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Router antenna hack (two to one)? Answered

I'm in the process of buying a router to add custom firmware such as ddwrt or tomato. Some of the routers have two antennas but I'd like to use just one in order to use it with a high gain antenna. I understand that some routers have a way to disable one antenna in their firmware but I will be using custom firmware. I also understand if one antenna is not disabled in software both antennas needs matching antennas so impedance matches. If impedance insn't matched antenna would not work for long. 

My question is could I not just bridge one of the antennas on the pcb to the other in order to have matching impedance? 



7 years ago

I don't know for sure about tomato but DD-WRT has web based control of which antenna is to be used for receive /transmit or both at( http://router IP address/Wireless_Advanced-wl0.asp )(on mine) Beware and test because some router/firmware versions are confused about their right and left.
The two antenna on a-b-g type routers (not always N) are diversity antennas not ganged or stacked so only one is being used at any given time.
The impedance is 50 ohms .
Even if you just pull off one antenna (without disabling one in the firmware)
the hardware would pick the usable antenna where it sees a signal to send signal to and get signal from effectively ignoring the missing antenna.
But I usually leave the extra one on just so It doesn't get lost.
Impedance still and always 50 ohms,

PS My primestar-biquad combo has yet to damage any radio connected to it in 10 years (last two years with a wrt54g running DD-WRT )


7 years ago

Its too dependent on the circuit of the actual router to give advice. What you propose won't match the impedance of the antenna.



Answer 7 years ago

I don't understand. I would think desoldering the wire from one antenna and then soldering to the board of the other connection would have almost similar impedance. Would not the only difference in impedance if any be from the wire used to bridge the connection?