Press and hold the Alarm Set button while simultaneously pressing the Hour and Min buttons to select your wake-up time.
: Press and hold the TIME SET or MEM button until the digits on the display begin to flash.
This is the feature most people overlook until it's too late. While the clock runs on wall power, you must install a backup battery (usually a 9V or specific button cell, depending on the revision of your unit). Check the battery compartment on the bottom or back.
If the display becomes unresponsive, unplug the radio, remove the backup battery for 30 seconds, and then plug it back in.