iMac late 2012 wifi
I have a Late 2012 iMac that supports the N band for wifi No AC. I also have a MBA early 2015 that supports AC connections. I have my Sagemom Router / Modem that is broadcasting BOTH N @ 2.4 GHz Channel 2 and AC @ 5 GHz Channel 36. Both Bands have the same SSID but on different Channels
The iMac is connecting on the 5 GHz Channel 35 but as an N connection.
How do I force the iMac to connect to the Router / Modem on the 2.4 GHZ "N".
Any suggestions appreciated.
MacBook Air (13-inch, Early 2015), OS X Yosemite (10.10.2)