My clock radio has HD but no AM, so it's been useful since 680 is my preferred wakeup station.

CIRV HD is already on with the main plus 3 sub channels ( all ethnic). I should also point out that HD is really the only way to get The Grand ( outside of the internet stream) in this area but the signal is only as good as an HD lock on the KX station and drop outs are common, I am in Pickering. HD is better than an internet stream quality-wise,

Last edited by Fitz (January 12, 2019 6:13 pm)

I am quite impressed with this Directed HD radio. The main problem is the sameness of most of the programing.

I have been able to tune in all kinds of American FM stations with the RBDS information on most. Have been able to pick up stations from Rochester and even Erie Penn. Was able to pick up the oldies station from Peterborough on 96.7. The classic rock and community stations from Cobourg. My FM and Bob FM.

There's two area stations with FM translators and a sperate HD broadcast. That gives one a chance to compare the analog vs digital on the same radio and try and figure out the impact of digital compression ( granted that even the analog broadcast may be playing digital files). 

Below is a two min clip of  two stations. Each station has the HD for 30 secs and the analog FM translator. The first station is playing Fludd and the second Elton John. I won't say what comes first on each track, the digi or analog. WAV file not MP3.

Also the selectivity of the radio is good to be able to pick up both translators from where I live in Pickering.

Analog VS Digital

Last edited by Fitz (January 15, 2019 9:37 am)

CHUM FM will not be running HD any time soon, from what I hear. 
The balance of stations which broadcast from the CN Tower, will need to have an upgrade to the "Master FM" antenna.  This is not a simple matter, given the fact that so many stations are multiplexed into the 40-something year old antenna.  Not only a rebuild or replacement is envisioned, but that's a very big and expensive project.   Again, to my knowledge this is not proceeding at a fast pace.  This is a $$$$$ issue, and some of the CN tower operators may not have the appetite for a big expensive upgrade (thinking of Jazz FM, which is fiscally strapped)  Besides, Rogers has their AM's on HD-2 and HD-3 from FCP.   CKFM's operation in HD, is due to the fact that Bell has utilized an existing aperture on the tower (which they own) for their HD antenna.

At First Canadian Place, it's a whole different ball game.   At FCP, most stations "own" their own antennas, and there is adequate power at the site for most broadcasters to upgrade to HD operation. So, in 2019 we will likely see HD operation by CIND and Flow 93 (or whatever it's called these days).

https://www.americanradiohistory.com/CANADA/Archive-Broadcast-Technology/1975%2012-00%20-%20BET.pdf

The issue with HD, as I understand it, and perhaps some engineers can weigh in, is that the digital (HD) subcarriers add about 10% (additional RF) to the existing envelope of RF going into the antenna.   Across the FM band, at the CN Tower, that's a significant amount of additional RF into a very old antenna.  I had been told that the Master FM antenna, was "maxed out" in terms of the amount of RF that it can handle. (not just a combiner issue).   Consider that CHFI operates at 44 KW ERP, CBL-FM 38 kw ERP  and there are several other high power (grandfathered) Class C stations.   I also understand that a typical Nautel transmitter (HD) may consume more power than an older analog transmitter.  So there may be an electrical upgrade (plus standby power generation) required for all stations to transition to HD & HVAC upgrades.  My recollection is that the master antenna at the Empire State Building which was quite old, also required a major upgrade to transition NYC stations to HD.   I also understand that with CKFM (and initially for CHUM-FM), the RF for the HD digital subcarriers, is routed into a separate antenna, so the HD component by-passes the Master FM antenna. I recall that Scott Fybush did a comprehensive article of the NYC Empire State Building master antenna system a few years back.

One might speculate that from a status quo situation, various stations that use the Master FM antenna could reduce the Analog ERP, while adding HD Digital subcarriers, but that would impact their analog coverage, which no general manager would likely choose to do.  

here is an interesting article on the Empire State Building antenna rebuild - by Fybush:
https://www.radioworld.com/news-and-business/under-a-cocoon-esb-plans-for-new-fm-era
 

Last edited by tvguy (January 15, 2019 9:56 pm)

tvguy wrote:

The issue with HD, as I understand it, and perhaps some engineers can weigh in, is that the digital (HD) subcarriers add about 10% (additional RF) to the existing envelope of RF going into the antenna.   Across the FM band, at the CN Tower, that's a significant amount of additional RF into a very old antenna.  I had been told that the Master FM antenna, was "maxed out" in terms of the amount of RF that it can handle. (not just a combiner issue).   Consider that CHFI operates at 44 KW ERP, CBL-FM 38 kw ERP  and there are several other high power (grandfathered) Class C stations.   I also understand that a typical Nautel transmitter (HD) may consume more power than an older analog transmitter.  So there may be an electrical upgrade (plus standby power generation) required for all stations to transition to HD & HVAC upgrades.  My recollection is that the master antenna at the Empire State Building which was quite old, also required a major upgrade to transition NYC stations to HD.   I also understand that with CKFM (and initially for CHUM-FM), the RF for the HD digital subcarriers, is routed into a separate antenna, so the HD component by-passes the Master FM antenna. I recall that Scott Fybush did a comprehensive article of the NYC Empire State Building master antenna system a few years back.

One might speculate that from a status quo situation, various stations that use the Master FM antenna could reduce the Analog ERP, while adding HD Digital subcarriers, but that would impact their analog coverage, which no general manager would likely choose to do.  

here is an interesting article on the Empire State Building antenna rebuild - by Fybush:
https://www.radioworld.com/news-and-business/under-a-cocoon-esb-plans-for-new-fm-era
 

Looks like the CN Tower will be stuck doing analog unless this gets one day pushed as mandatory such as it did with tv.  Then you'll see the money being spent to get this all sorted.

Wasnt it not Bell that caused a fire in the mast in 2017 due to HD?  

Tim Brown 2016 wrote:

markow202 wrote:

Looks like the CN Tower will be stuck doing analog unless this gets one day pushed as mandatory such as it did with tv.  Then you'll see the money being spent to get this all sorted.

Wasnt it not Bell that caused a fire in the mast in 2017 due to HD?  

I confess, it doesn't look promising based on tvguy's insights. Nevertheless, at some point the Master FM antenna will start to fail due to age. The fact it's had a fair degree of protection from the elements because of the radome will perhaps delay the need to replace it by several years.
?

If it hasn't failed by now, it will be fine.  Besides, I believe the transmitters more of an issue on failing last time I saw a Fybush article of 2015 all transmitters seem brand new.  

https://www.fybush.com/site-20150529/ 

There is no good reason for Bell to put HD on more than one FM in each market.

I don't see it on CKLH either as CHAM and CKOC are just syndication clearing houses.

CHRE makes sense; maybe they'll be next.

I had heard, that someone in "programming" at Bell, did not "like" the coverage of CHUM-FM in the fringe areas, when it operated with HD, hence when HD operations were restored, only CKFM operated in HD - because it is the lesser of the two stations in terms of ratings/revenues.  There was no sound basis from an engineering standpoint for coming to this conclusion.  There is some possibility that when the Master FM antenna is upgraded, which is taking a long time, due to covid and likely financial pressures on the tenants,  you will see a number of stations from CN tower upgrade.  In a matter of weeks, look for HD on CJKX 95.9 in downtown toronto.   They have been approved for HD operation for the repeater which is on First Cdn Place and the equipment may have been installed.  Right now, the downtown repeater is analog only and nulls out the HD subcarriers from Durham region on the frequency.

tvguy wrote:

In a matter of weeks, look for HD on CJKX 95.9 in downtown toronto.   They have been approved for HD operation for the repeater which is on First Cdn Place and the equipment may have been installed.  Right now, the downtown repeater is analog only and nulls out the HD subcarriers from Durham region on the frequency.

That one's interesting, as I find the analog/analog transition from the Oshawa signal to the Toronto signal imperfect, specifically once you get on the DVP. Will this help?

And again, I don't know of a single cluster in the country that has more than one of its FMs on HD, and for the most part it's not due to technical limitations. There is next to no consumer awareness of the technology, and I see no sign that it will be used as anything but a band-aid to help in-cluster AMs.
 

torontostan wrote:

How much coverage would be lost if the CN tower FMs moved to FCP and increased their power to compensate for lost height? There's also that new skyscraper at Yonge & Bloor that will actually be taller than FCP. Instead of a costly Master re-build, could we see those who want an upgrade move altogether? 

With the TV stations it always made sense to be at the southernmost possible point in Toronto, so that people pointing their antennas towards Buffalo would get Toronto stations as well. This isn't the case for FM, so I wonder if much would be lost with a move to FCP or Y&B. 

Also how much interference will occur with all these super-tall condos and office towers popping up in the last few years? The CN tower is slowly becoming a less desirable place to have an antenna. 

FCP was never as good as CN but yes that could be due to power.  I think that roof would also be super jammed if this occured.  CN is still the tallest over the entire city. but, good analogy I thought about this once.

Why is the CN Tower a less desirable place?

Last edited by markow202 (June 16, 2021 5:36 pm)

RadioAaron wrote:

tvguy wrote:

In a matter of weeks, look for HD on CJKX 95.9 in downtown toronto.   They have been approved for HD operation for the repeater which is on First Cdn Place and the equipment may have been installed.  Right now, the downtown repeater is analog only and nulls out the HD subcarriers from Durham region on the frequency.

That one's interesting, as I find the analog/analog transition from the Oshawa signal to the Toronto signal imperfect, specifically once you get on the DVP. Will this help?
 
 

There is no simple answer as to how effective an HD repeater will be.  There are a number of variables that can be tweaked to optimize the reception area. With synchronous repeaters, there is always some degree of interference between the two signals, creating a "mush zone". For analog signals, the conventional wisdom has been to "synchronize everything", that is to say the carrier frequencies are locked using GPS, and the modulation tracking within 0.1 dB.  The 19 kHz stereo pilot must also be locked. Then the audio modulation can be offset (by microseconds) so that the main and repeater signals arrive at the desired location at the same time.  The effective radiated power and antenna pattern of the repeater are two more variables.

For a given reception point, the difference in dB that must be achieved between the desired repeater signal and the undesired main signal will vary dramatically with the amount of error in the arrival time of the two signals. When the reception point is in line with both transmitters, the timing error can be reduced to zero, but as you move away from that straight line, the error will increase to the point where the interference becomes evident.  In the case of CJKX, the area west of First Canadian Place will likely have the best and most consistent signal quality.  Areas to the east will likely have drastic variations. 

There is very sophisticated software that allows playing with these variables to optimize the size and location of the interference-free reception zone for the repeater. Another factor which you can't really control is terrain obstruction.  Repeaters work best when the main signal has a lot of blockage. 

The hybrid digital signal requires a lower desired/undesired ratio between the two signals, and therefore the interference-free reception area of the repeated HD signal in theory should be significantly larger than that of the analog signal.

All this to say that the success of the CKJX-HD repeater will depend on whether they employ all of the available techniques, and purchase the additional equipment which will allow precision synchronization and adjustment of the aforementioned variables. 

Stay tuned.

 

Last edited by Skywave (June 19, 2021 5:43 pm)

Juggie1 wrote:

Biggest issue with FCP is Safety Code 6! With the current load of rf stations including tv, fm, and communications companies, the rf level is at or just below the level where power reductions would start happening. Adding stations up there would further reduce the current power levels of existing stations and may even mean that the top floors may not be useable.

Also, FCP is just under 1000 feet and the CN master fm antenna is just under 1600 feet up! That height difference means much better reach at a much lower power level and a big hydro savings! Also lower maintenance costs at CN tower as only one antenna system to maintain. FCP would have to either spend lots of money for a common antenna system or each station would have to put big filters in to prevent reradiation issues!

Very interesting! I assume no FCP broadcasters are currently inhibited by these regulations? As in, are any operating at a lower power to limit overall radiation? 

I'm shocked people are allowed to work on the upper floors full-time as it stands now.... I wouldn't be surprised if the levels of radiation result in higher cancer rates among those BMO staffers. 

I guess all I'm wondering is if it would be cheaper (and easier) to move the CN FMs to FCP (and possibly include even more FMs on an Onmi-Directional Master FM system there), rather than upgrading the almost 50 year old systems at CN in their limited space and inaccessible spire.