There are a few ways to do this.
The simplest way is to use a voice command. For example, you can say "Alexa, wake me up everyday to 103.5 FM on iHeartRadio at 8 o'clock AM."
The structure of the voice command is: Alexa, wake me up [number of times (1 time, everyday, weekend)] to [radio station or song or artist] on [service: TuneIn, Amazon Music, etc.] at [exact time].
Another way is to use Routines in the Alexa app on your phone. A routine consists of a trigger condition and a consequent action.
- Open the Alexa app, tap the upper-left corner to expand the menu, and tap Routines.
- Create a new routine with "When this happens" being set as a "Schedule." The "Schedule" can be selected to be a specific time and repeat pattern.
- Then, add an action for playing a radio station of your choice (the radio station needs to be available through Alexa.). The screenshot below illustrates one possible setup.
You can edit an existing routine. In the "Edit Routine" screen, tap the three vertical dots in the upper-right corner to reveal to the options of "Play Routine" and "Delete Routine."