2.4GHz 20dbi RP-SMA Male Wireless WLAN Booster Omni Antenna Booster

Just ordered a couple of these.  Does anyone have any experience?  It just seems too good to be true that you can get the same gain as many of the dish antennas with a glorified rubber ducky.  That said, even if it is only 10-15dbi, it should more than do what I need done.

Anyone else have any insights?

KE7YKP

I'm highly skeptical. 

If it does work, you'll need to be sure it's precisely aligned vertically.  It's got to have a narrow vertical pattern if it's got that much gain. 

There's probably some basic physical limitation that an omni antenna of x wavelengths can only have a gain of f(x). 

It's 15 inches long, which is 3 wavelengths.  As a very crude estimate, assume that's like 6 dipoles stacked up on top of each other.  A dipole is roughly 2 dbi.   6x power is 8 db, giving around 10 dbi.  Real antennas are probably less efficient.

As I said, that's definitely a SWAG guess.  I'm not an antenna expert.

Well I received my antennas, and they look pretty cheap.  What do you expect for $6 and change.

I don't know enough to comment particularly authoritatively, but I thought some of you might have an opinion or insight into what is going on with this antenna.

The antenna is made from hard plastic like ABS or something rather than the hard rubber one would expect.  The gray cover snaps into place with plastic connectors.  There is a simple dab of glue at the tip to connect it there.  The detents in the joint engage nicely, and should hold reasonably securely at vertical, 45 or 90.  The only label on the whole thing is a small sticker that says 2.4g inside the joint.

From there I will let the photography speak.

Here are some photos:

I have some 9dbi Linksys antennas, and this is about the same length.  My guess is it is probably closer in performance to those, though you never know.  Perhaps there is some magic sprinkled in there I have missed :)

KE7YKP

Well, it won't have 20 dBi now, you let the magic smoke out when you opened the sealed cover.

Thanks for the picture.  I don't think I've seen a 2.4 GHz antenna in the raw like that before.