Turn down TX power on AirPort? Our floor has a blind spot so we needed to place an AirPort to cover two rooms. The AirPort in this particular room is transmitting at a higher power than needed, and its bleeding onto some areas where its unwanted. (This was found with Wifi Stumbler).

I'm running the AirPort Utility on OS X Mavericks. The room in question has an AirPort Express. I've looked in the AirPort Utility, but I don't see where I can set TX power.

How do I turn down TX power on AirPort?

Is there some sort of secret knock to use with AirPort to get into advanced settings? Or should I be using something else to configure them?
In order to set the TX Power you need an older version of the Airport utility which is available here.



Navigate to your base station > Manual Setup > AirPort > Wireless > Wireless Network Options. Once there, choose a transmit power that’s lower than 100% (you can choose between 10%, 25%, 50%, and 100%). 

Remember to Update your configuration when you’re done.