TV Tuner & Over The Air TV in Canada

My HP m7760n Media Center Computer has a Hauppauge 1600 TV tuner card. It indicates ATSC decoding capability. My regular LCD TV has an OVTA antenna and I receive both neighbouring US and Canadian digital broadcast channels.
EG. Buffalo NBC is 2.1 , CTV (Canadian) is 9.1 and PBS is 17.1 17.2 etc.

Why is it that my TV tuner only pulls in analogue TV channels typically some remote ones that are just fog as the others are now off the air. That makes this expensive card useless. I had no intention of buying another TV or cable for that matter.

Can anyone explain why this card does deliver what it promises? or are little men in black suits firing disrupters for all the sins I have commited!

Thanks