposite direction at the second mark (representing the focal distance). Flat "B" should now have a right angled "Z" shape.
7. Use the hacksaw to cut flat "B" at the third mark.

8. Mark across flat "B" at 7 1/2" from its long end (halfway to its first bend)
9. Clamp flat "A" onto the outside of flat "B" such that the three holes in the middle of "A" are on the centerline of "B" AND the middle hole in "A" is on the 7 1/2" mark on "B"
10. Make sure "A" and "B" are perfectly perpendicular and positioned as specified above, then drill through the existing holes an and into "B." "B" will then have three holes through its centerline that match the holes in "A." Set "B" aside during step 11.

Note how "A" and "B" are bolted together.

11. Clamp the flashing onto "A" along the inside of the curve, carefully along the centerlines, and drill through the existing holes near the ends of "A," making holes in the flashing. Insert the short screwsthrough the flashing and "A." Apply nuts and tighten securely.

YOU SHOULD NOW HAVE A PARABOLIC REFLECTOR WITHOUT A MOUNT

12. Carefully drill through the existing holes in the center of "A," making 3 vertical holes in the center of the flashing, 1/2" apart.
13. Place "B" against back of "A," with the Z bend extending under reflector and toward focal line. Line up the 3 holes and insert long screws through reflector, "A," and "B." Apply nuts and tighten securely.

YOU SHOULD NOW HAVE A PARABOLIC REFLECTOR that can accomodate a USB wifi adapter along the focal line.

For best performance, consider using a biquad feed. Other choices include using a colinear dipole, or using a 6" length of PVC to place a USB wifi adapter in front of the reflector. An alternative for systems not needing huge amounts of gain is the very simple - and smaller - linear parabolic on binarywolf.com. It enables extended range 802.11 connections better than the dipoles supplied with a lot of equipment.

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