how do i switch radio channles?

[R E D bandit]

ok i start out in the orange channle but i want to know how to get to the green chanle how i do it?

[Auger]

The radio is pretty easy to use, but there are a lot of options.  There are 5 radio channels, and all of them can be tuned to different "frequencies".  The easiest way to tune the radio is press '/', then use the mouse to tune the frequency you want from the pull down menu next to each channel.

Detailed help is available here.