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CHCH: another transmitter?

They are proposing to take over the Channel 15 allotment vacated by Sun TV for CHCH-DT. They are finding Channel 11 in DTV is not covering the same amount of area as Channel 11 analog did, or the former Channel 18 digital.
 
You might try it now - I was able to download the zip file.

Here are the proposed specs: Ch 15; TL 42-12-27 N, 79-46-27 W ; Max ERP 132 kW, Avg ERP 59 kW; HAAT 335 m

They are simply proposing to replace the current ch 11 antenna with a ch 15 antenna on the existing CHCH Stoney Creek tower, but at 26 m lower. Ch 11 operates at 6 kW max ERP and 4.5 kW avg.

The digital urban contour reaches the Niagara River at Niagara-on-the-Lake, but stops just short of Niagara Falls. However, the noise limited bounding contour covers most of western Niagara County NY, including all of Grand Island, so I don't know if this will pass muster with the FCC, as co-channel Class A station WBNF has a construction permit to flash cut to digital, broadcasting from Grand Island. If I were TCT, I would certainly oppose CHCH. CHCH claims that the proposal is within the pre-transition allotment contours of CKXT.
 
dhett said:
They are simply proposing to replace the current ch 11 antenna with a ch 15 antenna on the existing CHCH Stoney Creek tower, but at 26 m lower. Ch 11 operates at 6 kW max ERP and 4.5 kW avg.

Actually, they're proposing to use the existing CITS antenna, which is the same antenna they used for channel 18 before the transition.

The digital urban contour reaches the Niagara River at Niagara-on-the-Lake, but stops just short of Niagara Falls. However, the noise limited bounding contour covers most of western Niagara County NY, including all of Grand Island, so I don't know if this will pass muster with the FCC, as co-channel Class A station WBNF has a construction permit to flash cut to digital, broadcasting from Grand Island. If I were TCT, I would certainly oppose CHCH. CHCH claims that the proposal is within the pre-transition allotment contours of CKXT.

I recall reading that, for the purposes of international coordination, Class A stations are treated like LPs. If that's the case, WBNF-CD may not have any protection in this case.

- Trip
 
Mike Bugaj was able to download the file & sent me the application page. It of course shows exactly what Dave posted.

WBNF is indeed notified as a LP station. The now-defunct SunTV relayer is in the I-C database as Class C -- I'm not 100% certain what the international implications are of this class, but I'm almost certain it's a protected facility. So, Canadian use of channel 15 at Hamilton would have priority over WBNF.

FWIW Mike had some trouble with their server as well. I was thinking it was just due to my VERY slow connection -- this was, after all, a 14MB file -- but I downloaded a 51MB operating system update Friday night & it went fine. (albeit slowly)
 
Why don't they just do what some US DTV stations on VHF have already done, and more are in the process of doing--asking for more ERP on their current channel rather than building a new rig?

We're learning that digital TV stations need a lot more effective radiated power than we thought in order to provide adequate coverage--probably something close to their old analog visual power--and in the US the FCC is coming around, although so far on a case-by-case basis. However, as the FCC prepares to re-allocate and market upper UHF spectrum, which will force stations which were once VHF to gradually migrate back to their heritage channels and other stations to crowd into the current Channel 2 to Channel 40 range, each station will likely be given higher ERP authorization in order to overcome VHF-band noise and restore saturation coverage to its prime market areas. Sooner or later the CRTC will do likewise.
 
Bob1370 said:
Why don't they just do what some US DTV stations on VHF have already done, and more are in the process of doing--asking for more ERP on their current channel rather than building a new rig?

I'm thinking they aren't building a new rig, and channel 15 is clearly available.

As Trip says, they're using an existing antenna. I'm betting they're using either the old CKXT transmitter, or their own old ch. 18 transmitter. I don't have my copy of the Canadian DB handy but I do think this is more powerful than either of those rigs -- but at that power level, they may well be solid-state in which case retrofitting an existing transmitter for more power is often practical.

However, as the FCC prepares to re-allocate and market upper UHF spectrum, which will force stations which were once VHF to gradually migrate back to their heritage channels and other stations to crowd into the current Channel 2 to Channel 40 range, each station will likely be given higher ERP authorization in order to overcome VHF-band noise and restore saturation coverage to its prime market areas. Sooner or later the CRTC will do likewise.

From what I've read, the "incentive auction" legislation includes provisions that prohibit the FCC from requiring anyone to move from UHF to VHF. (nor from VHF-high to VHF-low) These days I won't promise that's permanent, but for the time being I don't see any significant number of full-power UHFs moving to VHF.

(I *do* see LPTVs being forced to make the move. Note that the FCC *has* been trying to clear Class A stations off their books.. Class A's can't be forced off their channels, LPTVs can..)


In Canada, there are plenty of available UHF channels, even below 40. Maybe, possibly, they *might* run out of UHF channels in the Greater Toronto Area. I don't see any shortage of UHF spectrum anywhere else in the country.
 
"the "incentive auction" legislation includes provisions that prohibit the FCC from requiring anyone to move from UHF to VHF. (nor from VHF-high to VHF-low) These days I won't promise that's permanent, but for the time being I don't see any significant number of full-power UHFs moving to VHF."

There's a strong economic incentive to move down--a truly full power, full coverage VHF needs 1/3 to 1/10 as much ERP as a U to get the same coverage. A channel 2 digital signal with 100 kW ERP will prove just as good as a channel 20 signal with 1000 kW ERP and will soak up a lot less power. The trick is getting over the noise threshold--the initial VHF authorizations called for digital stations on VHF to use maybe 5% of their old analog authorization, and that just isn't enough.
Same mistake they made in 1946-48 when they limited all stations on channels 2-13 to 5 kW TPO and no more than 50 KW ERP at 500 feet above average terrain--it just wasn't enough to cover expanding metro areas, so in 1952 they bumped it up big time, to 100 kW at 1000 to 2000 feet AAT (depending on zone) on the low Vs and 316 kW at 1000 to 2000 feet AAT (again depending on geographic zone) on the high Vs. They need to do something similar now.
 
Bob1370 said:
There's a strong economic incentive to move down--a truly full power, full coverage VHF needs 1/3 to 1/10 as much ERP as a U to get the same coverage. A channel 2 digital signal with 100 kW ERP will prove just as good as a channel 20 signal with 1000 kW ERP and will soak up a lot less power. The trick is getting over the noise threshold--the initial VHF authorizations called for digital stations on VHF to use maybe 5% of their old analog authorization, and that just isn't enough.
Same mistake they made in 1946-48 when they limited all stations on channels 2-13 to 5 kW TPO and no more than 50 KW ERP at 500 feet above average terrain--it just wasn't enough to cover expanding metro areas, so in 1952 they bumped it up big time, to 100 kW at 1000 to 2000 feet AAT (depending on zone) on the low Vs and 316 kW at 1000 to 2000 feet AAT (again depending on geographic zone) on the high Vs. They need to do something similar now.

The FCC ran a proceeding on this last fall. They asked for comments, as to whether power increases would make VHF more attractive to stations & reduce the number of high-VHF stations requesting to move to UHF.

The answers they got from engineers was that with the receiving antennas in use by many viewers, the necessary power increase would be economically impractical. Going back to authorizing 100kw low-V and 316kW high-V wouldn't be enough. Many indoor antennas were more than 10dB poorer on high-V than they were on UHF. (The Commission didn't even bother to test them on low-V: many didn't even claim to work down there) Besides, remember that comparing analog and digital powers is comparing apples to oranges. The 45kW power limit for low-V is essentially the same as 90kW analog -- the difference between 90 and 100kW is of course negligible.

To make up for the poor antennas, and the noise levels, it would probably be necessary to run powers on the order of 1000kW. (both high and low. Field strength per kW ERP is lower on high-V, but so is the noise level.) Thing is, doing that would raise the interference level in the fringe areas -- where viewers have adequate antennas. (but would need to replace them with something more directional in order to avoid co-channel interference problems...)
 
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