2006-10-19T02:33:00.000-07:00

MAKING OF WIFI CANTENNA

Overview

Antenna of Wave Guide in fact is not antenna, because it's not reinforcement but only instructing radiation of signal radio to be more. Effect of material refleksi and this focus is true finally yield a kind of reinforcement, but that is not especial issue desain of this antenna.
Desain of antenna truthfully really reckon maximum attainment effect of refleksi focus and for the shake of yielding reinforcement of radiation as issue the core important. Antenna Wave modification guide, ( for example with Cone or of Reflector) is an eksperiment to reach antenna that desain truthfully.

Materials:N-Female mount chassis konektor 4 nut tide and bolt, or according to requirement of copper cable 12 gauge sufficiently. 1 can, diameter the suggested is 3 inchi or 3 2 / 3 inchi.

Additional Materials:Cable ‘ pigtail’ ( with N-Male konektor) Card of Wireles able to be interfaced to ‘ pigtail’

Supply: Drill to make hole can, can change with axis and hammer. Solder nail.

CONSTRUCTION

First we selected a can with a diameter the suggested is 3 inchi or 3 2 / 3 inchi.. We calculated from this the value for 1/4Lg (a quarter of the standing wavelength inside the can), measured this far up from the bottom of the can and drilled a small pilot hole, then drilled the hole out large enough for a chassis mount N-type connector.

To the pin of the chassis mount N-type connector we soldered about 50 mm of 1.5 mm diameter stiff copper wire. This wire was then carefully cut to the value calculated for 1/4Lo. The edges of the N-type connector and the can around the hole were then abraded heavily with glass paper. The N-type connector assembly was then soldered in place to the can, on all four sides. It is important to get a good electrical connection between the N-type connector and the can.

Mounting

This antenna has a beamwidth of around 30 degrees and needs aiming. Also the polarisation is important, that is whether the driven element inside is pointing skywards (vertical) or sideways (horizontal) - this needs to match the antenna it is communicating with. We have been mounting them around a standard 25 mm television pole with a U-bolt attached to an adjustable mounting from a television antenna shop - this allows adjustment in the horizontal and vertical plane. This has then had a short piece of stainless steel tubing clamped in, attached to the can with glue and gaffer tape, or cable ties. None of these are a very good solution. This is one point needing more thought...

Download Netstumbler to check the signal from : http://www.netstumbler.com/downloads

List of tins so far found to be suitable :

Slimfast Double Chocolate - England - with plastic lid
The Simpsons Double choc cookies - England - with plastic lid
Douwe Egberts ground coffee - England - with plastic lid
Baby milk formula - England - with plastic lid
Furness Ginger Biscuits - Cornwall and England
Golden Jubilee Beer, Robert Cain Brewery - England
Nestlé Coffee Mate 500g - England - with plastic lid
J&B Rare whiskey tin - Portugal
Larios Gin - Spain
Stainless steel toilet brush holder from B&Q - very nice
Any large dog food

Read some theories in web following ( with a few of variations):
a. Example : http://www.turnpoint.net/wireless/cantennahowto.html
b. Can dimension: http://www.saunalahti.fi/elepal/antenna2calc.php
c. Guidance & modify Cone: http://http://www.saunalahti.fi/elepal/antenna2.html
d. High of Wave Guide: http://www.csgnetwork.com/antennawncalc.html
e. Detail Theory and example : http://flakey.info/antenna/waveguide
f. Theory and practice: http://www.lincomatic.com/wireless/index.html
g. Comparison theory: http://www.swisswireless.org/wlan_calc_en.html
h. Reference: http://www.king.igs.net/~karc/projects/antenna.htm
i. Other information: http://www.google.com/ or http://www.dogpile.com/
keyword: 2.4 antenna homebrew ghz

Source : take from some article on the internet

Cantenna