SO I bought this antenna: http://www.amazon.com/gp/r.html?R=1JQU7FC84BE1O&C=3T5MUR8F9569O&H=WXZ2N2...
Also bought a external antenna "kit" for adding an external antenna to my Netgear WNDR3400 N600 dual band router. Did the drilling and successfully hooked up the antenna mod kit to one of the 2.4ghz posts inside the router. Hooked up this antenna and I get no appreciable improvement in range. I'm trying to pull in an xfinitywifi signal that I can see on my laptop, but do not have a good enough signal. I'm looking to connect to it with dd-wrt and repeat it so I can get access with my laptop by connecting to the virtual interface on the router. I was able to see the signal at times with the router, but it was hit or miss, just too far from the source. But adding this antenna has done nothing. Now granted, I just hooked it up inside, and put the antenna standing up in an open area of my living room, but thought for sure it would pull it some more wifi signals as I live in a pretty tight community with lots of homes nearby. What could I be doing wrong?
This antenna type is a dipole and has a design gain of about 3 dB not 12. the gain stated is a flat out lie. You need a Yagi directional antenna to get between 8 and 10 dB. To get the 12 dB gain stated you'll need a parabolic dish or a large (long) Yagi. You are doing nothing wrong except buying from crooks. If you are using 2 receivers like some of the N type wi-fi, you'll need 2 of these antenas to get the high speed data rates but with one, you should see the signal level increases if pointed at the source. Best of luck!
Thank you for the reply. I actually sent that omni antenna back (before your post, which it looks like I would've anyway) and went with a TP-Link 14dBi directional. It seems to be pulling in some more signals, but I'm still not able to get the one I want. I find it odd that my laptop can see and log onto the signal (which is a public wifi hotspot, xfinitywifi). The laptop has a standard internal wifi card with no antenna or anything! The laptop can see it almost anywhere in the house (with low signal strength), but the router cannot. It pulls in a lot of local wifi networks (I live in a pretty tight community) but nothing too far out, with or without the antenna. With the new directional antenna I was able to get the hotspot siganl once for a short time, but since haven't been able to latch on again. When I do a site survey it shows up maybe 1 in 10 times I check. Does the router, and dd-wrt, have any settings I can adjust? Again, it's a WNDR3400 that has repeater functionality in the latest dd-wrt build.