How long can Alexa echo dot play a radio station , in minutes or hours

The Amazon Echo Dot, or any Alexa-enabled device, can play a radio station continuously as long as it is connected to power and the internet. There isn't a specific time limit on how long it can stream a radio station, so it could play for hours or even days if left unchecked. Just keep in mind that the device may enter a low power mode if it doesn't detect any voice commands or interaction for a while, but it will resume playing if you issue another command.