LANC ( Logic Application Control Bus System or Local Application Control Bus System ), also known as Control-L is a hardware and software communication protocol invented by Sony that synchronizes cameras .
121-517: The LANC terminal on Sony and other manufacturers' camcorders lets accessories, such as tripods with a control handle, control the camera over a cable connected to the LANC port instead of using buttons on the camera. It is also available on many still cameras, where it is called ACC (the Sony DSC-xxxx series of cameras). The bi-directional protocol is made up of 8 (8-bit) bytes, usually clocked by
242-480: A 405-line field-sequential color television standard in October 1950, which was developed by CBS . The CBS system was incompatible with existing black-and-white receivers. It used a rotating color wheel, reduced the number of scan lines from 525 to 405, and increased the field rate from 60 to 144, but had an effective frame rate of only 24 frames per second. Legal action by rival RCA kept commercial use of
363-440: A frame rate of 30 frames (images) per second, consisting of two interlaced fields per frame at 262.5 lines per field and 60 fields per second. Other standards in the final recommendation were an aspect ratio of 4:3, and frequency modulation (FM) for the sound signal (which was quite new at the time). In January 1950, the committee was reconstituted to standardize color television . The FCC had briefly approved
484-591: A natural monopoly . The FCC controlled telephone rates and imposed other restrictions under Title II to limit the profits of AT&T and ensure nondiscriminatory pricing. In the 1960s, the FCC began allowing other long-distance companies, namely MCI, to offer specialized services. In the 1970s, the FCC allowed other companies to expand offerings to the public. A lawsuit in 1982 led by the Justice Department after AT&T underpriced other companies, resulted in
605-549: A "chief" that is appointed by the chair of the commission. Bureaus process applications for licenses and other filings, analyze complaints, conduct investigations, develop and implement regulations, and participate in hearings . The FCC has twelve staff offices. The FCC's offices provide support services to the bureaus. The FCC leases space in the Sentinel Square III building in northeast Washington, D.C. Prior to moving to its new headquarters in October 2020,
726-537: A color subcarrier of precisely 315/88 MHz (usually described as 3.579545 MHz±10 Hz). The precise frequency was chosen so that horizontal line-rate modulation components of the chrominance signal fall exactly in between the horizontal line-rate modulation components of the luminance signal, such that the chrominance signal could easily be filtered out of the luminance signal on new television sets, and that it would be minimally visible in existing televisions. Due to limitations of frequency divider circuits at
847-457: A color image. When a transmitter broadcasts an NTSC signal, it amplitude-modulates a radio-frequency carrier with the NTSC signal just described, while it frequency-modulates a carrier 4.5 MHz higher with the audio signal. If non-linear distortion happens to the broadcast signal, the 3.579545 MHz color carrier may beat with the sound carrier to produce a dot pattern on the screen. To make
968-528: A consequence, the ATSC digital television standard states that for 480i signals, SMPTE C colorimetry should be assumed unless colorimetric data is included in the transport stream. Japanese NTSC never changed primaries and whitepoint to SMPTE C, continuing to use the 1953 NTSC primaries and whitepoint. Both the PAL and SECAM systems used the original 1953 NTSC colorimetry as well until 1970; unlike NTSC, however,
1089-421: A digital shorthand to System M. The so-called NTSC-Film standard has a digital standard resolution of 720 × 480 pixel for DVD-Videos , 480 × 480 pixel for Super Video CDs (SVCD, Aspect Ratio: 4:3) and 352 × 240 pixel for Video CDs (VCD). The digital video (DV) camcorder format that is equivalent to NTSC is 720 × 480 pixels. The digital television (DTV) equivalent
1210-493: A higher vertical resolution, but a lower temporal resolution of 25 frames or 50 fields per second. The NTSC field refresh frequency in the black-and-white system originally exactly matched the nominal 60 Hz frequency of alternating current power used in the United States. Matching the field refresh rate to the power source avoided intermodulation (also called beating ), which produces rolling bars on
1331-480: A home-made adapter cable or a pre-made cable by Sony Part# J-6082-535-A. Sony RM-AV2 Remote Commander is an example of a LANC controller that plugs into the Sony 10-pin multi-A/V remote terminal jack. Starting with the 2015 model year, Sony has switched to a special 15 pin multiport connector that looks similar to a USB connector. However, it has 15 pins inside the connector, where a USB connection has 5. Currently, only
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#17327795575861452-480: A minimum of eight cycles of the unmodulated (pure original) color subcarrier. The TV receiver has a local oscillator, which is synchronized with these color bursts to create a reference signal. Combining this reference phase signal with the chrominance signal allows the recovery of the I ′ {\displaystyle I^{\prime }} and Q ′ {\displaystyle Q^{\prime }} signals, which in conjunction with
1573-432: A network could demand any time it wanted from a Network affiliate . The second concerned artist bureaus. The networks served as both agents and employers of artists, which was a conflict of interest the report rectified. In assigning television stations to various cities after World War II , the FCC found that it placed many stations too close to each other, resulting in interference. At the same time, it became clear that
1694-705: A new Federal Communications Commission, including in it also the telecommunications jurisdiction previously handled by the Interstate Commerce Commission. Title II of the Communications Act focused on telecommunications using many concepts borrowed from railroad legislation and Title III contained provisions very similar to the Radio Act of 1927 . The initial organization of the FCC was effected July 17, 1934, in three divisions, Broadcasting, Telegraph, and Telephone. Each division
1815-428: A process called QAM . The I ′ Q ′ {\displaystyle I^{\prime }Q^{\prime }} color space is rotated relative to the difference signal color space, such that orange-blue color information (which the human eye is most sensitive to) is transmitted on the I ′ {\displaystyle I^{\prime }} signal at 1.3 MHz bandwidth, while
1936-465: A program using the NTSC "compatible color" system was an episode of NBC's Kukla, Fran and Ollie on August 30, 1953, although it was viewable in color only at the network's headquarters. The first nationwide viewing of NTSC color came on the following January 1 with the coast-to-coast broadcast of the Tournament of Roses Parade , viewable on prototype color receivers at special presentations across
2057-410: A situation he found "perplexing". These efforts later were documented in a 2015 Harvard Case Study. In 2017, Christine Calvosa replaced Bray as the acting CIO of FCC. On January 4, 2023, the FCC voted unanimously to create a newly formed Space Bureau and Office of International Affairs within the agency, replacing the existing International Bureau. FCC chairwoman Jessica Rosenworcel explained that
2178-475: A wideband receiver. The main audio carrier is 4.5 MHz above the video carrier, making it 250 kHz below the top of the channel. Sometimes a channel may contain an MTS signal, which offers more than one audio signal by adding one or two subcarriers on the audio signal, each synchronized to a multiple of the line frequency. This is normally the case when stereo audio and/or second audio program signals are used. The same extensions are used in ATSC , where
2299-488: Is 3.579545 MHz above the video carrier, and is quadrature-amplitude-modulated with a suppressed carrier. The audio signal is frequency-modulated , like the audio signals broadcast by FM radio stations in the 88–108 MHz band, but with a 25 kHz maximum frequency deviation , as opposed to 75 kHz as is used on the FM band , making analog television audio signals sound quieter than FM radio signals as received on
2420-531: Is 704 × 480 pixels. The National Television System Committee was established in 1940 by the United States Federal Communications Commission (FCC) to resolve the conflicts between companies over the introduction of a nationwide analog television system in the United States. In March 1941, the committee issued a technical standard for black-and-white television that built upon a 1936 recommendation made by
2541-401: Is added to the composite baseband signal (video plus audio and data subcarriers) before modulation. This limits the satellite downlink power spectral density in case the video signal is lost. Otherwise the satellite might transmit all of its power on a single frequency, interfering with terrestrial microwave links in the same frequency band. In half transponder mode, the frequency deviation of
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#17327795575862662-482: Is an independent agency of the United States government that regulates communications by radio , television , wire, satellite , and cable across the United States. The FCC maintains jurisdiction over the areas of broadband access , fair competition , radio frequency use, media responsibility, public safety, and homeland security . The FCC was formed by the Communications Act of 1934 to replace
2783-411: Is composed of two fields, each consisting of 262.5 scan lines, for a total of 525 scan lines. The visible raster is made up of 486 scan lines. The later digital standard, Rec. 601 , only uses 480 of these lines for visible raster. The remainder (the vertical blanking interval ) allow for vertical synchronization and retrace. This blanking interval was originally designed to simply blank
2904-418: Is designed to excite only the corresponding red, green, or blue phosphor dots. TV sets with digital circuitry use sampling techniques to process the signals but the result is the same. For both analog and digital sets processing an analog NTSC signal, the original three color signals are transmitted using three discrete signals (Y, I and Q) and then recovered as three separate colors (R, G, and B) and presented as
3025-701: Is duplicated and then the resulting stream is interlaced. Film shot for NTSC television at 24 frames per second has traditionally been accelerated by 1/24 (to about 104.17% of normal speed) for transmission in regions that use 25-fps television standards. This increase in picture speed has traditionally been accompanied by a similar increase in the pitch and tempo of the audio. More recently, frame-blending has been used to convert 24 FPS video to 25 FPS without altering its speed. Film shot for television in regions that use 25-fps television standards can be handled in either of two ways: Because both film speeds have been used in 25-fps regions, viewers can face confusion about
3146-556: Is funded entirely by regulatory fees. It has an estimated fiscal-2022 budget of US $ 388 million. It has 1,482 federal employees as of July 2020. The FCC's mission, specified in Section One of the Communications Act of 1934 and amended by the Telecommunications Act of 1996 (amendment to 47 U.S.C. §151), is to "make available so far as possible, to all the people of the United States, without discrimination on
3267-443: Is severely limited, analog video transmission through satellites differs from terrestrial TV transmission. AM is a linear modulation method, so a given demodulated signal-to-noise ratio (SNR) requires an equally high received RF SNR. The SNR of studio quality video is over 50 dB, so AM would require prohibitively high powers and/or large antennas. Wideband FM is used instead to trade RF bandwidth for reduced power. Increasing
3388-408: Is the first American standard for analog television , published and adopted in 1941. In 1961, it was assigned the designation System M . It is also known as EIA standard 170. In 1953, a second NTSC standard was adopted, which allowed for color television broadcast compatible with the existing stock of black-and-white receivers. It is one of three major color formats for analog television,
3509-628: Is transmitted for two video fields (lasting 1 video frame). Two film frames are thus transmitted in five video fields, for an average of 2 + 1 ⁄ 2 video fields per film frame. The average frame rate is thus 60 ÷ 2.5 = 24 frames per second, so the average film speed is nominally exactly what it should be. (In reality, over the course of an hour of real time, 215,827.2 video fields are displayed, representing 86,330.88 frames of film, while in an hour of true 24-fps film projection, exactly 86,400 frames are shown: thus, 29.97-fps NTSC transmission of 24-fps film runs at 99.92% of
3630-410: The Q ′ {\displaystyle Q^{\prime }} signal encodes purple-green color information at 0.4 MHz bandwidth; this allows the chrominance signal to use less overall bandwidth without noticeable color degradation. The two signals each amplitude modulate 3.58 MHz carriers which are 90 degrees out of phase with each other and the result added together but with
3751-516: The Y ′ {\displaystyle Y^{\prime }} signal, is reconstructed to the individual R ′ G ′ B ′ {\displaystyle R^{\prime }G^{\prime }B^{\prime }} signals, that are then sent to the CRT to form the image. In CRT televisions, the NTSC signal is turned into three color signals: red, green, and blue, each controlling an electron gun that
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3872-464: The Americas (except Argentina , Brazil , Paraguay , and Uruguay ), Myanmar , South Korea , Taiwan , Philippines , Japan , and some Pacific Islands nations and territories (see map). Since the introduction of digital sources (ex: DVD) the term NTSC has been used to refer to digital formats with number of active lines between 480 and 487 having 30 or 29.97 frames per second rate, serving as
3993-553: The Americas and Japan . With the advent of digital television , analog broadcasts were largely phased out. Most US NTSC broadcasters were required by the FCC to shut down their analog transmitters by February 17, 2009, however this was later moved to June 12, 2009. Low-power stations , Class A stations and translators were required to shut down by 2015, although an FCC extension allowed some of those stations operating on Channel 6 to operate until July 13, 2021. The remaining Canadian analog TV transmitters, in markets not subject to
4114-711: The Broadcast Decency Enforcement Act of 2005 sponsored by then-Senator Sam Brownback , a former broadcaster himself, and endorsed by Congressman Fred Upton of Michigan who authored a similar bill in the United States House of Representatives . The new law stiffens the penalties for each violation of the Act. The Federal Communications Commission will be able to impose fines in the amount of $ 325,000 for each violation by each station that violates decency standards. The legislation raised
4235-504: The United States Senate for five-year terms, except when filling an unexpired term. The U.S. president designates one of the commissioners to serve as chairman. No more than three commissioners may be members of the same political party . None of them may have a financial interest in any FCC-related business. Commissioners may continue serving until the appointment of their replacements. However, they may not serve beyond
4356-494: The breakup of the Bell System from AT&T. Beginning in 1984, the FCC implemented a new goal that all long-distance companies had equal access to the local phone companies' customers. Effective January 1, 1984, the Bell System's many member-companies were variously merged into seven independent "Regional Holding Companies", also known as Regional Bell Operating Companies (RBOCs), or "Baby Bells". This divestiture reduced
4477-497: The carriers themselves being suppressed . The result can be viewed as a single sine wave with varying phase relative to a reference carrier and with varying amplitude. The varying phase represents the instantaneous color hue captured by a TV camera, and the amplitude represents the instantaneous color saturation . The 3.579545 MHz subcarrier is then added to the Luminance to form the composite color signal which modulates
4598-457: The 1960s All-Channel Receiver Act ), to make UHF viable against entrenched VHF stations. In markets where there were no VHF stations and UHF was the only TV service available, UHF survived. In other markets, which were too small to financially support a television station, too close to VHF outlets in nearby cities, or where UHF was forced to compete with more than one well-established VHF station, UHF had little chance for success. Denver had been
4719-562: The ATSC digital carrier is broadcast at 0.31 MHz above the lower bound of the channel. "Setup" is a 54 mV (7.5 IRE ) voltage offset between the "black" and "blanking" levels. It is unique to NTSC. CVBS stands for Color, Video, Blanking, and Sync. The following table shows the values for the basic RGB colors, encoded in NTSC There is a large difference in frame rate between film, which runs at 24 frames per second, and
4840-762: The Cable Communications Policy Act of 1984, and made substantial modifications to Title VI in the Cable Television and Consumer Protection and Competition Act of 1992. Further modifications to promote cross-modal competition (telephone, video, etc.) were made in the Telecommunications Act of 1996, leading to the current regulatory structure. Broadcast television and radio stations are subject to FCC regulations including restrictions against indecency or obscenity. The Supreme Court has repeatedly held, beginning soon after
4961-902: The European Broadcasting Union (EBU) rejected color correction in receivers and studio monitors that year and instead explicitly called for all equipment to directly encode signals for the "EBU" colorimetric values. In reference to the gamuts shown on the CIE chromaticity diagram (above), the variations between the different colorimetries can result in significant visual differences. To adjust for proper viewing requires gamut mapping via LUTs or additional color grading . SMPTE Recommended Practice RP 167-1995 refers to such an automatic correction as an "NTSC corrective display matrix." For instance, material prepared for 1953 NTSC may look desaturated when displayed on SMPTE C or ATSC/ BT.709 displays, and may also exhibit noticeable hue shifts. On
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5082-522: The FCC a legal basis for imposing net neutrality rules (see below), after earlier attempts to impose such rules on an "information service" had been overturned in court. In 2005, the FCC formally established the following principles: To encourage broadband deployment and preserve and promote the open and interconnected nature of the public Internet, Consumers are entitled to access the lawful Internet content of their choice; Consumers are entitled to run applications and use services of their choice, subject to
5203-587: The FCC in the newly created post of associate general counsel/chief diversity officer. Numerous controversies have surrounded the city of license concept as the internet has made it possible to broadcast a single signal to every owned station in the nation at once, particularly when Clear Channel, now IHeartMedia , became the largest FM broadcasting corporation in the US after the Telecommunications Act of 1996 became law - owning over 1,200 stations at its peak. As part of its license to buy more radio stations, Clear Channel
5324-437: The FCC indicated that the public largely believed that the severe consolidation of media ownership had resulted in harm to diversity, localism, and competition in media, and was harmful to the public interest. David A. Bray joined the commission in 2013 as chief information officer and quickly announced goals of modernizing the FCC's legacy information technology (IT) systems, citing 200 different systems for only 1750 people
5445-563: The FCC leased space in the Portals building in southwest Washington, D.C. Construction of the Portals building was scheduled to begin on March 1, 1996. In January 1996, the General Services Administration signed a lease with the building's owners, agreeing to let the FCC lease 450,000 sq ft (42,000 m ) of space in Portals for 20 years, at a cost of $ 17.3 million per year in 1996 dollars. Prior to
5566-403: The FCC said that nearly 55 million Americans did not have access to broadband capable of delivering high-quality voice, data, graphics and video offerings. On February 26, 2015, the FCC reclassified broadband Internet access as a telecommunications service, thus subjecting it to Title II regulation, although several exemptions were also created. The reclassification was done in order to give
5687-459: The FCC's re-allocation map of stations did not come until April 1952, with July 1, 1952, as the official beginning of licensing new stations. Other FCC actions hurt the fledgling DuMont and ABC networks. American Telephone and Telegraph (AT&T) forced television coaxial cable users to rent additional radio long lines , discriminating against DuMont, which had no radio network operation. DuMont and ABC protested AT&T's television policies to
5808-514: The FCC, which regulated AT&T's long-line charges, but the commission took no action. The result was that financially marginal DuMont was spending as much in long-line charge as CBS or NBC while using only about 10 to 15 percent of the time and mileage of either larger network. The FCC's "Sixth Report & Order" ended the Freeze. It took five years for the US to grow from 108 stations to more than 550. New stations came on line slowly, only five by
5929-460: The Internet, cable services and wireless services has raised questions whether new legislative initiatives are needed as to competition in what has come to be called 'broadband' services. Congress has monitored developments but as of 2009 has not undertaken a major revision of applicable regulation. The Local Community Radio Act in the 111th Congress has gotten out of committee and will go before
6050-481: The NTSC color standard, which was cooperatively developed by several companies, including RCA and Philco. In December 1953, the FCC unanimously approved what is now called the NTSC color television standard (later defined as RS-170a). The compatible color standard retained full backward compatibility with then-existing black-and-white television sets. Color information was added to the black-and-white image by introducing
6171-485: The NTSC standard, as well as those using other analog television standards , have switched to, or are in process of switching to, newer digital television standards, with there being at least four different standards in use around the world. North America, parts of Central America , and South Korea are adopting or have adopted the ATSC standards, while other countries, such as Japan , are adopting or have adopted other standards instead of ATSC. After nearly 70 years,
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#17327795575866292-402: The NTSC standard, which runs at approximately 29.97 (10 MHz×63/88/455/525) frames per second. In regions that use 25-fps television and video standards, this difference can be overcome by speed-up . For 30-fps standards, a process called " 3:2 pulldown " is used. One film frame is transmitted for three video fields (lasting 1 + 1 ⁄ 2 video frames), and the next frame
6413-567: The Portals, the FCC had space in six buildings at and around 19th Street NW and M Street NW. The FCC first solicited bids for a new headquarters complex in 1989. In 1991 the GSA selected the Portals site. The FCC had wanted to move into a more expensive area along Pennsylvania Avenue . In 1934, Congress passed the Communications Act , which abolished the Federal Radio Commission and transferred jurisdiction over radio licensing to
6534-519: The Radio Manufacturers Association (RMA). Technical advancements of the vestigial side band technique allowed for the opportunity to increase the image resolution. The NTSC selected 525 scan lines as a compromise between RCA 's 441-scan line standard (already being used by RCA's NBC TV network) and Philco 's and DuMont 's desire to increase the number of scan lines to between 605 and 800. The standard recommended
6655-566: The Sony VPR-RM1 controller works with Sony camcorders from 2015 and newer. Sony "Control-S" is a similar interface, but is uni-directional, providing control-only, and not feedback from the controlled device. Panasonic Control-M is a similar 5-pin mini-DIN bi-directional interface and protocol with a different implementation. This video technology article is a stub . You can help Misplaced Pages by expanding it . NTSC NTSC (from National Television System Committee )
6776-492: The United States accelerated an already ongoing shift in the FCC towards a decidedly more market-oriented stance. A number of regulations felt to be outdated were removed, most controversially the Fairness Doctrine in 1987. In terms of indecency fines, there was no action taken by the FCC on the case FCC v. Pacifica until 1987, about ten years after the landmark United States Supreme Court decision that defined
6897-546: The air and through cable, but also in the home-video market, on both tape and disc, including laser disc and DVD . In digital television and video, which are replacing their analog predecessors, single standards that can accommodate a wider range of frame rates still show the limits of analog regional standards. The initial version of the ATSC standard, for example, allowed frame rates of 23.976, 24, 29.97, 30, 59.94, 60, 119.88 and 120 frames per second, but not 25 and 50. Modern ATSC allows 25 and 50 FPS. Because satellite power
7018-420: The audio subcarrier frequency or lower the line frequency. Raising the audio subcarrier frequency would prevent existing (black and white) receivers from properly tuning in the audio signal. Lowering the line frequency is comparatively innocuous, because the horizontal and vertical synchronization information in the NTSC signal allows a receiver to tolerate a substantial amount of variation in the line frequency. So
7139-422: The basis of race, color, religion, national origin, or sex, rapid, efficient, nationwide, and world-wide wire and radio communication services with adequate facilities at reasonable charges." The act furthermore provides that the FCC was created "for the purpose of the national defense" and "for the purpose of promoting safety of life and property through the use of wire and radio communications." Consistent with
7260-426: The blue difference signal is B ′ − Y ′ {\displaystyle B^{\prime }-Y^{\prime }} . These difference signals are then used to derive two new color signals known as I ′ {\displaystyle I^{\prime }} (in-phase) and Q ′ {\displaystyle Q^{\prime }} (in quadrature) in
7381-572: The book value of AT&T by approximately 70%. The FCC initially exempted "information services" such as broadband Internet access from regulation under Title II. The FCC held that information services were distinct from telecommunications services that are subject to common carrier regulation. However, Section 706 of the Telecommunications Act of 1996 required the FCC to help accelerate deployment of "advanced telecommunications capability" which included high-quality voice, data, graphics, and video, and to regularly assess its availability. In August 2015,
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#17327795575867502-406: The camera at 9600 bit/s. Each frame of bytes occurs in sync with the beginning of each video frame ( NTSC or PAL ). The physical connector is either a 5-pin mini-DIN connector and jack or a 2.5mm 3-conductor phone jack and plug ( TRS connector ). In newer Sony digital Handycam camcorders with 10-pin multi-A/V remote terminal jacks, LANC is available, but not directly accessible without making
7623-448: The camera shutter from the video signal itself. The actual figure of 525 lines was chosen as a consequence of the limitations of the vacuum-tube-based technologies of the day. In early TV systems, a master voltage-controlled oscillator was run at twice the horizontal line frequency, and this frequency was divided down by the number of lines used (in this case 525) to give the field frequency (60 Hz in this case). This frequency
7744-601: The channel bandwidth from 6 to 36 MHz allows a RF SNR of only 10 dB or less. The wider noise bandwidth reduces this 40 dB power saving by 36 MHz / 6 MHz = 8 dB for a substantial net reduction of 32 dB. Sound is on an FM subcarrier as in terrestrial transmission, but frequencies above 4.5 MHz are used to reduce aural/visual interference. 6.8, 5.8 and 6.2 MHz are commonly used. Stereo can be multiplex, discrete, or matrix and unrelated audio and data signals may be placed on additional subcarriers. A triangular 60 Hz energy dispersal waveform
7865-525: The chrominance signal. (Another way this is often stated is that the color subcarrier frequency is an odd multiple of half the line frequency.) They then chose to make the audio subcarrier frequency an integer multiple of the line frequency to minimize visible (intermodulation) interference between the audio signal and the chrominance signal. The original black-and-white standard, with its 15,750 Hz line frequency and 4.5 MHz audio subcarrier, does not meet these requirements, so designers had to either raise
7986-444: The commission in 1934 comprised the following seven members: The complete list of commissioners is available on the FCC website. Frieda B. Hennock (D-NY) was the first female commissioner of the FCC in 1948. The FCC regulates broadcast stations, repeater stations as well as commercial broadcasting operators who operate and repair certain radiotelephone , radio and television stations. Broadcast licenses are to be renewed if
8107-570: The composite baseband signal is reduced to 18 MHz to allow another signal in the other half of the 36 MHz transponder. This reduces the FM benefit somewhat, and the recovered SNRs are further reduced because the combined signal power must be "backed off" to avoid intermodulation distortion in the satellite transponder. A single FM signal is constant amplitude, so it can saturate a transponder without distortion. Federal Communications Commission The Federal Communications Commission ( FCC )
8228-414: The conversion, Congress established a federally sponsored DTV Converter Box Coupon Program for two free converters per household. The FCC regulates telecommunications services under Title II of the Communications Act of 1934. Title II imposes common carrier regulation under which carriers offering their services to the general public must provide services to all customers and may not discriminate based on
8349-571: The country. The first color NTSC television camera was the RCA TK-40 , used for experimental broadcasts in 1953; an improved version, the TK-40A, introduced in March 1954, was the first commercially available color television camera. Later that year, the improved TK-41 became the standard camera used throughout much of the 1960s. The NTSC standard has been adopted by other countries, including some in
8470-427: The designated VHF channels, 2 through 13, were inadequate for nationwide television service. As a result, the FCC stopped giving out construction permits for new licenses in October 1948, under the direction of Chairman Rosel H. Hyde . Most expected this "Freeze" to last six months, but as the allocation of channels to the emerging UHF technology and the eagerly awaited possibilities of color television were debated,
8591-480: The display, etc. Over its history, NTSC color had two distinctly defined colorimetries, shown on the accompanying chromaticity diagram as NTSC 1953 and SMPTE C. Manufacturers introduced a number of variations for technical, economic, marketing, and other reasons. The original 1953 color NTSC specification, still part of the United States Code of Federal Regulations , defined the colorimetric values of
8712-462: The early B&W sets did not do this and chrominance could be seen as a crawling dot pattern in areas of the picture that held saturated colors. To derive the separate signals containing only color information, the difference is determined between each color primary and the summed luma. Thus the red difference signal is R ′ − Y ′ {\displaystyle R^{\prime }-Y^{\prime }} and
8833-405: The electron beam of the receiver's CRT to allow for the simple analog circuits and slow vertical retrace of early TV receivers. However, some of these lines may now contain other data such as closed captioning and vertical interval timecode (VITC). In the complete raster (disregarding half lines due to interlacing ) the even-numbered scan lines (every other line that would be even if counted in
8954-476: The end of 2016. Digital broadcasting allows higher-resolution television , but digital standard definition television continues to use the frame rate and number of lines of resolution established by the analog NTSC standard. NTSC color encoding is used with the System M television signal, which consists of 30 ⁄ 1.001 (approximately 29.97) interlaced frames of video per second . Each frame
9075-421: The end of November 1952. The Sixth Report and Order required some existing television stations to change channels, but only a few existing VHF stations were required to move to UHF, and a handful of VHF channels were deleted altogether in smaller media markets like Peoria , Fresno , Bakersfield and Fort Wayne, Indiana to create markets which were UHF "islands." The report also set aside a number of channels for
9196-413: The end of the next session of Congress following term expiration. In practice, this means that commissioners may serve up to 1 + 1 ⁄ 2 years beyond the official term expiration listed above if no replacement is appointed. This would end on the date that Congress adjourns its annual session, generally no later than noon on January 3. The FCC is organized into seven bureaus, each headed by
9317-489: The end of the digital television transition. After delaying the original deadlines of 2006, 2008, and eventually February 17, 2009, on concerns about elderly and rural folk, on June 12, 2009, all full-power analog terrestrial TV licenses in the U.S. were terminated as part of the DTV transition , leaving terrestrial television available only from digital channels and a few low-power LPTV stations. To help U.S. consumers through
9438-417: The engineers chose the line frequency to be changed for the color standard. In the black-and-white standard, the ratio of audio subcarrier frequency to line frequency is 4.5 MHz ⁄ 15,750 Hz = 285.71. In the color standard, this becomes rounded to the integer 286, which means the color standard's line rate is 4.5 MHz ⁄ 286 ≈ 15,734 Hz. Maintaining
9559-549: The film's normal speed.) Still-framing on playback can display a video frame with fields from two different film frames, so any difference between the frames will appear as a rapid back-and-forth flicker. There can also be noticeable jitter/"stutter" during slow camera pans ( telecine judder ). Film shot specifically for NTSC television is usually taken at 30 (instead of 24) frames per second to avoid 3:2 pulldown. To show 25-fps material (such as European television series and some European movies) on NTSC equipment, every fifth frame
9680-423: The fine ten times over the previous maximum of $ 32,500 per violation. The FCC has established rules limiting the national share of media ownership of broadcast radio or television stations. It has also established cross-ownership rules limiting ownership of a newspaper and broadcast station in the same market, in order to ensure a diversity of viewpoints in each market and serve the needs of each local market. In
9801-598: The first post-Freeze construction permits. KFEL (now KWGN-TV )'s first regular telecast was on July 21, 1952. In 1996, Congress enacted the Telecommunications Act of 1996 , in the wake of the breakup of AT&T resulting from the U.S. Department of Justice's antitrust suit against AT&T. The legislation attempted to create more competition in local telephone service by requiring Incumbent Local Exchange Carriers to provide access to their facilities for Competitive Local Exchange Carriers . This policy has thus far had limited success and much criticism. The development of
9922-435: The house floor with bi-partisan support, and unanimous support of the FCC. By passing the Telecommunications Act of 1996, Congress also eliminated the cap on the number of radio stations any one entity could own nationwide and also substantially loosened local radio station ownership restrictions. Substantial radio consolidation followed. Restrictions on ownership of television stations were also loosened. Public comments to
10043-446: The identity of the customer or the content of the communication. This is similar to and adapted from the regulation of transportation providers (railroad, airline, shipping, etc.) and some public utilities. Wireless carriers providing telecommunications services are also generally subject to Title II regulation except as exempted by the FCC. The FCC regulates interstate telephone services under Title II. The Telecommunications Act of 1996
10164-527: The largest U.S. city without a TV station by 1952. Senator Edwin Johnson (D-Colorado), chair of the Senate's Interstate and Foreign Commerce Committee , had made it his personal mission to make Denver the first post-Freeze station. The senator had pressured the FCC, and proved ultimately successful as the first new station (a VHF station) came on-line a remarkable ten days after the commission formally announced
10285-427: The lower bound of the channel. The video carrier is 1.25 MHz above the lower bound of the channel. Like most AM signals, the video carrier generates two sidebands , one above the carrier and one below. The sidebands are each 4.2 MHz wide. The entire upper sideband is transmitted, but only 1.25 MHz of the lower sideband, known as a vestigial sideband , is transmitted. The color subcarrier, as noted above,
10406-721: The majority of over-the-air NTSC transmissions in the United States ceased on June 12, 2009, and by August 31, 2011, in Canada and most other NTSC markets. The majority of NTSC transmissions ended in Japan on July 24, 2011, with the Japanese prefectures of Iwate , Miyagi , and Fukushima ending the next year. After a pilot program in 2013, most full-power analog stations in Mexico left the air on ten dates in 2015, with some 500 low-power and repeater stations allowed to remain in analog until
10527-466: The mandatory transition in 2011, were scheduled to be shut down by January 14, 2022, under a schedule published by Innovation, Science and Economic Development Canada in 2017; however the scheduled transition dates have already passed for several stations listed that continue to broadcast in analog (e.g. CFJC-TV Kamloops, which has not yet transitioned to digital, is listed as having been required to transition by November 20, 2020). Most countries using
10648-492: The move was done to improve the FCC's "coordination across the federal government" and to "support the 21st-century satellite industry." The decision to establish the Space Bureau was reportedly done to improve the agency's capacity to regulate Satellite Internet access . The new bureau officially launched on April 11, 2023. The commissioners of the FCC are: The initial group of FCC commissioners after establishment of
10769-503: The negative effects of media concentration and consolidation on racial-ethnic diversity in staffing and programming. At these Latino town hall meetings, the issue of the FCC's lax monitoring of obscene and pornographic material in Spanish-language radio and the lack of racial and national-origin diversity among Latino staff in Spanish-language television were other major themes. President Barack Obama appointed Mark Lloyd to
10890-482: The newly emerging field of educational television , which hindered struggling ABC and DuMont 's quest for affiliates in the more desirable markets where VHF channels were reserved for non-commercial use. The Sixth Report and Order also provided for the "intermixture" of VHF and UHF channels in most markets; UHF transmitters in the 1950s were not yet powerful enough, nor receivers sensitive enough (if they included UHF tuners at all - they were not formally required until
11011-559: The nonlinear gamma corrected signals transmitted, the adjustment can only be approximated, introducing both hue and luminance errors for highly saturated colors. Similarly at the broadcaster stage, in 1968–69 the Conrac Corp., working with RCA, defined a set of controlled phosphors for use in broadcast color picture video monitors . This specification survives today as the SMPTE C phosphor specification: As with home receivers, it
11132-473: The objectives of the act as well as the 1999 Government Performance and Results Act (GPRA), the FCC has identified four goals in its 2018–22 Strategic Plan. They are: Closing the Digital Divide, Promoting Innovation, Protecting Consumers & Public Safety, and Reforming the FCC's Processes. The FCC is directed by five commissioners appointed by the president of the United States and confirmed by
11253-515: The only practical method of frequency division was the use of a chain of vacuum tube multivibrators , the overall division ratio being the mathematical product of the division ratios of the chain. Since all the factors of an odd number also have to be odd numbers, it follows that all the dividers in the chain also had to divide by odd numbers, and these had to be relatively small due to the problems of thermal drift with vacuum tube devices. The closest practical sequence to 500 that meets these criteria
11374-419: The original black-and-white system; when color was added to the system, however, the refresh frequency was shifted slightly downward by 0.1%, to approximately 59.94 Hz, to eliminate stationary dot patterns in the difference frequency between the sound and color carriers (as explained below in § Color encoding ). By the time the frame rate changed to accommodate color, it was nearly as easy to trigger
11495-426: The other hand, SMPTE C materials may appear slightly more saturated on BT.709/sRGB displays, or significantly more saturated on P3 displays, if the appropriate gamut mapping is not performed. NTSC uses a luminance - chrominance encoding system, incorporating concepts invented in 1938 by Georges Valensi . Using a separate luminance signal maintained backward compatibility with black-and-white television sets in use at
11616-471: The others being PAL and SECAM . NTSC color is usually associated with the System M; this combination is sometimes called NTSC II. The only other broadcast television system to use NTSC color was the System J . Brazil used System M with PAL color. Vietnam, Cambodia and Laos used System M with SECAM color - Vietnam later started using PAL in the early 1990s. The NTSC/System M standard was used in most of
11737-584: The passage of the Communications Act of 1934, that the inherent scarcity of radio spectrum allows the government to impose some types of content restrictions on broadcast license holders notwithstanding the First Amendment. Cable and satellite providers are also subject to some content regulations under Title VI of the Communications Act such as the prohibition on obscenity, although the limitations are not as restrictive compared to broadcast stations. The 1981 inauguration of Ronald Reagan as President of
11858-407: The place of the original monochrome signal . The color difference information is encoded into the chrominance signal, which carries only the color information. This allows black-and-white receivers to display NTSC color signals by simply ignoring the chrominance signal. Some black-and-white TVs sold in the U.S. after the introduction of color broadcasting in 1953 were designed to filter chroma out, but
11979-473: The power of the FCC over indecent material as applied to broadcasting. After the 1990s had passed, the FCC began to increase its censorship and enforcement of indecency regulations in the early 2000s to include a response to the Janet Jackson " wardrobe malfunction " that occurred during the halftime show of Super Bowl XXXVIII . Then on June 15, 2006, President George W. Bush signed into law
12100-654: The radio regulation functions of the previous Federal Radio Commission . The FCC took over wire communication regulation from the Interstate Commerce Commission . The FCC's mandated jurisdiction covers the 50 states, the District of Columbia , and the territories of the United States . The FCC also provides varied degrees of cooperation, oversight, and leadership for similar communications bodies in other countries in North America. The FCC
12221-650: The report was the breakup of the National Broadcasting Company (NBC), which ultimately led to the creation of the American Broadcasting Company (ABC), but there were two other important points. One was network option time, the culprit here being the Columbia Broadcasting System (CBS). The report limited the amount of time during the day and at what times the networks may broadcast. Previously
12342-400: The resulting pattern less noticeable, designers adjusted the original 15,750 Hz scanline rate down by a factor of 1.001 (0.1%) to match the audio carrier frequency divided by the factor 286, resulting in a field rate of approximately 59.94 Hz. This adjustment ensures that the difference between the sound carrier and the color subcarrier (the most problematic intermodulation product of
12463-441: The same number of scan lines per field (and frame), the lower line rate must yield a lower field rate. Dividing 4500000 ⁄ 286 lines per second by 262.5 lines per field gives approximately 59.94 fields per second. An NTSC television channel as transmitted occupies a total bandwidth of 6 MHz. The actual video signal, which is amplitude-modulated , is transmitted between 500 kHz and 5.45 MHz above
12584-415: The screen. Synchronization of the refresh rate to the power incidentally helped kinescope cameras record early live television broadcasts, as it was very simple to synchronize a film camera to capture one frame of video on each film frame by using the alternating current frequency to set the speed of the synchronous AC motor-drive camera. This, as mentioned, is how the NTSC field refresh frequency worked in
12705-960: The second half of 2006, groups such as the National Hispanic Media Coalition, the National Latino Media Council, the National Association of Hispanic Journalists, the National Institute for Latino Policy , the League of United Latin American Citizens (LULAC) and others held town hall meetings in California, New York and Texas on media diversity as its effects Latinos and minority communities. They documented widespread and deeply felt community concerns about
12826-436: The standard at both the receiver and broadcaster was the source of considerable color variation. To ensure more uniform color reproduction, some manufacturers incorporated color correction circuits into sets, that converted the received signal—encoded for the colorimetric values listed above—adjusting for the actual phosphor characteristics used within the monitor. Since such color correction can not be performed accurately on
12947-435: The station meets the "public interest, convenience, or necessity". The FCC's enforcement powers include fines and broadcast license revocation (see FCC MB Docket 04-232). Burden of proof would be on the complainant in a petition to deny. The FCC first promulgated rules for cable television in 1965, with cable and satellite television now regulated by the FCC under Title VI of the Communications Act. Congress added Title VI in
13068-601: The system as shown in the above table. Early color television receivers, such as the RCA CT-100 , were faithful to this specification (which was based on prevailing motion picture standards), having a larger gamut than most of today's monitors. Their low-efficiency phosphors (notably in the Red) were weak and long-persistent, leaving trails after moving objects. Starting in the late 1950s, picture tube phosphors would sacrifice saturation for increased brightness; this deviation from
13189-591: The system off the air until June 1951, and regular broadcasts only lasted a few months before manufacture of all color television sets was banned by the Office of Defense Mobilization in October, ostensibly due to the Korean War . A variant of the CBS system was later used by NASA to broadcast pictures of astronauts from space. CBS rescinded its system in March 1953, and the FCC replaced it on December 17, 1953, with
13310-658: The time the color standard was promulgated, the color subcarrier frequency was constructed as composite frequency assembled from small integers, in this case 5×7×9/(8×11) MHz. The horizontal line rate was reduced to approximately 15,734 lines per second (3.579545×2/455 MHz = 9/572 MHz) from 15,750 lines per second, and the frame rate was reduced to 30/1.001 ≈ 29.970 frames per second (the horizontal line rate divided by 525 lines/frame) from 30 frames per second. These changes amounted to 0.1 percent and were readily tolerated by then-existing television receivers. The first publicly announced network television broadcast of
13431-491: The time; only color sets would recognize the chroma signal, which was essentially ignored by black and white sets. The red, green, and blue primary color signals ( R ′ G ′ B ′ ) {\displaystyle (R^{\prime }G^{\prime }B^{\prime })} are weighted and summed into a single luma signal, designated Y ′ {\displaystyle Y^{\prime }} (Y prime) which takes
13552-597: The true speed of video and audio, and the pitch of voices, sound effects, and musical performances, in television films from those regions. For example, they may wonder whether the Jeremy Brett series of Sherlock Holmes television films, made in the 1980s and early 1990s, was shot at 24 fps and then transmitted at an artificially fast speed in 25-fps regions, or whether it was shot at 25 fps natively and then slowed to 24 fps for NTSC exhibition. These discrepancies exist not only in television broadcasts over
13673-409: The two carriers) is an odd multiple of half the line rate, which is the necessary condition for the dots on successive lines to be opposite in phase, making them least noticeable. The 59.94 rate is derived from the following calculations. Designers chose to make the chrominance subcarrier frequency an n + 0.5 multiple of the line frequency to minimize interference between the luminance signal and
13794-449: The video signal carrier . 3.58 MHz is often stated as an abbreviation instead of 3.579545 MHz. For a color TV to recover hue information from the color subcarrier, it must have a zero-phase reference to replace the previously suppressed carrier. The NTSC signal includes a short sample of this reference signal, known as the colorburst , located on the back porch of each horizontal synchronization pulse. The color burst consists of
13915-466: The video signal, e.g. {2, 4, 6, ..., 524}) are drawn in the first field, and the odd-numbered (every other line that would be odd if counted in the video signal, e.g. {1, 3, 5, ..., 525}) are drawn in the second field, to yield a flicker-free image at the field refresh frequency of 60 ⁄ 1.001 Hz (approximately 59.94 Hz). For comparison, 625 lines (576 visible) systems, usually used with PAL-B/G and SECAM color, and so have
14036-462: Was 3×5×5×7=525 . (For the same reason, 625-line PAL-B/G and SECAM uses 5×5×5×5 , the old British 405-line system used 3×3×3×3×5 , the French 819-line system used 3×3×7×13 etc.) Colorimetry refers to the specific colorimetric characteristics of the system and its components, including the specific primary colors used, the camera,
14157-441: Was forced to divest all TV stations. To facilitate the adoption of digital television, the FCC issued a second digital TV (DTV) channel to each holder of an analog TV station license. All stations were required to buy and install all new equipment ( transmitters , TV antennas, and even entirely new broadcast towers ), and operate for years on both channels. Each licensee was required to return one of their two channels following
14278-886: Was further recommended that studio monitors incorporate similar color correction circuits so that broadcasters would transmit pictures encoded for the original 1953 colorimetric values, in accordance with FCC standards. In 1987, the Society of Motion Picture and Television Engineers (SMPTE) Committee on Television Technology, Working Group on Studio Monitor Colorimetry, adopted the SMPTE C (Conrac) phosphors for general use in Recommended Practice 145, prompting many manufacturers to modify their camera designs to directly encode for SMPTE C colorimetry without color correction, as approved in SMPTE standard 170M, "Composite Analog Video Signal – NTSC for Studio Applications" (1994). As
14399-560: Was led by two of the seven commissioners, with the FCC chairman being a member of each division. The organizing meeting directed the divisions to meet on July 18, July 19, and July 20, respectively. In 1940, the Federal Communications Commission issued the "Report on Chain Broadcasting " which was led by new FCC chairman James Lawrence Fly (and Telford Taylor as general counsel). The major point in
14520-471: Was the first major legislative reform since the 1934 act and took several steps to de-regulate the telephone market and promote competition in both the local and long-distance marketplace. The important relationship of the FCC and the American Telephone and Telegraph (AT&T) Company evolved over the decades. For many years, the FCC and state officials agreed to regulate the telephone system as
14641-401: Was then compared with the 60 Hz power-line frequency and any discrepancy corrected by adjusting the frequency of the master oscillator. For interlaced scanning, an odd number of lines per frame was required in order to make the vertical retrace distance identical for the odd and even fields, which meant the master oscillator frequency had to be divided down by an odd number. At the time,
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