Posts Tagged ‘plastic tube’

Omnidirecional WIFI Antenna 6dbi

Thursday, September 6th, 2007


This one is very interesting design. I was used something VERY similar before time and all that I remember is, that it defiantly WORK fine, but it is pain to tune this.

All pictures are from this page : http://www.guw.cl/sitio/index.php?option=com_content&task=view&id=78&Itemid=36

This antenna is combination from usual J Pole antenna and Franklin array antenna /AMOS antenna only onmidirectional /.

Gain of this omni antenna is around 6dbi, but you may add more by adding more sections. Double the sections to add 3dbis.

omni-6.jpg

Dimensions :

omni6-dim.jpg

And feeding point and tune stub :

omni6-sec1.jpg

Some suggestions :

First CHECK dimensions of Your antenna.

Second : Matching to the feed-line is archived by sliding the connection of the feedline back and forth along the stub until an SWR as close as possible to 1:1 is obtained.

Third : Try to add quarter-wave ground plane.

Four : You can bend the half wave section to a half circle to be able to use small diameter of plastic tube :

close_2j.jpg

http://en.wikipedia.org/wiki/Slim_Jim_%28antenna%29

Some more pictures :

omni antennaomni11.jpg