said by alan47:
does it need a coaxial cable connection to it or does it work off of the router's wireless network or does it need an ethernet cable?
None of these. A cable card plugs into a special slot in a device such as a Tivo. It is the device it plugs into that requires the coax connection.
You don't specify what kind of device you're considering, but you will need a coax drop for that device. It can be split off an existing drop, or you can have another drop run.--
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