James Dobosiewicz asks:
Is there a way to use AirPort Time Capsule for wireless backup only—that is, without using it as a wireless router too? I already have a non-Apple Wi-Fi router in use, and do not want to replace it quite yet.
Yes, absolutely. You can connect the Time Capsule via ethernet to the rest of the network via its WAN port, and it will be available to any computer that connects to the network, whether that Mac is using Wi-Fi or not.
In AirPort Utility, you can disable a base station offering Wi-Fi service.
Launch Applications > Utilities > AirPort Utility.
Select your base station and click the Edit button.
Read more here:: How to disable Wi-Fi base station features on a Time Capsule