How to change network address ?

[Bob Goodwin]

        I need to change the address of this computer temporarily to a
        192.168.2.? instead of 192.168.1.9 to connect to a device that I
        reset.

        There used to be a menu that I used for this but with F16/XFCE I
        am lost.

        Would someone be kind enough to tell me how to do this?

        Bob