How to change frequency?

How to change the frequency of my 5Ghz link. I cant find where to do that from the terminal.

Can u help me?

from http://www.mikrotik.com/testdocs/ros/2.9/interface/wireless.php :

/interface wireless set wlan1 ssid=test frequency=2442 band=2.4ghz-b/g \
   mode=ap-bridge disabled=no

thanks