OM3RKP

http://www.om3rkp.cq.sk/

WI-FI antenna (Constructions)

Look through the WI-FI antenna WI-FI band (2.45 GHz) is not so far from 2.3 GHz what is a radioamateur band 13 cm. An idea of G6KSN was the base how to build own WI-FI antenna.

I have compared three WI-FI antennas: original from AP, home made DL7KM (twin quad) and 10-element yagi loop. The last is the best. It's not a problem to copy signal from AP in distance 4.5 km!

The building is relative easy (easier than it looks). Things needed: PCB, N-type connector, piece of thin 50 ohm coax, some Cu wire with 1,5 mm diameter, Cu tube 8 – 12 mm, knife, soldering iron, etc.

An inspiration for building this antenna is an article http://www.paramowifix.net/antenas/loop_uda_yagi/. This looks a little bit too long. I choose smaller version with 10 elements. Total lenght of mine antenna does not exceed 30 cm.

Here is an output from programm:
An output from G6KSN programm

Reflector was made from a piece of PCB. Diameter of the ring is near the same like diameter od CD. Drill a hole for N-type connector. With a soldering iron connect to the reflector boom (Cu tube).

Make the marks on tube in the element positions. Elements are made from Cu wire. Each ring was made so: cut an exact length of Cu wire for element (for example 135 mm). Wind it on a tube with a little bit smaller diameter how the ring should have.

Design of WI-FI antenna

Hold the elements in a position and connect them to the boom with a soldering iron. The driven element is cutted in the half. There is connected a piece of coaxial cable (RG-58, semirigit, etc.). The other end is going to the N-type connector. Leads should be short as possible!

Mechanical construction:

A program Loop Yagi CALC You could obtain .: HERE :.. Antenna was sucesfully tested and used on WI-FI band. But there is a premise that it should work good also on radioamateur bands. Be careful with a polarizations of signal, especially on WI-FI (horizontal, vertical, mix). Setting-up for best signal needs few minutes.