Hi,
My location is Pickering, Ontario (near the boarder of Scarborough). The house that I bought has already an antenna on top of it's roof on a long pole. I am 96% sure that this antenna is from Look Communications company that was offereing digital TV service couple of years ago. Here is a link to the picture of the antenna simillar to what I have.

http://www.look.ca/en/tv/tv_installation.html

My question is this: Can I use that antenna for receiving free HDTV on the air if I buy a HD tuner? I already have an HD projector in my basement, but it needs HD tunner. Please let me know. Thank you.

No Look-tv is in a much higher frequency.

Thank you for your response.

Hi,
The house that I bought has already an antenna on top of it's roof on a long pole.

That's the way LOOK had to install them to get line of sight. They won't come back for the antenna, so toss it but keep the cable and pole, its reusable:D

This is a California Amplifier active antenna for the frequencies between 2.3 and 3 Gigaherz.

You cannot use a Look antenna because they operate on different frequencies. But all is not lost, you can use the mast for attaching a recommended outdoor antenna and your existing cabling, but you can't use the Look antenna for OTA reception.

short answer is NO, but the forum won't let me reply with only 2 characters.
:)

At what frequency range does Look transmit?
We currently transmit at 2596-2686MHz.

You said 'we'? but your sig says bev?
Does look do any HD?

Could an OTA antenna such as the CM4221(8) be used on the same mast(assuming Look service is also maintained) without interference between signals?

The different frequency ranges should ensure no cross-interference, but I would make sure that the 2 antennas are at least 30cm apart on the mast so that the reflectors of each don't cause multipath interference with the other.

If possible the OTA antenna should be on top. If you have to move the Look antenna to do that, make sure to scribe or mark the aiming direction on its brackets and on the pole so that you can remount it elsewhere on the pole again with no fuss.

I don't know your location so I'm adding that its also possible to put a rotor up top and mount the OTA antenna on it, above the Look antenna.

Thanks very much.

I've been sniffing around for a while now, and plan on taking the HD OTA plunge shortly. I'm in Ajax ON about 1km from the lake and will likely go 4228 aimed at Buffalo with a professional install, but thought I'd inquire about the existing antenna/mast as it is at the highest point on my house.

I think you'll do just fine with OTA from where you are, peanuts, and here's the thread for your area to compare with others' results:

http://www.digitalhome.ca/forum/showthread.php?t=36538

Looking forward to seeing your results there too! :)

Would this antannae work to recieve HDTV signals? I did some research and found a link to it's specifications:
http://www.vytek.com/pro_mmds_2010-130.html

http://i70.photobucket.com/albums/i98/Scorponox/Insp5010.jpg

http://i70.photobucket.com/albums/i98/Scorponox/Insp5009.jpg

NO:
http://www.digitalhome.ca/forum/showthread.php?t=30551&highlight=looktv

The frequencies are wrong for OTA.

Now,... if your the tinkering type and you if you're in a location to mount outdoors, and signals are available to your house.....
You could remove the Look dipole and build yourself a nice custom, homemade 2 or 4 -bay antenna, depending on the size of your reflector.. Enviro-friendly, re-usable parts include the mounting system, the mesh (oven-rack) reflector, and your cabling. You might have to add some more "strands" to your reflector to get the spacings down to the required size. Of course this is assuming the the curvature on the reflector is minimal. All you need is a Balun matching transformer (Matches 300-ohm antenna to 75-ohm coax cable) & antenna wire (all for less than $15 I bet), and something to isolate the antenna wire from the reflector/mast (wooden spool perhaps).
see the OTA Build-It-Yourself Antennas & Gear (http://www.digitalhome.ca/forum/showthread.php?t=25677) thread.