Q: macbook pro wifi issues

since my upgrade to Yosemite i am continually having problems with my WiFi not connecting or dropping out. This was not a problem prior to the upgrade!!!!

When i turn off the 5ghz on the WiFi the Macbook pro late 2011 instantly connects to the 2.4 GHz without any problems.

Is there anyway i can change the settings on the laptop that it connects only to 2.4ghz until Apple sort this problem out