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Over-the-air Digital TV Reception in Montreal
Introduction
 
Receiving over-the-air DTV channels in Montreal is challenging. (I am located in the middle of the NDG district of Montreal.) I have carried out several experiments since 2006. The most successful results are summarized in this note. I hope that you will find it useful.
 
To find an estimate of what channels you might receive, you can use use the online tool www.tvfool.com.
 
I am receiving all of the Montreal-area DTV channels, including CBFT-2 (19), CBMT-6 (21), CFTM-10 (10), CFCF-12 (12), CKMI-15 (15), CIVM-17 (26),CFJP-35 (35), CJNT-62 (49), WCAX-3 (22), WPTZ-5 (14), WVNY-22 (13), WETK-33 (32), WFFF-44 (43), and WCFE-57 (38).
 
There are two channel numbers associated with a TV station. For example, CBMT-6 calls itself Ch 6 because it was broadcasting on Ch 6 with its analog transmitter since the 1950's. In 2006, CBMT started up a second transmitter for DTV, on Ch 21. So when you get your new digital TV you have to tune it to Ch 21. It then "learns" that Ch 21 belongs to CBMT and that it actually prefers to call itself "CBMT-6." From then on, you will get CBMT (21) by pressing 6. How confusing! Usually with a new TV you simply do a "scan", which finds all of the available channels and their preferred names.
 
My Antennas
 
To get the US channels, almost any UHF antenna with 10 dBd of gain is okay. Channel Master, Winegard and others are all pretty good. I am using a UHF yagi/corner reflector (I call it a YCR for short) and a rotor. I hacksawed it off the front end of an old VHF-UHF antenna, and threw away the VHF part. (photo).
 
The most important factor by far is the antenna's location. Keep it at least 5 ft above the average rooftop height in your area. My antenna is about 5 ft above the roof and 31 ft above the ground.
 
Many people think that a high gain antenna is the best. This is not necessarily true. A low gain antenna has a broad beam, so you don't have to keep fussing with the rotor when surfing channels.
 
WVNY --A Special Case
 
ABC's WVNY is a problem. It is weak and on VHF Ch. 13. For this one channel I put a separate antenna, a Delhi 10Y-13S 10 element yagi. It is about 36 ft above the ground. I get a very solid signal, measuring 4-5 bars on a scale of 10, where 2 is enough. It's connected to the UHF antenna using a VHF/UHF coupler. That way I only need one downlead to the TV.
 
It is bad news is that Delhi antennas are no longer available. I don't have any experience with other yagis, so I don't know how well they would work. I'd be tempted to try the Winegard YA-1713. Its reported gain is 10 dBd, the same as the Delhi.
 
I once had a big log periodic (a Channel Master 3671, now scrapped) and it could not get Ch 13; I don't know why. This is very surprising, because its Ch 13 gain is about 10 dBd, same as the Delhi yagi.
 
I found that a layer of heavy wet snow or 1 cm of ice on the yagi could completely wipe out the signal. So far, this has happened twice.
 
My original intent was to receive the UHF channels plus WVNY-13. In spite of this, my setup also works perfectly fine for the VHF channels CFTM-10 and CFCF-12. Since they are strong, they come in, even though it's the wrong kind of antenna (Ch 13 yagi) that is pointed in the wrong direction (to the USA).
 
My TV and Tuners
 
I have a pre-2007 Sony 30" CRT. It doesn't have an ATSC digital tuner so I need an external one. I've had a few tuners over the years. My old Samsung SIR-T451 was not that good at dealing with weak signals and multipath. The more recent Samsung DTB-H260F was a huge improvement. Most recently I got a Channel Master 7000. It has two tuners and a digital recorder (DVR). It can record about 30 hours of HD. It is really good.
 
On Signal Strength Meters
 
"Signal strength meter" is the wrong name for that thing on your tuner. It is really measuring the signal-to-noise ratio (SNR). You need about a 20 dB SNR to get a DTV tuner to lock.
 
Since it's the SNR that counts, this explains why boosting the signal strength may not solve your reception problems. For DTV, the following factors are considererd to be "noise" and can lead to a low meter reading: (a) weak signal, (b) multipath (c) co-channel interference (d) adjacent-channel interference, (e) preamp intermodulation distortion.
 
With analog TV these problems are easy to diagnose as snow, ghosts, a venetian-blind picture, or intermod/adjacent channels. With DTV you are in the dark-- it can take a lot of experimentation to figure out which of these effects is the source of your reception problem.
 
Buying Stuff
 
You can buy antennas locally, from Montcalm Electronique in Laval, Raybel Electronique in Montreal, or Mastervox in Longueuil. These people can help you buy all the right parts.
 
If your TV is pre-2007 it might not have an ATSC tuner built in. In that case you'll have to buy an "ATSC set top box". These boxes are 100 percent legal, but are difficult to find in Canadian stores. (Consumer awareness is low, so stores won't stock the product.) Also note that the cheaper boxes only have the yellow video plug and no HD output, so you'll get to watch all the digital shows but it will be in low definition. The nicer boxes have HDMI or DVI outputs for true HD. I bought my tuners from online stores. Another option is to drive down to Burlington VT or Plattsburgh NY and get one there.
 
Summary
 
For WVNY I recommend a 10 element Ch 13 yagi --if you can find one! For everything else, a UHF antennna with 10 dBd of gain should do it. You'll probably need a rotor since the Canadian and US channels are in different directions. The antennas should be outdoors, at least 5 ft higher than the average rooftop height.
 
R. Paknys, paknys[at]ece.concordia.ca. Last update March 3, 2013.