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Is there a chart that shows the over the air equivalents of cable channels?

The cable interference question got me wondering about where in the frequency spectrum do cable channels fall and what are the over the air equivalents? I know that channels 2 through 13 are the same on cable or over the air, but that there are also some cable channels that are between channels 6 and 7 and others between channels 13 and 14 over the air. I also know that starting at cable channel 65 you can subtract 51 to get the over the air equivalent starting at channel 14, but how far up does that work? (Have I confused everyone totally??? ??? ::) )

Is there a chart that shows how cable channels fall compared to actual over the air frequencies? Thanks! ;D
 
Occasionally, some manuals for TVs from the 1990s used to print something like that. I know cable channel 117 is UHF channel 61 (FOX channel 61 is a local here).
 
It works like this:

2-13 = same as OTA channel #
14-65 = in the gaps between OTA 6-7 and VHF-UHF
65-94 = OTA channels 14-43
95-99 = FM/aircraft band
100-125 = OTA channels 44-69
126-139 = former OTA channels 70-83
 
clichemoth said:
It works like this:

2-13 = same as OTA channel #
14-65 = in the gaps between OTA 6-7 and VHF-UHF
65-94 = OTA channels 14-43
95-99 = FM/aircraft band
100-125 = OTA channels 44-69
126-139 = former OTA channels 70-83

To elaborate, by frequency:

Chs. 2-6 (54-88 MHz) - Same as OTA 2-6
Chs. 95-99 (90-120 MHz)
Chs. 14-22 (120-174 MHz)
Chs. 7-13 (174-216 MHz) - Same as OTA 7-13
Chs. 23-64 (216-468 MHz)
Chs. 65-94 (468-648 MHz) - 2 MHz below OTA 14-43, respectively
Chs. 100-125 (648-804 MHz) - 2 MHz below OTA 44-69, respectively

I've never seen a TV or VCR that tuned Chs. 126-139, but those would be 2 MHz below the old UHF 70-83, respectively, as was stated above.

They could have even resurrected the pre-1948 Channel 1 (44-50 MHz) and even added a Channel 0 (38-44 MHz) if they wanted to. ;D

Most folks here know this already, but if your TV is configured to tune cable channels and you connect a UHF antenna to it, it's possible to receive amateur television on cable channels 57-61 (420-450 MHz).
 
KeithE4 said:
clichemoth said:
It works like this:

2-13 = same as OTA channel #
14-65 = in the gaps between OTA 6-7 and VHF-UHF
65-94 = OTA channels 14-43
95-99 = FM/aircraft band
100-125 = OTA channels 44-69
126-139 = former OTA channels 70-83

To elaborate, by frequency:

Chs. 2-6 (54-88 MHz) - Same as OTA 2-6
Chs. 95-99 (90-120 MHz)
Chs. 14-22 (120-174 MHz)
Chs. 7-13 (174-216 MHz) - Same as OTA 7-13
Chs. 23-64 (216-468 MHz)
Chs. 65-94 (468-648 MHz) - 2 MHz below OTA 14-43, respectively
Chs. 100-125 (648-804 MHz) - 2 MHz below OTA 44-69, respectively

I've never seen a TV or VCR that tuned Chs. 126-139, but those would be 2 MHz below the old UHF 70-83, respectively, as was stated above.

They could have even resurrected the pre-1948 Channel 1 (44-50 MHz) and even added a Channel 0 (38-44 MHz) if they wanted to. ;D

Most folks here know this already, but if your TV is configured to tune cable channels and you connect a UHF antenna to it, it's possible to receive amateur television on cable channels 57-61 (420-450 MHz).

I have seen cable systems that did indeed have channels 0 and 1. However, I believe they were just 100 and 101 remapped to 0 and 1 on the brand of cable boxes the companies used.

Was New York 1 on 1 prior to the advent of digital cable? I know it already existed.
 
Well, I have a Zenith TV from 1989 that, when set to Cable, has a channel 0 and a channel 00. I have wondered what the original purpose of those channels was. I can understand there being a cable channel 1, since the cable company in my area, which was then known as Continental Cablevision, carried Lifetime on channel 1. But I've never understood channels 0 and 00. Anyone here know?
 
Also, don't forget that for a time in the 70s and 80s, some cable in the Midwestern U.S. utilized a different system that was not based on Co-axle cable, but that flat type of cable that used to connect to your UHF antenna. That's why some older TV's have a special setting for 75 Ohms. The alignment might be differnet in that case, but I don't know for sure.
 
Thanks for all the information so far. Now I have another question: What frequencies would the channels on digital tuners (100 and up) fall on? I know that the answers for 100 to 139 might apply, but what about the others? Thanks again! ;D
 
Digital might not use frequencies, but I'm not a techie.

Didn't I see something on these boards that said cable channel 1 uses the gap between 4 and 5 OTA?
 
Morgan Wick said:
Digital might not use frequencies, but I'm not a techie.

All transmissions use "frequencies." Digital or analog doesn't matter - they're just different modes of transmission. I'm not sure exactly how they transmit the digital channels over the cable, but I'll guess each channel uses a much smaller bandwith than the 6 MHz analog (NTSC) channel. Or, they could put 3 or 4 stations in each 6 MHz channel like OTA digital TV. I'm just guessing.

Didn't I see something on these boards that said cable channel 1 uses the gap between 4 and 5 OTA?

Some systems, particularly in the '80s, used "Channel 1" instead of Channel 5, particularly if there was a local station on 5 that interfered with the cable. IIRC, It ran from 72-78 MHz or 74-80 MHz depending on the system. When I lived in suburban Chicago in the mid '80s, the local cable company called that "Channel 54" rather than "Channel 1" and put WMAQ-TV/5 there.
 
Morgan Wick said:
Digital might not use frequencies, but I'm not a techie.

Didn't I see something on these boards that said cable channel 1 uses the gap between 4 and 5 OTA?

I am no engineer, so bear with me. Channel 1 uses the in-between frequencies if it is an HRC or IRC system. Standard cable systems (95-99% of systems) do not have a Channel 1.

Digital uses modulation schemes seperate from analog called "shift keying". It still uses frequencies.
 
Hi everyone:
KeithE4 said:
Morgan Wick said:
Didn't I see something on these boards that said cable channel 1 uses the gap between 4 and 5 OTA?

Some systems, particularly in the '80s, used "Channel 1" instead of Channel 5, particularly if there was a local station on 5 that interfered with the cable. IIRC, It ran from 72-78 MHz or 74-80 MHz depending on the system. When I lived in suburban Chicago in the mid '80s, the local cable company called that "Channel 54" rather than "Channel 1" and put WMAQ-TV/5 there.
Here in Denver (And someone can correct me on the timing of this and clarify things as my memory is a little blurry as to how it all went down), the local cable company (At least TCI, which is the one I was with as we had two in the area at the time. United Artists Cable was the other company) had put HBO2 on Channel 1 even though HBO was on Channel 14.

This was because Showtime was on cable Channel 5 and then-Indie KTVD 20 (This was still the late '80s-early '90s) had just taken over cable channel 3 (USA Network was moved to cable channel 24 where it still is today).

Cheers :D
 
When visiting New York, I discovered that (at least in Manhattan), the "Channel Number" is assigned by a digital box. The hotel's I've stayed in have had Time Warner Manhattan cable, but the channel's on the TV (as well as my VCR) weren't in the "correct" position. NY1 was actually on 10 (without a box) but mapped to 1 on a cable box; likewise WXTV/41 was in the 2-13 range, but on 41 on the cable box (the bar & lobby each had a box that mapped the channels to the assigned number that most folks were familiar with. IIRC, most of the low channels (22 and lower) were OTA channels and/or Public Service and/or community channels - the further you went up on a TV tuner, the "higher" you'd get in cable packages...

Now before anyone yells "It was probably just a satellite system remapped" - they had local Community Access channels, NY1 and Manhattan's Weather channel feed...

Back in the 80s/90s, Fort Worth's cable system mapped KXAS (5) to Channel 1 - the channel cable boxes started out on when turned on - KXAS was on a mid-band channel for cable ready sets, but if you had cable, you pretty much had a box...

Jim

Jim
 
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