Editing Cable television (section)

=== In the United States ===
{{Main|Cable television in the United States}}
{{Summary style|section=yes|date=October 2023}}
Cable television<ref>{{Cite web |title=History of Cable – CCTA |url=https://calcable.org/learn/history-of-cable/ |access-date=2021-11-12 |language=en-US |archive-date=2020-09-19 |archive-url=https://web.archive.org/web/20200919050329/https://calcable.org/learn/history-of-cable/ |url-status=dead }}</ref> began in the United States as a commercial business in 1950s.

The early systems simply received weak ([[broadcast]]) channels, amplified them, and sent them over unshielded wires to the subscribers, limited to a community or to adjacent communities. The receiving antenna would be taller than any individual subscriber could afford, thus bringing in stronger signals; in hilly or mountainous terrain it would be placed at a high elevation.

At the outset, cable systems only served smaller communities without television stations of their own, and which could not easily receive signals from stations in cities because of distance or hilly terrain. In Canada, however, communities with their own signals were fertile cable markets, as viewers wanted to receive American signals. Rarely, as in the college town of [[Alfred, New York]], U.S. cable systems retransmitted Canadian channels.

Although early ([[VHF]]) television receivers could receive 12 channels (2–13), the maximum number of channels that could be broadcast in one city was 7: channels 2, 4, either 5 or 6, 7, 9, 11 and 13, as receivers at the time were unable to receive strong (local) signals on adjacent channels without distortion. (There were frequency gaps between 4 and 5, and between 6 and 7, which allowed both to be used in the same city).

As equipment improved, all twelve channels could be utilized, except where a local VHF television station broadcast. Local broadcast channels were not usable for signals deemed to be a priority, but technology allowed low-priority signals to be placed on such channels by synchronizing their [[blanking interval]]s. TVs were unable to reconcile these blanking intervals and the slight changes  due to travel through a medium, causing [[Ghosting (television)|ghosting]]. The bandwidth of the amplifiers also was limited, meaning frequencies over 250&nbsp;MHz were difficult to transmit to distant portions of the coaxial network, and UHF channels could not be used at all. To expand beyond 12 channels, non-standard ''midband'' channels had to be used, located between the FM band and Channel 7, or ''superband'' beyond Channel 13 up to about 300&nbsp;MHz; these channels initially were only accessible using separate tuner boxes that sent the chosen channel into the TV set on Channel 2, 3 or 4.{{Citation needed|date=November 2017}} Initially, UHF broadcast stations were at a disadvantage because the standard TV sets in use at the time were unable to receive their channels. With the passage of the [[All-Channel Receiver Act]] in 1964, all new television sets were required to include a UHF tuner, nonetheless, it would still take a few years for UHF stations to become competitive.

Before being added to the cable box itself, these midband channels were used for early incarnations of [[pay TV]], e.g. The [[Z Channel]] (Los Angeles) and [[HBO]] but transmitted in the clear i.e. not scrambled as standard TV sets of the period could not pick up the signal nor could the average consumer ''de-tune'' the normal stations to be able to receive it.

Once tuners that could receive select mid-band and super-band channels began to be incorporated into standard television sets, broadcasters were forced to either install scrambling circuitry or move these signals further out of the range of reception for early cable-ready TVs and VCRs. However, once consumer sets had the ability to receive all 181 FCC allocated channels, premium broadcasters were left with no choice but to scramble.

The descrambling circuitry was often published in electronics hobby magazines such as ''[[Popular Science]]'' and ''[[Popular Electronics]]'' allowing anybody with anything more than a rudimentary knowledge of broadcast electronics to be able to build their own and receive the programming without cost.

Later, the cable operators began to carry [[FM radio]] stations, and encouraged subscribers to connect their FM stereo sets to cable. Before [[Multichannel television sound|stereo and bilingual TV sound]] became common, Pay-TV channel sound was added to the FM stereo cable line-ups. About this time, operators expanded beyond the 12-channel dial to use the ''midband'' and ''superband'' VHF channels adjacent to the ''high band'' 7–13 of [[North American television frequencies]]. Some operators as in [[Cornwall, Ontario]], used a dual distribution network with Channels 2–13 on each of the two cables.

During the 1980s, United States regulations not unlike [[public, educational, and government access]] (PEG) created the beginning of cable-originated [[live television]] programming. As cable penetration increased, numerous cable-only TV stations were launched, many with their own news bureaus that could provide more immediate and more localized content than that provided by the nearest network newscast.

Such stations may use similar on-air branding as that used by the nearby broadcast network affiliate, but the fact that these stations do not broadcast over the air and are not regulated by the FCC, their call signs are meaningless. These stations evolved partially into today's over-the-air digital subchannels, where a main broadcast TV station e.g. NBC 37* would – in the case of no local CBS or ABC station being available – rebroadcast the programming from a nearby affiliate but fill in with its own news and other community programming to suit its own locale. Many live [[local program]]s with local interests were subsequently created all over the United States in most major [[television market]]s in the early 1980s.

This evolved into today's many cable-only broadcasts of diverse programming, including cable-only produced [[television movie]]s and [[miniseries]]. Cable [[specialty channel]]s, starting with channels oriented to show movies and large sporting or performance events, diversified further, and [[narrowcasting]] became common.  By the late 1980s, cable-only signals outnumbered broadcast signals on cable systems, some of which by this time had expanded beyond 35 channels. By the mid-1980s in Canada, cable operators were allowed by the regulators to enter into distribution contracts with cable networks on their own.

By the 1990s, tiers became common, with customers able to subscribe to different tiers to obtain different selections of additional channels above the basic selection. By subscribing to additional tiers, customers could get specialty channels, movie channels, and foreign channels. Large cable companies used addressable descramblers to limit access to [[premium channel]]s for customers not subscribing to higher tiers, however the above magazines often published workarounds for that technology as well.

During the 1990s, the pressure to accommodate the growing array of offerings resulted in digital transmission that made more efficient use of the VHF signal capacity; fibre optics was common to carry signals into areas near the home, where coax could carry higher frequencies over the short remaining distance. Although for a time in the 1980s and 1990s, television receivers and VCRs were equipped to receive the mid-band and super-band channels. Because the descrambling circuitry was for a time present in these tuners, depriving the cable operator of much of their revenue, such [[cable-ready]] tuners are rarely used now – requiring a return to the [[set-top box]]es used from the 1970s onward.

The [[digital television transition in the United States]] has put all signals, broadcast and cable, into digital form, rendering analog cable television service a rarity, found in an ever-dwindling number of markets. Analog television sets are accommodated, their tuners mostly obsolete and dependent entirely on the set-top box.