Hi everyone.

I want to make a  modification, adding an external antennas for this little router. I know nothing about wifi wavelengths, etc. So i need help from you.
I want to buy a wifi pigtail connectors and 5dBi antennas.
So my question is, can i solder the pigtail wires on green circle, and can i need to cut the existing antenna on PCB on yellow line?

Nobody ?????????
I really need to make this mod.

I cut the antenna  and works fine!

I have *some* radio experience and understand a basic amount about microwave radio frequencies, but I'm not an expert, so take this advice accordingly...

No, don't cut the traces where you indicate and don't attach the antenna at the resistors you circled.  Instead, de-solder the white surface mount capacitors (circled in blue below) near those resistors and solder the center coax antenna leads to the capacitors' pads nearest the radio (indicated by green lines below).  Connect the shield (braided conductor) to the gold test point pads nearby (blue lines below).

As a reference, below is a picture of my WNR2000 which originally had 3 (only 2 connected) antennas on the PCB.  Both connected antennas also had tiny connectors for external antennas already installed.  Notice that the connector on the left is between the radio and the capacitor C219 (which I have removed, probably not necessary since I think the RF connector disconnects from the PCB antenna when an external antenna is plugged in) and *not* on the PCB antenna side of C219.  I added the external antenna cable seen in the pic below.

(Last edited by RAThomas on 9 Jul 2015, 21:06)

Okay, i tried this mod but i think, it doesn't work properly.
I soldered only one external connector  (on picture below) and attached yagi antenna on it, and the signal strength wasn't better(AP 100m far from WT3020 ).
So i want to change it back (de-solder the pigtail and use the internal antenna), but i lost this little mount capacitor . So my question is, is this capacitor necessary or can i short the pads?

The purpose of those capacitors is to adjust the pcb antennas impedance to match the impedance of the transceiver (or a regular antenna). So, don't expect to reach the same signal quality that you've had before. And I don't know about the value of those parts. But I would recommend to resolder your pigtail and this time keep the unshielded part of the center wire as short as possible (1-2 mm). Look at this picture to see how manufacturers solder their pigtails: http://wiki.openwrt.org/_media/toh/tp-l … nd-v16.jpg

I am interesting to buy WT3020 but I need to mod external antenna too. It looks like there are 2 mod methods here, cut antenna trace method and desolder cap method. Which one is the best?

This product is available with an antenna for about the same price.  Also has OpenWRT Installed.
http://www.gl-inet.com/ar150/  Scroll to bottom. 
https://forum.openwrt.org/viewtopic.php?id=60123

Last update : gl-inet equivalent of this product is around 10$ more expansive that WT3020.

What about scratching of the solder mask on the groundplan on the sides of the capacitor pads.
And then mount a U.FL SMD connector.

I mean: solder the two ground taps to the, now exposed, ground planes on each side, and solder the input and output taps to the pads for the capacitor.

In my opinion that should keep the impedance matching with in reasonable levels, and possibly leave you with the ability to use the PCB antenna if you disconnect the U.FL pigtale.
(you probably need to find space for the PCB-antenna matching capacitor some place else then).

RAThomas: It seems you have some experience in this. What is your opinion on my suggested solution?