Uh-oh, on reading that application Global is saying that since the originally planned CBC tower location cannot accommodate another antenna they'll have to put CKND's new one up on the Canwest tower, which will necessitate a drop in ERP and thus curtail the coverage area:This change will result in a contour shift even though the proposed CKND-DT would transmit at its maximum allowable power. Accordingly, this change will result in a population decrease when compared to that of CKND’s current analog B contour.That goes against CRTC policy, so it will be interesting to see if it is okayed or sent back to the drawing board.

Something is not right with this application.
Canwest's supplemental brief claims CKND-PT will be operating at its maximum allowable parameters, using about 25 kW (maximum) at a HAAT of about 131 metres.
Yet the post-transition allotment for Channel 40 in Winnipeg allows for 210 kW at a HAAT of almost 250 metres.
If I was to hazard a guess, Canwest's proposed operating parameters appear to match the transitional allotment for Channel 40, which is 15 kW @ 300 metres.
It's starting to look as if someone at Canwest misread the Industry Canada allocation database!

Good catch. The application documents they plan to be on the air this fall with their post-transitional parameters:
Canwest is requesting approval for a technical amendment to the CKND-TV broadcast
licence to add a post-transitional (final) digital transmitter in Winnipeg. The digital
channel will be 40 with a maximum ERP of 25,100 Watts and will launch in the
fall/winter of 2010.
Canwest is applying for this amendment under the Commission’s new licensing
framework for over-the-air digital television services as outlined in BRP CRTC 2010-69.
CKND-TV is currently transmitting from a leased tower site which is operated by the
CBC. The CBC tower is mechanically loaded to capacity, prohibiting the addition of
another antenna. Canwest’s proposal to transmit from its own tower, located at Canwest
Place will effect a contour shift and, despite the proposed CKND-PT transmitting at its
maximum allowable power, will result in a NLB contour-covered population decrease
when compared to that of CKND’s current analog B contour.

So unless they meant that 25kW is the maximum permissible power before August 31 2011, I agree they made a mistake.
Why not apply for 25kW transitional and 200kW post-tranitional?

Is it possible that 200kW is too much for an antenna only 7.6m above the rooftop?

(And my copy of the database has 15kW as the maximum for channel 40 during transition, 210kW post transition.)

Before I jump to any more conclusions …
Is it possible CKND would have to apply separately for a power increase after Aug. 31, 2011? As I recall, CKND and other stations owned by Canwest will see their licences expire on Aug. 30, 2010 — about two months from now — as part of the CRTC's decision to do more group-based TV licences.

Before I jump to any more conclusions …
Is it possible CKND would have to apply separately for a power increase after Aug. 31, 2011? As I recall, CKND and other stations owned by Canwest will see their licences expire on Aug. 30, 2010 — about two months from now — as part of the CRTC's decision to do more group-based TV licences.
The application is ambiguous, since it talks about a post-tranitional transmitter that is launching in 2010. It doesn't hurt to make an intervention asking for a clarification -- Global will be expected to respond to the query.

I'm trying the informal route first.
Just sent a friendly e-mail to CKND requesting info. If I don't hear back, I will consider making a comment in the regulatory process.

Someone in charge of taking care of Canwest's DTV transition wrote back this morning to answer our question about CKND's application.

You are correct in stating that the maximum post-transitional technical parameters assigned by Industry Canada would in and of themselves allow for greater transmitter power and antenna height.
However, as at all sites, Safety Code 6 regulations limit the level of radiated power that can be emitted by an antenna at any given location. Our application for the CKND DTV licence is based on the "maximum allowable parameters" within the context and limits of the Safety Code 6 regulations.

So there you have it. Safety Code 6 explains it all.

Someone in charge of taking care of Canwest's DTV transition wrote back this morning to answer our question about CKND's application.

So there you have it. Safety Code 6 explains it all.
http://content.internetvideoarchive.com/content/photos/094/000395_43.jpg

We meet again, Safety Code 6 (http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/radio_guide-lignes_direct-eng.php), old friend. Damn you! I spit my last breath at thee.

I figured it was a code 6 issue -- but now the question is, is the most economical site the best site, given that the resulting contour is much smaller?

That's a good question vis-a-vis ad revenue too as their area will be so much smaller.

I think the impact on ad revenue will be insignificant. If the population of the local service area decreases by 5% and only 10% of that 5% relies on OTA, we're talking about 1/2 of 1% of viewers. Some of those viewers will likely switch to cable, sat and possibly freesat, so the net result would be negligible.

That goes against CRTC policy, so it will be interesting to see if it is okayed or sent back to the drawing board.

It also goes against IC's policy of encouraging tower sharing. Couldn't they share an antenna with CIIT? Also, the problem with the CBC tower should be temporary since CBWFT is scheduled to move to channel 51. Even if they couldn't share that antenna (I don't see why not though), once that huge channel 3 antenna is gone, they could probably put up several UHF antennas.

Although fine as a temporary measure, I have problems with the long term use of studio roof antennas.

I remember reading that global winnipeg's pretransition channel was 28,that post transition they would go back to using channel 9. I also heard that they were perhaps going to flashcut to 9.1 and simply stay on channel 9 once they went digital, thus eliminating the need for a new antenna. Any ideas as to why they would not opt to use channel 9? The higher vhf channels are suitable for digital transmission.

I was wondering how good the Satmaximum SM 1080A High gain antenna might be for OTA reception in Winnipeg. I can pick 1 up for a very reasonable price, but don't want to waste my money if it's no good. Does anyone have any feedback on this unit?
mr.silverado

You'll find that type of antenna discussed in this thread: Wacky, Tacky OTA Gear (What NOT To Buy!) (http://www.digitalhome.ca/forum/showthread.php?t=35083)

If an antenna is not on the Antenna Chart I would not buy it. ;) Please be sure to read through the MB/SK - Winnipeg, Brandon, Regina, Saskatoon, Prairies - OTA (http://www.digitalhome.ca/forum/showthread.php?t=33078) thread to understand the OTA situation where you live.

cheers

Thanks for your help. I thought the price was too good to be a unit of good quality.

Which part of Winnipeg are you in (neighbourhood or nearest major intersection)?

This has me thinking, if Global isn't going to stick with channel 9 (and why would they when they clearly only truly want to just barely cover Winnipeg OTA anyways, being owned by Shaw Cable after all), whats going to happen to the antenna and equipment for channel 9 if Global has no plans to remain there? If Channel 9 is free could the equipment be purchased at discount by CBC perhaps? If I understood correctly, the land the antenna is currently on is rented out by the CBC currently to Global. would save a lot of moving and perhaps provide a slightly more cost effective digital conversion solution and greater coverage for the CBC via VHF.

The number of elements generally determines the gain and front to back ratio of the antenna. There are a lot of good Amature Radio publications out there regarding antenna design.

But of course you'd go to our very own Antenna Research & Development forum (http://www.digitalhome.ca/forum/forumdisplay.php?f=186) first, right? :D It is packed with such information, including what you've mentioned.