Apple TV/FM Radio System - Manual (Page 97)

Creating and changing a password
You can create a password to limit access to the Channel
Setup dialog box and locked channels. When you set a
password, anyone choosing Channel Setup from the Setup
menu or switching to a locked channel must type the
password.
The same password applies to all locked channels.
Creating a password
Follow these steps to create a password:
1 Choose Set Channel Password from the Setup menu.
A dialog box appears.
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