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Why Do Cable-Ready TVs Go Up To Channel 125?
- Thread starter Joey1986
- Start date
K
kenglish
Guest
That's just the way the manufacturers do it.....probably a hold-over from the days when "our new model gets more channels than their model".
Cable channels, BTW, are all across the spectrum...they go 2-6, then 95-99 (overlapping the FM OTA frequencies), then 14-22 (between the OTA TV bands), then 7-13 (same frequencies as OTA TV), then 23-94, then 100 and up.
As Cable converts to all-digital, you won't need most of the channels at all.....only the primary program streams of your locals will be analog, and eventually ALL analog will go away on Cable.
Cable channels, BTW, are all across the spectrum...they go 2-6, then 95-99 (overlapping the FM OTA frequencies), then 14-22 (between the OTA TV bands), then 7-13 (same frequencies as OTA TV), then 23-94, then 100 and up.
As Cable converts to all-digital, you won't need most of the channels at all.....only the primary program streams of your locals will be analog, and eventually ALL analog will go away on Cable.
kenglish said:
The actual analog cable channel frequencies are:
0-1: 38-50 MHz (IIRC, some systems actually use these. Note that Channel 1 is the same as the late '40s version)
2-4: 54-72 MHz (same as OTA)
5-6: 76-88 MHz (same as OTA)
7-13: 174-216 MHz (same as OTA)
14-22: 120-174 MHz
23-64: 216-468 MHz
65-94: 468-648 MHz (2 MHz below OTA Chs. 14-43)
95-99: 90-120 MHz (A visual carrier shift is sometimes necessary on 98 & 99 to avoid interference to aircraft channels)
100-125: 648-804 MHz (2 MHz below OTA Chs. 44-69)
126-158: 804-1002 MHz (Noted in some texts, but I've never seen a TV that tunes this high)
Cable channels 57-61 (420-450) can be used to receive ham TV by connecting a UHF antenna while having the TV set to "cable." Theoretically, so could Channels 143-145 (906-924 MHz) if you have a set that works on those frequencies (again, I've never heard of one but I have seen those channels specified)
Most TVs can still pick up OTA stations in the "cable" position even though the broadcast frequencies are 2 MHz above the cable channel. For example, Channel 15 can be received on a TV set to "cable" on Channel 66. This, of course, becomes irrelevant on June 12.
I'll definitely like it when WJKT Fox 16 in Jackson, TN shuts down their analog transmitter. I live about 2 miles away from their tower and it causes interference on some TVs on cable channel 67, which is Nick and my daughter watches it at times. Once the analog signal is off that will go away.
On the new LCD tvs are they going up to 125 channels also? I would say more as if you have a cable card for your tv it needs to go past 125 for digital cable.
Also has anyone ever had cable hooked to their tv but the tv was set to antenna mode channels 2 - 69. You will notice that cable channels in the high 60s and up will show on 14 and into the 20s.
Also has anyone ever had cable hooked to their tv but the tv was set to antenna mode channels 2 - 69. You will notice that cable channels in the high 60s and up will show on 14 and into the 20s.
Our local cable system used to have all the analog channels from 2 to 74. A couple years ago the channels 70-74 were shifted up to 100-105, and digital channels were added in the 70s. I believe Rogers said the reason was that they could get better reception on the frequencies for channels 100-105.
I do remember the older CATV ready sets very well. Still have some of them and boy do they have issues. Between channels 95-99, on some of them, they tend to pick up some interference from the local FM stations. When I would pass by those channels, that would scare me because I didn't understand why this was happening. Now that I'm older and more educated, I learned
why that issue occured. Since I live near a radio station tower, (WDXX Dixie !00) the signal will actually bleed into the TV. (Their tall tower, is less than a mile from my house and is located behind Wal-Mart) You could hear the music and programming but couldn't see no one. Little lines would appear all over the screen. Thanks to Leo Leport from the old Calling for Help Computer TV Program for educating me on that one.
Even the older Decoder CATV Boxes would have that issue too. Remember one we used to have from the old TeleCable company. This one would actually pick up three different radio stations, on channels 71-73 and little lines would appear on each channel. This box was made by Zenith and had a nice brown look to it. It was the model that came out during the 80s. This was the one that had a big silver remote control to it.
R.D.P. <><
why that issue occured. Since I live near a radio station tower, (WDXX Dixie !00) the signal will actually bleed into the TV. (Their tall tower, is less than a mile from my house and is located behind Wal-Mart) You could hear the music and programming but couldn't see no one. Little lines would appear all over the screen. Thanks to Leo Leport from the old Calling for Help Computer TV Program for educating me on that one.
Even the older Decoder CATV Boxes would have that issue too. Remember one we used to have from the old TeleCable company. This one would actually pick up three different radio stations, on channels 71-73 and little lines would appear on each channel. This box was made by Zenith and had a nice brown look to it. It was the model that came out during the 80s. This was the one that had a big silver remote control to it.
R.D.P. <><
I remember my first "cable-ready" TV in the late 80s/early 90s (Montgomery Ward Model made by Sharp) would only go up to channel 36 when you switch from ANT to cable. It didn't bother me until later when my cable company added more channels past 36 and started putting the good channels on higher numbers and the crap channels on lower numbers. I never understood the 36 channel limit on those early cable ready TVs
Mastaclocksetta said:
Cable Channel 125 = OTA Channel 69. Since OTA (pre-digital) doesn't go above that, and cable headend bandwidth max's out at about 850 MHz, there was no need for more channels.
I had a TV once that had cable channels 126-139, which corresponded to OTA channels 70-83 (which was done away with in the 60's, but some TV's, notabily Zenith TV's, still had the capability to tune these channels through in models made through the late 90's).
Why Channels 95-99 were assigned to the frequency range around the FM band is beyond me (this was when most cable systems stopped at channel 36 in the 80's). Many cable companies never bothered to use these channels at all, and maxed out at the highest number in the sequence.
Now...everything (OTA and cable) is going to digital, this becomes irrelevant. OTA channel 10-1 can be located at physical OTA channel 25-3 and cable channel 549 can be located at physical cable channel 105-610. As long as it is simple for the consumer, it will be fine.
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kenrayc
Guest
When I bypass the digital cable box and connect my cable directly to the cable input of my LCD TV(my TV has separate input for OTA and cable) I recieve all my locals and sub channel on the same mapped channel as my local OTA .NBC 24 is on 24-1,24-2 is weather plus and so forth.They put ION on74-4,WGN on 74-5,and The weather Channel on74-6. weather scan on 104-20 and several shopping and informecial channels in between.
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kenglish
Guest
The thing I hate, though....
Many manufacturers design their sets to automatically assume you have Cable TV, and scan that channel plan first. If they see ANY signals in the mid-band spectrum, they finish a Cable scan, and never even look for OTA channels.
So, when someone tells me they "get KJZZ-14 on channel 65", I know their set is one of those "pigs". I also know they don't get some of the higher-numbered UHF stations.
And, if it's a Digital TV, it won't find ANY digital channels at all, since it assumed the set to be on Cable, and only searched for QAM, not ATSC/8VSB. For the "fix", you have to go much deeper in to the setup menu, skipping the "E-Z Set-up" stuff.
Why can't "Easy", be really "Easy"? Like, in "Reliable"? ???
Many manufacturers design their sets to automatically assume you have Cable TV, and scan that channel plan first. If they see ANY signals in the mid-band spectrum, they finish a Cable scan, and never even look for OTA channels.
So, when someone tells me they "get KJZZ-14 on channel 65", I know their set is one of those "pigs". I also know they don't get some of the higher-numbered UHF stations.
And, if it's a Digital TV, it won't find ANY digital channels at all, since it assumed the set to be on Cable, and only searched for QAM, not ATSC/8VSB. For the "fix", you have to go much deeper in to the setup menu, skipping the "E-Z Set-up" stuff.
Why can't "Easy", be really "Easy"? Like, in "Reliable"? ???
I have seen people who think they can only pick up 2 channels because their tv is stuck on cable and will only pick up VHF. I wish they had designed TV to stay on "antenna". My new HDTV resets to "cable" if you hit the reset button in the setup menu. Very annoying. My VCR used to automatically switch to cable whenever the lights blinked. Making my VCR useless unless I had the original remote, which eventually broke btw. and i couldn't find a universal remote that would let me get into the the menu screen
K
kenrayc
Guest
flytrap said:
I have the same problem with one of my analog TVs ,but reverse mine is stuck on Antenna and the original remote broke long ago,It's a sharp and I tried every possible universal remote ,can't get into the menu I only have one HD/DVR cable box and the other outlets are direct with in this case I only get 2-13. my analog cable stops at channel 69 so no cable station on UHF.
Interesting......
10 years ago or so a friend of mine said he had a 1000 channel SONY CABLE READY TV and he scanned above 100 all the way and he found some interesting things!
140 - Test pattern
And when he hit the 800s he heard music on about 30 or so of them.......
Has anyone else ever explored the analog side above 100 and if so,what did you find,how high did you scan?
10 years ago or so a friend of mine said he had a 1000 channel SONY CABLE READY TV and he scanned above 100 all the way and he found some interesting things!
140 - Test pattern
And when he hit the 800s he heard music on about 30 or so of them.......
Has anyone else ever explored the analog side above 100 and if so,what did you find,how high did you scan?
Re: Interesting......
What country is this? This can't be the US. In order for 1000 analog channels to exist, a cable company would need at least 6 GHz of bandwidth. I don't the CATV standards address anything above channel 139.
Some cable companies hide a monitoring graph or the EAS channel in the 100+ areas.
The Dude said:
What country is this? This can't be the US. In order for 1000 analog channels to exist, a cable company would need at least 6 GHz of bandwidth. I don't the CATV standards address anything above channel 139.
Some cable companies hide a monitoring graph or the EAS channel in the 100+ areas.
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kenrayc
Guest
Sorry Dude this so called 1000 channel Analog tv doesn't exist ,I don't know what your friend was smoking.Now the new digital cable tuners in the new tvs have over 1000 channel capability the tuner go to 125 ,but each sub channel can go as high as 99, example RTN KAIL 7.2 on my tv cable tuner is 104.48.
K
kenrayc
Guest
Here's a interesting thing I scanned my HDTVs cable band and it detected 489 channels but only 70 work the oters say this channel is scrambled. on some channel it would be running a Pay per view movie for short period of time then it would quit suddenly same way with shows such as CSI on ON DEMAND would pop up for a few minutes then quit these were on random channel for example it happened on ch 79.27. Has anyone experience this?
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