unable to connect to home wifi network

What color is the light on the bottom-right of the device?

What is your System Preferences>Network>Wi-Fi status?

Try command+space, type airport utility, return (open airport utility). Click the Internet icon, copy the message, paste. Next click the Time Capsule icon, copy the message, paste.

You can also try:

A) Hard Reset- Power up the Time Capsule for a few minutes. Hold in the reset button until you see the amber light begin to blink rapidly and keep holding for another 4-5 seconds. Release the reset button. Allow a full minute for the Time Capsule to restart to a slow, blinking amber light status. Your data AND settings will remain intact.

B) Factory Default Reset- Power off the Time Capsule for a minute or two. Hold in the reset button first, and then keep holding the reset button in while you simultaneously plug the power back in to the Time Capsule. Release the reset button when the amber light has been blinking rapidly for 4-5 seconds .Allow a full minute for the Time Capsule to restart to a slow, blinking amber light status. Your data will remain intact, your network settings will be erased.