Details of what to expect in West Island (OTA HD)
I live in the West Island, 2km West of St-Charles boulevard, almost 1 km North of the 40, in Pierrefonds, and like most of you in this area I currently don't receive OTA HD CBC/SRC/TVA/etc. transmitted from downtown Montreal due to shadowing from Mt. Royal.
Here's what to expect for those of you living in the same area for OTA HD, following some research I did as to why to my surprise I receive CIVM-HD (17.1, Tele-Quebec) which started transmitting 2 days ago.
It's VERY promising for the future !
I have a CM4228 atop a 10 foot pole on my rooftop, pointed toward Mt. Mansfield, from which I easily get OTA HD from PBS, ABC, CBS, NBC & FOX. I also have the recommended CM preamp for that antenna in the attic (don't recall p/n). Antenna bearing is 156 degrees magnetic. According to TVFool.com range to Mt. Manfield is 82.6 miles from my home.
Since I was told 17.1 transmits from atop the Olympic Stadium, and I receive it 81%, I was surprised because I suspected Mt-Royal would shadow it. By the way apparently the transmitting power of 17.1 is slightly more than 9kW.
So I went on Google Earth and discovered why: from my location, the Olympic Stadium is actually LOS (line-of-sight). Range is 18 miles. I then checked by how much the bearing would change if/when 17.1 transmission is relocated to Mt. Royal (like many other channels are expected to be; by the way range to Mt. Royal for me is a lower 15 miles). It turns out that it would stear by 10 degrees, toward the South, i.e. the angle between Mt. Mansfield & Mt. Royal is 66 degrees, compared to the angle between the Olympic Stadium and Mt. Mansfield which is 76 degrees.
This means that most likely, when transmissions of the various channels are relocated to Mt. Royal, I should be able to receive them with no problem or needed modification to my setup, because (1) range (from 18 to 15 miles) and deviation from Mt. Mansfield (from 76 to 66 degrees) are both reduced/improved for Mt. Royal compared to the Olympic Stadium. The radiation pattern for the CM4228 is such that I will have a higher gain for transmissions from Mt. Royal compared to the Olympic Stadium at that lowered angle (I was afraid I might sit in a node with very low gain, it won't be the case). And I will surely be LOS, antenna base height at the Stadium is approx. 200m (from sea level), versus Mt. Royal which is approx 223m (mountain top) + 112m (tower) = 335m.