I'd like to ask you a riddle.
I bought this antenna on eBay and it is sensed to
work in the 2.4GHz band (wifi). But as its performance
was really poor, I dismantled it.
is based on the so-called
, like the one I found on the net
I mesured the different elements:
(2 tubes + empty space): 90.8mm
sections: 1mm washer
space between tubes: 34mm
outer tube diam: 28,4mm (no dielectric
filled, air only)
inner tube diam: ~28mm
coax diameter: 3.8mm
the oscillation starts from the bottom tube. But
what parts do radiate: the tubes or the inner coax?
Have you found its fundamental frequency? I'm
longing for your answers...
PS: does anybody know how to model this kind
of antenna in 4nec2? Especially for the tube and
coax. I'm quite newbie at this software.