Listen to Carolina 440 System, K4JDR 441.725 MHz - Raleigh

Scanner Radio is a free app on iOS and Android that lets you listen to police, fire, EMS and other public safety radio across 7,000+ scanners around the world.

Yes. Listening to Carolina 440 System, K4JDR 441.725 MHz - Raleigh on Scanner Radio is completely free on both iOS and Android.

Sometimes scanners go down for maintenance or stay quiet during low radio activity. Scanner traffic can come in bursts, so silence often just means a quiet moment.

In Scanner Radio, you can enable push notifications that let you know when listener numbers on a feed suddenly spike, or when there is a major breaking news story.

Dispatchers use 10-codes and signals as shorthand. Scanner Radio includes a built-in 10-code reference so you can follow along. Police Scanner Codes Explained: The Complete 10-Code Guide.