[Dr.Dave]

A portion of the hard drive is reserved for "on demand" programs which are transmitted in the background and stored on the hard drive for instant playback. I'm not sure how much space is reserved for this.

Here are the actual space requirements that I captured for OTA in Winnipeg using Windows Media Center. I think they are similar across the country.

   GB/hr Mbps
CTV    8 18 1080i 
CITY   8 18 1080i
Global 7 15 1080i (uses a sub-channel for Global-SD)
CBC    7 15 720P

 

[Dr.Dave]

Most newer TVs have a built-in ATSC tuner which is used to tune high-definition OTA signals. You would only need a box if you want to record or if you have a really old TV.

Here is a thread to help you get started with OTA including finding out which channels you can get at your location:

http://www.digitalhome.ca/forum/81-...*-welcome-new-members-read-these-ota-forum-instructions-before-posting-***.html