Every Time Capsule includes an internal AirPort disk whose contents you can archive using AirPort Utility.
Before you can archive the contents of the Time Capsule, you need to connect an external disk to the USB port on your Time Capsule.
Open AirPort Utility, located in the Utilities folder in the Applications folder on a Mac, and in Start > All Programs > AirPort on a Windows computer.
Select the Time Capsule that contains the internal AirPort disk you want to archive, and then click Manual Setup.
Click Disks in the toolbar, select the internal AirPort disk, and then choose Archive Disk from the pop-up menu.
Choose the destination disk from the Destination pop-up menu, and then click Archive.
The Time Capsule status light blinks amber while the disk is being archived. You will not be able to change settings, update the firmware, or restart the Time Capsule until the content of the disk is archived and the Time Capsule becomes available again.