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January 3, 2021 5:10 pm  #1


Cable 5 and 9 question

Can someone explain to me why, at least in analogue days, a local TV station could not be on the same broadcast and cable channel? , CBLT 5 has always been on cable channel 6 for as long as I can remember and CFTO channel 9 has always been on cable 8. From a marketing perspective it would make more sense for broadcast channel 5 to be on cable 5 and broadcast channel 9 to be on cable 9 so I assume there's a technical reason why they aren't? I don't know about today since I no longer have cable but at least in the analog era this also meant that cable 5 and 9 were basically unusable because of interference from the broadcast channels - initially I think Rogers had CBS and ABC on those channels and then duplicated them higher up (meaning you were basically out of luck if you had basic cable with no converter in the 70s and 80s - which at the time was channels 2 to 13) and later they put up teletext channels (TV listings and Broadcast News, as I recall). 

 

January 3, 2021 5:43 pm  #2


Re: Cable 5 and 9 question

The reason for the channel offset was due to many TV's in relatively close proximity to the transmitters (channel 9 at McCowan and the 401, channel 5 on Jarvis Street, and in later years the CN Tower) would pick up the signal directly.  Often the cable TV "coax" on the TV would act as an antenna.  When the off-air signal was mixed with the cable TV signal, it would render the picture unusable.  Thus the cable operators would always distribute a local broadcast signal on an adjacent channel.  In Hamilton, for example, CHCH channel 11 was on cable channel 10 (I believe).  This also posed an interesting problem for VCR's (remember those?) which usually output their signal on channel 3.  There was a switch to change the output to channel 2, for those markets where there was a local channel 3 broadcaster (such as CKVR Barrie).

 

January 3, 2021 5:53 pm  #3


Re: Cable 5 and 9 question

I remember my VCRs had a choice of either channel 3 or channel 4 as playback. I always opted for channel 3, which was the default setting. 

https://i.ibb.co/QpYPKZW/Early-VCR-Ad-TV-Guide-March-25-31-1978.jpg

 

January 3, 2021 6:12 pm  #4


Re: Cable 5 and 9 question

"Go see HIM and start watching Selectavision"  Ha!

 

January 3, 2021 6:18 pm  #5


Re: Cable 5 and 9 question

In Phase wrote:

The reason for the channel offset was due to many TV's in relatively close proximity to the transmitters (channel 9 at McCowan and the 401, channel 5 on Jarvis Street, and in later years the CN Tower) would pick up the signal directly.  Often the cable TV "coax" on the TV would act as an antenna.  When the off-air signal was mixed with the cable TV signal, it would render the picture unusable.  Thus the cable operators would always distribute a local broadcast signal on an adjacent channel.  In Hamilton, for example, CHCH channel 11 was on cable channel 10 (I believe).  This also posed an interesting problem for VCR's (remember those?) which usually output their signal on channel 3.  There was a switch to change the output to channel 2, for those markets where there was a local channel 3 broadcaster (such as CKVR Barrie).

Thanks for the explanation. Is this still an issue now that OTA has transitioned to digital?
 

     Thread Starter
 

January 3, 2021 7:39 pm  #6


Re: Cable 5 and 9 question

I think people sometimes forget just how revolutionary the VCR was. It did away once and for all with the tyranny of the TV schedules. You could watch anything you wanted any time you wanted. That was never possible before. I remember when the very first RCA Selectavision came out in 1977. I had just started to work nights at CKEY and I was missing all my favourite shows. 

When I saw the first one, money was no object. This was the most must-have machine I ever purchased. And at the time, it cost me over a thousands dollars. (It was only later that they came down in price.) 

I had been waiting my whole life for it and finally, they were available. Over the years, I must have owned about 10 of them, as the heads wore out and were replaced, putting them in various rooms of the house. I still have a DVD-VCR hybrid I'm not sure I ever used. It's nearly brand new. 

Odd that this would come up. Two days ago, I was looking down my basement for something and came upon a box I didn't recognize. Inside were five fresh never opened VHS tapes, still in the cellophane. I wonder if they're worth anything?

 

January 3, 2021 7:46 pm  #7


Re: Cable 5 and 9 question

“In the beginning”  cable TV was MATV. That is to say, it was a master antenna system. It was to bring TV signals into ones home. For instance if you lived in the GTA, you could not watch CFTO on ch. 9 and cable 9 a the same time. It would ghost. Hence “channel 9 cable 8”.

Today I am sure coax cabling standards are much tighter. Remember in many homes, internet comes through the the cable system.

Also keep in mind that CFTO is now on RF 8.

 

January 3, 2021 8:01 pm  #8


Re: Cable 5 and 9 question

RadioActive wrote:

I remember my VCRs had a choice of either channel 3 or channel 4 as playback. I always opted for channel 3, which was the default setting.

I knew someone near Calgary that used Channel 4 for their VCR. Which was strange because in the analog days that was the channel for CFCN-TV in Calgary.

May have been because they had cable and perhaps Cable 3 was used and Cable 4 was vacant. (CFCN was on Cable 5 back then, I don’t know what was on 3 or 4, just speculation)

Last edited by MJ Vancouver (January 3, 2021 8:03 pm)

 

January 3, 2021 11:48 pm  #9


Re: Cable 5 and 9 question

Hansa wrote:

In Phase wrote:

The reason for the channel offset was due to many TV's in relatively close proximity to the transmitters (channel 9 at McCowan and the 401, channel 5 on Jarvis Street, and in later years the CN Tower) would pick up the signal directly.  Often the cable TV "coax" on the TV would act as an antenna.  When the off-air signal was mixed with the cable TV signal, it would render the picture unusable.  Thus the cable operators would always distribute a local broadcast signal on an adjacent channel.  In Hamilton, for example, CHCH channel 11 was on cable channel 10 (I believe).  This also posed an interesting problem for VCR's (remember those?) which usually output their signal on channel 3.  There was a switch to change the output to channel 2, for those markets where there was a local channel 3 broadcaster (such as CKVR Barrie).

Thanks for the explanation. Is this still an issue now that OTA has transitioned to digital?
 

Short answer:  It is no longer an issue.

Somewhat longer answer:  Cable has also transitioned to digital however unlike the analog era, cable TV uses a different digital standard than broadcast OTA.  Although cable still uses "RF carriers" to transport their signals, including internet, and there remains some sharing of frequencies with OTA broadcast, set-top-boxes or cable modems will not be bothered given that the cable signal would be much stronger, and in a different format, than any broadcast OTA signal that might squeak its way in.
 

 

January 4, 2021 11:52 am  #10


Re: Cable 5 and 9 question

Believe it or not, "ingress" can still be an issue. Here in Rochester, the TV stations are all at a shared tower site, Pinnacle Hill, just southeast of downtown. Two of our stations, WHEC and WHAM-TV, operate on VHF RF channels, 10 and 9 respectively.

Spectrum Cable uses one of those same RF channels, 9, to distribute WHAM's HD signal around its system. Cable uses a different modulation scheme (QAM) for its digital signals - but there is absolutely a problem in areas around Pinnacle Hill (including here at my house) where the strong OTA signal on RF 9 gets into the cable receiver when the connections aren't tight or the drop to the house gets damaged, and the QAM digital signal can't decode.

WHAM's engineer tried hard to let Spectrum know there was going to be a problem when they repacked a year ago from RF 13 to RF 9 (which is why CFTO had to go from 9 to 8), but Spectrum didn't listen, and so they're constantly rolling trucks to try to "fix" a problem of their own making. 

(Also: "MATV" was literally a master antenna - whatever came in up at the antenna was amplified and piped down through the building's wiring into individual TVs. If CFTO was on 9, you'd tune your TV to 9 to watch it. "CATV" started out as the abbreviation for "community antenna TV," and some of those systems did remodulate signals onto new channels, especially UHF - so a CATV system in the early 1970s might get OECA on UHF 19 and remodulate it on VHF 2 or wherever. It's my understanding that at some point as early as the 70s, the CRTC imposed technical rules that required CATV/cable systems to offset local VHF channels to different channel numbers to avoid ingress, so 5 went on 6 and 9 on 8. CHCH was distant enough that it could be carried on 11 without any issues in Toronto; I assume it went on a different channel number on Hamilton systems. The FCC never had a rule like that, and probably should have. Some systems were good about it - what became the Adelphia system in Buffalo offset the VHF channels, as I recall. Others, like the one in Rochester, were very bad about it. I never had clean pictures from 8, 10 and 13 here in Rochester at any time in the analog era.) 

Last edited by fybush (January 4, 2021 11:59 am)

 

January 4, 2021 12:04 pm  #11


Re: Cable 5 and 9 question

I remember when I moved into an apartment in Mississauga near the CFRB transmitter way back in 1993.  The cable guy had to come in to set things up.  He noticed I had two VCRs (a beta and a vhs) and warned me of the signal problems I'd be having because of my location so close to the transmitter. 

He then proceeded to do me a real solid by not only re-crimping the existing cable wiring, but he even gave me several newly-crimped cables of whatever length I needed to replace my existing ones.  He wouldn't even take any money from me for the favour.  He said that, to be honest, it was to avoid a service call in the future as he has done a number of calls in houses in the area with poorly-done or decaying cables.
 

Last edited by Peter the K (January 4, 2021 12:05 pm)

 

January 4, 2021 12:14 pm  #12


Re: Cable 5 and 9 question

Yes I clearly remember channel 5 on cable always being blurry and usually carried the TV guide and channel 9 was some other weird channel before the CTS took it over.   The CBLT and CFTO channels always tried to come in on those channels (5 and 9) and actually, I remember the days when the cable tv would go out (at the centre itself) and channels 5 and 9 would be coming in as OTA over the coax.

 

 

January 4, 2021 12:15 pm  #13


Re: Cable 5 and 9 question

Also,  how come a lot of the tv channels were mostly UHF in toronto?  I mean why was CBLT and CFTO in VHF (much better signals) and the rest up in the higher UHFs?   Once you go rural, VHF was for all tv stations for the most part which im guessing can travel better. 

 

January 4, 2021 5:38 pm  #14


Re: Cable 5 and 9 question

markow202 wrote:

Also,  how come a lot of the tv channels were mostly UHF in toronto?  I mean why was CBLT and CFTO in VHF (much better signals) and the rest up in the higher UHFs?   Once you go rural, VHF was for all tv stations for the most part which im guessing can travel better. 

Canada was late to the game in an area where the airwaves were already getting crowded early on. Before CBLT hit the airwaves in 1952 (and then CHCH in 1954), the US had already licensed or allocated stations in Buffalo on 2, 4 and 7 and in Rochester on 6 (changed to 5 in '52 and then to 8 in '62) and 10. 

That left room for 3 in Barrie, either 5 or 6 in Toronto (couldn't use both since they're adjacent), either 8 or 9 in Toronto (same reason), 11 in Hamilton, 12 in Peterborough and 13 in Kitchener. 

Canada did some shuffling over the years to fit more signals in, notably the 1972 CBLT move from 6 to 5 that allowed Global to use 6 at Paris. 

If Canadian regulators hadn't been determined to fit single stations in early at smaller locations like Barrie and Peterborough, Toronto might have been able to use 3 and 13 (which might have shuffled Rochester to 12 if the 12 in Binghamton could also have moved as part of the upstate shifts of 1961-62.) Even 11 could have worked at Toronto instead of Hamilton if the Canadian regulators had wanted it that way - but the priority was to put one or two signals in a lot of places instead of five or six in one big place. 

By the time that policy started to change, the VHF channels were locked into a tight spacing net that wouldn't allow for any shifting - and so the 1970s brought 19, 25, 47 and 79 to the Toronto airwaves. 
 

 

January 5, 2021 10:15 am  #15


Re: Cable 5 and 9 question

fybush wrote:

markow202 wrote:

Also,  how come a lot of the tv channels were mostly UHF in toronto?  I mean why was CBLT and CFTO in VHF (much better signals) and the rest up in the higher UHFs?   Once you go rural, VHF was for all tv stations for the most part which im guessing can travel better. 

Canada was late to the game in an area where the airwaves were already getting crowded early on. Before CBLT hit the airwaves in 1952 (and then CHCH in 1954), the US had already licensed or allocated stations in Buffalo on 2, 4 and 7 and in Rochester on 6 (changed to 5 in '52 and then to 8 in '62) and 10. 

That left room for 3 in Barrie, either 5 or 6 in Toronto (couldn't use both since they're adjacent), either 8 or 9 in Toronto (same reason), 11 in Hamilton, 12 in Peterborough and 13 in Kitchener. 

Canada did some shuffling over the years to fit more signals in, notably the 1972 CBLT move from 6 to 5 that allowed Global to use 6 at Paris. 

If Canadian regulators hadn't been determined to fit single stations in early at smaller locations like Barrie and Peterborough, Toronto might have been able to use 3 and 13 (which might have shuffled Rochester to 12 if the 12 in Binghamton could also have moved as part of the upstate shifts of 1961-62.) Even 11 could have worked at Toronto instead of Hamilton if the Canadian regulators had wanted it that way - but the priority was to put one or two signals in a lot of places instead of five or six in one big place. 

By the time that policy started to change, the VHF channels were locked into a tight spacing net that wouldn't allow for any shifting - and so the 1970s brought 19, 25, 47 and 79 to the Toronto airwaves. 
 

Yes youre totally correct.  I totally forgot that there was already other existing VHFs nearby and this makes sense.  Actually yes when you look at it, for example CKVR Barrie started in like 1955 thats quite early vs Toronto.

 

January 12, 2021 8:15 pm  #16


Re: Cable 5 and 9 question

Similar thing to FM Cable. The over-the-air analog FM radio stations use different frequencies on Cable FM to prevent interference if they use the same frequencies as the OTA ones. I can imagine that this would of been a problem in Toronto and southern Ontario due to the crowded FM band. Now living near Kingston, I used to live in the Sudbury area and there was enough room for Cable FM signals because there were less over-the-air stations on the FM band. I dropped Cable TV/FM 20 years ago and I'm wondering if Cable FM still exists in 2021 or has it phased out due to stations streaming online?

 

January 12, 2021 10:27 pm  #17


Re: Cable 5 and 9 question

Scorpio42 wrote:

Similar thing to FM Cable. The over-the-air analog FM radio stations use different frequencies on Cable FM to prevent interference if they use the same frequencies as the OTA ones. I can imagine that this would of been a problem in Toronto and southern Ontario due to the crowded FM band. Now living near Kingston, I used to live in the Sudbury area and there was enough room for Cable FM signals because there were less over-the-air stations on the FM band. I dropped Cable TV/FM 20 years ago and I'm wondering if Cable FM still exists in 2021 or has it phased out due to stations streaming online?

Some cable companies offer them on digital cable these days. Rogers has them in the 900s. In London I recall they carried a selection of stations from London, Kitchener, and Toronto - all the Rogers-owned stations in those cities, also CBC and some other private stations, as well as the campus stations at Western and Fanshawe. They also carried at least one US station - I think WBFO, the NPR news station in Buffalo was one,.

Last edited by MJ Vancouver (January 12, 2021 10:30 pm)

 

January 13, 2021 8:40 am  #18


Re: Cable 5 and 9 question

MJ Vancouver wrote:

Scorpio42 wrote:

Similar thing to FM Cable. The over-the-air analog FM radio stations use different frequencies on Cable FM to prevent interference if they use the same frequencies as the OTA ones. I can imagine that this would of been a problem in Toronto and southern Ontario due to the crowded FM band. Now living near Kingston, I used to live in the Sudbury area and there was enough room for Cable FM signals because there were less over-the-air stations on the FM band. I dropped Cable TV/FM 20 years ago and I'm wondering if Cable FM still exists in 2021 or has it phased out due to stations streaming online?

Some cable companies offer them on digital cable these days. Rogers has them in the 900s. In London I recall they carried a selection of stations from London, Kitchener, and Toronto - all the Rogers-owned stations in those cities, also CBC and some other private stations, as well as the campus stations at Western and Fanshawe. They also carried at least one US station - I think WBFO, the NPR news station in Buffalo was one,.

Yes, In Toronto Rogers carries pretty much all the Toronto AM/FM stations, CICX Orillia, CJAX Vancouver, WNED and WBFO.in the 900 series of digital channels. This feature is not available on Ignite.