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Akio Morita

Akio Morita (盛田 昭夫) was a Japanese entrepreneur and co-founder of Sony along with Masaru Ibuka.

Early life
Akio Morita was born in Nagoya. Morita's family was involved in sake, miso and soy sauce production in the village of Kosugaya (currently a part of Tokoname City) on the western coast of Chita Peninsula in Aichi Prefecture since 1665. He was the oldest of four siblings and his father Kyuzaemon trained him as a child to take over the family business. Akio, however, found his true calling in mathematics and physics, and in 1944 he graduated from Osaka Imperial University with a degree in physics. He was later commissioned as a sub-lieutenant in the Imperial Japanese Navy, and served in World War II. During his service, Morita met his future business partner Masaru Ibuka at a study group for developing infrared-guided bombs (Ke-Go) in the Navy's Wartime Research Committee.

Sony
In September 1945, Ibuka founded a radio repair shop in the bombed out Shirokiya Department Store in Nihonbashi, Tokyo. Morita saw a newspaper article about Ibuka's new venture and, after some correspondence, chose to join him in Tokyo. With funding from Morita's father, they co-founded Tokyo Tsushin Kogyo Kabushiki Kaisha (Tokyo Telecommunications Engineering Corporation, the forerunner of Sony Corporation) in 1946 with about 20 employees and initial capital of ¥190,000.

In 1949, the company developed magnetic recording tape and, in 1950, sold the first tape recorder in Japan. Ibuka was instrumental in securing the licensing of transistor technology from Bell Labs to Sony in the 1950s, thus making Sony one of the first companies to apply transistor technology to non-military uses. In 1957, the company produced a pocket-sized radio (the first to be fully transistorized), and in 1958, Morita and Ibuka decided to rename their company Sony Corporation (derived from "sonus"—Latin for "sound"—and "sonny", a then-common American expression). Morita was an advocate for all the products made by Sony. However, since the radio was slightly too big to fit in a shirt pocket, Morita made his employees wear shirts with slightly larger pockets to give the radio a "pocket sized" appearance.

Morita founded Sony Corporation of America (SONAM, currently abbreviated as SCA) in 1960. In the process, he was struck by the mobility of employees between American companies, which was unheard of in Japan at that time. When he returned to Japan, he encouraged experienced, middle-aged employees of other companies to reevaluate their careers and consider joining Sony. The company filled many positions in this manner, and inspired other Japanese companies to do the same. In 1961, Sony Corporation was the first Japanese company to be listed on the New York Stock Exchange, in the form of American depositary receipts (ADRs).

In March 1968, Morita set up a joint venture in Japan between Sony and CBS Records, with him as president, to manufacture "software" for Sony's hardware.

Morita became president of Sony in 1971, taking over from Ibuka who had served from 1950 to 1971. In 1975, Sony released the first Betamax home videocassette recorder, a year before the VHS format came out.

Ibuka retired in 1976 and Morita was named chairman of the company. In 1979, the Walkman was introduced, making it one of the world's first portable music players and in 1982, Sony launched the world's first compact disc player, the Sony CDP-101, with a compact disc (CD) itself, a new data storage format Sony and Philips co-developed. In that year, a 3.5-inch floppy disk structure was introduced by Sony and it soon became the defacto standard. In 1984, Sony launched the Discman series which extended their Walkman brand to portable CD products.

Under the vision of Morita, the company aggressively expanded into new businesses. Part of its motivation for doing so was the pursuit of "convergence", linking film, music and digital electronics. Twenty years after setting up a joint venture with CBS Records in Japan, Sony bought CBS Records Group which consisted of Columbia Records, Epic Records and other CBS labels. In 1989, they acquired Columbia Pictures Entertainment (Columbia Pictures, TriStar Pictures and others).

Norio Ohga, who had joined the company in the 1950s after sending Morita a letter denouncing the poor quality of the company's tape recorders, succeeded Morita as chief executive officer in 1989.

Morita suffered a cerebral hemorrhage in 1993 while playing tennis and on November 25, 1994, stepped down as Sony chairman to be succeeded by Ohga.

Other affiliations
Morita was vice chairman of the Japan Business Federation (Japan Federation of Economic Organizations), and was a member of the Japan-U.S. Economic Relations Group, also known as the "Wise Men's Group". He helped General Motors with their acquisition of an interest in Isuzu Motors in 1972. He was the third Japanese chairman of the Trilateral Commission. His amateur radio call sign is JP1DPJ.

Publications
In 1966, Morita wrote a book called Gakureki Muyō Ron (学歴無用論, Never Mind School Records), where he stresses that school records are not important to success or one's business skills. In 1986, Morita wrote an autobiography titled Made in Japan. He co-authored the 1991 book The Japan That Can Say No with politician Shintaro Ishihara, where they criticized American business practices and encouraged Japanese to take a more independent role in business and foreign affairs. (Actually, Morita had no intention to criticize American practices at that time.) The book was translated into English and caused controversy in the United States, and Morita later had his chapters removed from the English version and distanced himself from the book.

Awards and honours
In 1972, Morita received the Golden Plate Award of the American Academy of Achievement. Morita was awarded the Albert Medal by the United Kingdom's Royal Society of Arts in 1982, the first Japanese to receive the honor. Two years later, he received the prestigious Legion of Honour, and in 1991, was awarded the First Class Order of the Sacred Treasure from the Emperor of Japan. He was elected to the American Philosophical Society in 1992 and the American Academy of Arts and Sciences in 1993. That same year, he was awarded an honorary British knighthood (KBE). Morita received the International Distinguished Entrepreneur Award from the University of Manitoba in 1987. In 1998, he was the only Asian person on Time magazine's list of the 20 most influential business people of the 20th century as part of their Time 100: The Most Important People of the Century. He was posthumously awarded the Grand Cordon of the Order of the Rising Sun in 1999. In 2003, Anaheim University's Graduate School of Business was renamed the Akio Morita School of Business in his honor. The Morita family's support for the program led to the growth of the Anaheim University Akio Morita School of Business in Tokyo, Japan.

Television commercials

 * American Express (1984)

Death
Morita, who loved to play golf and tennis and to watch movies when rainy, suffered a stroke in 1993, during a game of tennis. The stroke weakened him and left him in a wheelchair. On November 25, 1994, he stepped down as Sony chairman. On October 3, 1999, Morita died of pneumonia at the age of 78 in a Tokyo hospital, where he had been admitted since August 1999.

title: Akio Morita


text:
Anode

An anode is an electrode of a polarized electrical device through which conventional current enters the device. This contrasts with a cathode, an electrode of the device through which conventional current leaves the device. A common mnemonic is ACID, for "anode current into device". The direction of conventional current (the flow of positive charges) in a circuit is opposite to the direction of electron flow, so (negatively charged) electrons flow from the anode of a galvanic cell, into an outside or external circuit connected to the cell. For example, the end of a household battery marked with a "+" is the cathode (while discharging).

In both a galvanic cell and an electrolytic cell, the anode is the electrode at which the oxidation reaction occurs. In a galvanic cell the anode is the wire or plate having excess negative charge as a result of the oxidation reaction. In an electrolytic cell, the anode is the wire or plate upon which excess positive charge is imposed. As a result of this, anions will tend to move towards the anode where they will undergo oxidation.

Historically, the anode of a galvanic cell was also known as the zincode because it was usually composed of zinc.

Charge flow
The terms anode and cathode are not defined by the voltage polarity of electrodes but the direction of current through the electrode. An anode is an electrode of a device through which conventional current (positive charge) flows into the device from an external circuit, while a cathode is an electrode through which conventional current flows out of the device. If the current through the electrodes reverses direction, as occurs for example in a rechargeable battery when it is being charged, the roles of the electrodes as anode and cathode are reversed.

Conventional current depends not only on the direction the charge carriers move, but also the carriers' electric charge. The currents outside the device are usually carried by electrons in a metal conductor. Since electrons have a negative charge, the direction of electron flow is opposite to the direction of conventional current. Consequently, electrons leave the device through the anode and enter the device through the cathode.

The definition of anode and cathode is different for electrical devices such as diodes and vacuum tubes where the electrode naming is fixed and does not depend on the actual charge flow (current). These devices usually allow substantial current flow in one direction but negligible current in the other direction. Therefore, the electrodes are named based on the direction of this "forward" current. In a diode the anode is the terminal through which current enters and the cathode is the terminal through which current leaves, when the diode is forward biased. The names of the electrodes do not change in cases where reverse current flows through the device. Similarly, in a vacuum tube only one electrode can emit electrons into the evacuated tube due to being heated by a filament, so electrons can only enter the device from the external circuit through the heated electrode. Therefore, this electrode is permanently named the cathode, and the electrode through which the electrons exit the tube is named the anode.

Examples
The polarity of voltage on an anode with respect to an associated cathode varies depending on the device type and on its operating mode. In the following examples, the anode is negative in a device that provides power, and positive in a device that consumes power:

In a discharging battery or galvanic cell (diagram on left), the anode is the negative terminal: it is where conventional current flows into the cell. This inward current is carried externally by electrons moving outwards.

In a recharging battery, or an electrolytic cell, the anode is the positive terminal imposed by an external source of potential difference. The current through a recharging battery is opposite to the direction of current during discharge; in other words, the electrode which was the cathode during battery discharge becomes the anode while the battery is recharging.

In battery engineering, it is common to designate one electrode of a rechargeable battery the anode and the other the cathode according to the roles the electrodes play when the battery is discharged. This is despite the fact that the roles are reversed when the battery is charged. When this is done, "anode" simply designates the negative terminal of the battery and "cathode" designates the positive terminal.

In a diode, the anode is the terminal represented by the tail of the arrow symbol (flat side of the triangle), where conventional current flows into the device. Note the electrode naming for diodes is always based on the direction of the forward current (that of the arrow, in which the current flows "most easily"), even for types such as Zener diodes or solar cells where the current of interest is the reverse current.

In vacuum tubes or gas-filled tubes, the anode is the terminal where current enters the tube.

Etymology
The word was coined in 1834 from the Greek ἄνοδος (anodos), 'ascent', by William Whewell, who had been consulted by Michael Faraday over some new names needed to complete a paper on the recently discovered process of electrolysis. In that paper Faraday explained that when an electrolytic cell is oriented so that electric current traverses the "decomposing body" (electrolyte) in a direction "from East to West, or, which will strengthen this help to the memory, that in which the sun appears to move", the anode is where the current enters the electrolyte, on the East side: "ano upwards, odos a way; the way which the sun rises".

The use of 'East' to mean the 'in' direction (actually 'in' → 'East' → 'sunrise' → 'up') may appear contrived. Previously, as related in the first reference cited above, Faraday had used the more straightforward term "eisode" (the doorway where the current enters). His motivation for changing it to something meaning 'the East electrode' (other candidates had been "eastode", "oriode" and "anatolode") was to make it immune to a possible later change in the direction convention for current, whose exact nature was not known at the time. The reference he used to this effect was the Earth's magnetic field direction, which at that time was believed to be invariant. He fundamentally defined his arbitrary orientation for the cell as being that in which the internal current would run parallel to and in the same direction as a hypothetical magnetizing current loop around the local line of latitude which would induce a magnetic dipole field oriented like the Earth's. This made the internal current East to West as previously mentioned, but in the event of a later convention change it would have become West to East, so that the East electrode would not have been the 'way in' any more. Therefore, "eisode" would have become inappropriate, whereas "anode" meaning 'East electrode' would have remained correct with respect to the unchanged direction of the actual phenomenon underlying the current, then unknown but, he thought, unambiguously defined by the magnetic reference. In retrospect the name change was unfortunate, not only because the Greek roots alone do not reveal the anode's function any more, but more importantly because as we now know, the Earth's magnetic field direction on which the "anode" term is based is subject to reversals whereas the current direction convention on which the "eisode" term was based has no reason to change in the future.

Since the later discovery of the electron, an easier to remember and more durably correct technically although historically false, etymology has been suggested: anode, from the Greek anodos, 'way up', 'the way (up) out of the cell (or other device) for electrons'.

Electrolytic anode
In electrochemistry, the anode is where oxidation occurs and is the positive polarity contact in an electrolytic cell. At the anode, anions (negative ions) are forced by the electrical potential to react chemically and give off electrons (oxidation) which then flow up and into the driving circuit. Mnemonics: LEO Red Cat (Loss of Electrons is Oxidation, Reduction occurs at the Cathode), or AnOx Red Cat (Anode Oxidation, Reduction Cathode), or OIL RIG (Oxidation is Loss, Reduction is Gain of electrons), or Roman Catholic and Orthodox (Reduction – Cathode, anode – Oxidation), or LEO the lion says GER (Losing electrons is Oxidation, Gaining electrons is Reduction).

This process is widely used in metals refining. For example, in copper refining, copper anodes, an intermediate product from the furnaces, are electrolysed in an appropriate solution (such as sulfuric acid) to yield high purity (99.99%) cathodes. Copper cathodes produced using this method are also described as electrolytic copper.

Historically, when non-reactive anodes were desired for electrolysis, graphite (called plumbago in Faraday's time) or platinum were chosen. They were found to be some of the least reactive materials for anodes. Platinum erodes very slowly compared to other materials, and graphite crumbles and can produce carbon dioxide in aqueous solutions but otherwise does not participate in the reaction.

Battery or galvanic cell anode

In a battery or galvanic cell, the anode is the negative electrode from which electrons flow out towards the external part of the circuit. Internally the positively charged cations are flowing away from the anode (even though it is negative and therefore would be expected to attract them, this is due to electrode potential relative to the electrolyte solution being different for the anode and cathode metal/electrolyte systems); but, external to the cell in the circuit, electrons are being pushed out through the negative contact and thus through the circuit by the voltage potential as would be expected. Battery manufacturers may regard the negative electrode as the anode, particularly in their technical literature. Though from an electrochemical viewpoint incorrect, it does resolve the problem of which electrode is the anode in a secondary (or rechargeable) cell. Using the traditional definition, the anode switches ends between charge and discharge cycles.

Vacuum tube anode

In electronic vacuum devices such as a cathode-ray tube, the anode is the positively charged electron collector. In a tube, the anode is a charged positive plate that collects the electrons emitted by the cathode through electric attraction. It also accelerates the flow of these electrons.

Diode anode

In a semiconductor diode, the anode is the P-doped layer which initially supplies holes to the junction. In the junction region, the holes supplied by the anode combine with electrons supplied from the N-doped region, creating a depleted zone. As the P-doped layer supplies holes to the depleted region, negative dopant ions are left behind in the P-doped layer ('P' for positive charge-carrier ions). This creates a base negative charge on the anode. When a positive voltage is applied to anode of the diode from the circuit, more holes are able to be transferred to the depleted region, and this causes the diode to become conductive, allowing current to flow through the circuit. The terms anode and cathode should not be applied to a Zener diode, since it allows flow in either direction, depending on the polarity of the applied potential (i.e. voltage).

Sacrificial anode

In cathodic protection, a metal anode that is more reactive to the corrosive environment than the metal system to be protected is electrically linked to the protected system. As a result, the metal anode partially corrodes or dissolves instead of the metal system. As an example, an iron or steel ship's hull may be protected by a zinc sacrificial anode, which will dissolve into the seawater and prevent the hull from being corroded. Sacrificial anodes are particularly needed for systems where a static charge is generated by the action of flowing liquids, such as pipelines and watercraft. Sacrificial anodes are also generally used in tank-type water heaters.

In 1824 to reduce the impact of this destructive electrolytic action on ships hulls, their fastenings and underwater equipment, the scientist-engineer Humphry Davy developed the first and still most widely used marine electrolysis protection system. Davy installed sacrificial anodes made from a more electrically reactive (less noble) metal attached to the vessel hull and electrically connected to form a cathodic protection circuit.

A less obvious example of this type of protection is the process of galvanising iron. This process coats iron structures (such as fencing) with a coating of zinc metal. As long as the zinc remains intact, the iron is protected from the effects of corrosion. Inevitably, the zinc coating becomes breached, either by cracking or physical damage. Once this occurs, corrosive elements act as an electrolyte and the zinc/iron combination as electrodes. The resultant current ensures that the zinc coating is sacrificed but that the base iron does not corrode. Such a coating can protect an iron structure for a few decades, but once the protecting coating is consumed, the iron rapidly corrodes.

If, conversely, tin is used to coat steel, when a breach of the coating occurs it actually accelerates oxidation of the iron.

Impressed current anode
Another cathodic protection is used on the impressed current anode. It is made from titanium and covered with mixed metal oxide. Unlike the sacrificial anode rod, the impressed current anode does not sacrifice its structure. This technology uses an external current provided by a DC source to create the cathodic protection. Impressed current anodes are used in larger structures like pipelines, boats, city water tower, water heaters and more.

Related antonym
The opposite of an anode is a cathode. When the current through the device is reversed, the electrodes switch functions, so the anode becomes the cathode and the cathode becomes anode, as long as the reversed current is applied. The exception is diodes where electrode naming is always based on the forward current direction.

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title: Anode


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Analog television

Analog television is the original television technology that uses analog signals to transmit video and audio. In an analog television broadcast, the brightness, colors and sound are represented by amplitude, phase and frequency of an analog signal.

Analog signals vary over a continuous range of possible values which means that electronic noise and interference may be introduced. Thus with analog, a moderately weak signal becomes snowy and subject to interference. In contrast, picture quality from a digital television (DTV) signal remains good until the signal level drops below a threshold where reception is no longer possible or becomes intermittent.

Analog television may be wireless (terrestrial television and satellite television) or can be distributed over a cable network as cable television.

All broadcast television systems used analog signals before the arrival of DTV. Motivated by the lower bandwidth requirements of compressed digital signals, beginning just after the year 2000, a digital television transition is proceeding in most countries of the world, with different deadlines for the cessation of analog broadcasts. Several countries have made the switch already, with the remaining countries still in progress mostly in Africa, Asia, and South America.

Development
The earliest systems of analog television were mechanical television systems that used spinning disks with patterns of holes punched into the disc to scan an image. A similar disk reconstructed the image at the receiver. Synchronization of the receiver disc rotation was handled through sync pulses broadcast with the image information. Camera systems used similar spinning discs and required intensely bright illumination of the subject for the light detector to work. The reproduced images from these mechanical systems were dim, very low resolution and flickered severely.

Analog television did not begin in earnest as an industry until the development of the cathode-ray tube (CRT), which uses a focused electron beam to trace lines across a phosphor coated surface. The electron beam could be swept across the screen much faster than any mechanical disc system, allowing for more closely spaced scan lines and much higher image resolution. Also, far less maintenance was required of an all-electronic system compared to a mechanical spinning disc system. All-electronic systems became popular with households after World War II.

Standards
Broadcasters of analog television encode their signal using different systems. The official systems of transmission were defined by the ITU in 1961 as: A, B, C, D, E, F, G, H, I, K, K1, L, M and N. These systems determine the number of scan lines, frame rate, channel width, video bandwidth, video-audio separation, and so on. A color encoding scheme (NTSC, PAL, or SECAM) could be added to the base monochrome signal. Using RF modulation the signal is then modulated onto a very high frequency (VHF) or ultra high frequency (UHF) carrier wave. Each frame of a television image is composed of scan lines drawn on the screen. The lines are of varying brightness; the whole set of lines is drawn quickly enough that the human eye perceives it as one image. The process repeats and next sequential frame is displayed, allowing the depiction of motion. The analog television signal contains timing and synchronization information so that the receiver can reconstruct a two-dimensional moving image from a one-dimensional time-varying signal.

The first commercial television systems were black-and-white; the beginning of color television was in the 1950s.

A practical television system needs to take luminance, chrominance (in a color system), synchronization (horizontal and vertical), and audio signals, and broadcast them over a radio transmission. The transmission system must include a means of television channel selection.

Analog broadcast television systems come in a variety of frame rates and resolutions. Further differences exist in the frequency and modulation of the audio carrier. The monochrome combinations still existing in the 1950s were standardized by the International Telecommunication Union (ITU) as capital letters A through N. When color television was introduced, the chrominance information was added to the monochrome signals in a way that black and white televisions ignore. In this way backward compatibility was achieved.

There are three standards for the way the additional color information can be encoded and transmitted. The first was the American NTSC system. The European and Australian PAL and the French and former Soviet Union SECAM standards were developed later and attempt to cure certain defects of the NTSC system. PAL's color encoding is similar to the NTSC systems. SECAM, though, uses a different modulation approach than PAL or NTSC. PAL had a late evolution called PALplus, allowing widescreen broadcasts while remaining fully compatible with existing PAL equipment.

In principle, all three color encoding systems can be used with any scan line/frame rate combination. Therefore, in order to describe a given signal completely, it is necessary to quote the color system plus the broadcast standard as a capital letter. For example, the United States, Canada, Mexico and South Korea use NTSC-M, Japan uses NTSC-J, the UK uses PAL-I, France uses SECAM-L, much of Western Europe and Australia use PAL-B/G, most of Eastern Europe uses SECAM-D/K or PAL-D/K and so on.

Not all of the possible combinations exist. NTSC is only used with system M, even though there were experiments with NTSC-A (405 line) in the UK and NTSC-N (625 line) in part of South America. PAL is used with a variety of 625-line standards (B, G, D, K, I, N) but also with the North American 525-line standard, accordingly named PAL-M. Likewise, SECAM is used with a variety of 625-line standards.

For this reason, many people refer to any 625/25 type signal as PAL and to any 525/30 signal as NTSC, even when referring to digital signals; for example, on DVD-Video, which does not contain any analog color encoding, and thus no PAL or NTSC signals at all.

Although a number of different broadcast television systems are in use worldwide, the same principles of operation apply.

Displaying an image

A cathode-ray tube (CRT) television displays an image by scanning a beam of electrons across the screen in a pattern of horizontal lines known as a raster. At the end of each line, the beam returns to the start of the next line; at the end of the last line, the beam returns to the beginning of the first line at the top of the screen. As it passes each point, the intensity of the beam is varied, varying the luminance of that point. A color television system is similar except there are three beams that scan together and an additional signal known as chrominance controls the color of the spot.

When analog television was developed, no affordable technology for storing video signals existed; the luminance signal had to be generated and transmitted at the same time at which it is displayed on the CRT. It was therefore essential to keep the raster scanning in the camera (or other device for producing the signal) in exact synchronization with the scanning in the television.

The physics of the CRT require that a finite time interval be allowed for the spot to move back to the start of the next line (horizontal retrace) or the start of the screen (vertical retrace). The timing of the luminance signal must allow for this.

The human eye has a characteristic called phi phenomenon. Quickly displaying successive scan images creates the illusion of smooth motion. Flickering of the image can be partially solved using a long persistence phosphor coating on the CRT so that successive images fade slowly. However, slow phosphor has the negative side-effect of causing image smearing and blurring when there is rapid on-screen motion occurring.

The maximum frame rate depends on the bandwidth of the electronics and the transmission system, and the number of horizontal scan lines in the image. A frame rate of 25 or 30 hertz is a satisfactory compromise, while the process of interlacing two video fields of the picture per frame is used to build the image. This process doubles the apparent number of video frames per second and further reduces flicker and other defects in transmission.

Receiving signals
The television system for each country will specify a number of television channels within the UHF or VHF frequency ranges. A channel actually consists of two signals: the picture information is transmitted using amplitude modulation on one carrier frequency, and the sound is transmitted with frequency modulation at a frequency at a fixed offset (typically 4.5 to 6 MHz) from the picture signal.

The channel frequencies chosen represent a compromise between allowing enough bandwidth for video (and hence satisfactory picture resolution), and allowing enough channels to be packed into the available frequency band. In practice a technique called vestigial sideband is used to reduce the channel spacing, which would be nearly twice the video bandwidth if pure AM was used.

Signal reception is invariably done via a superheterodyne receiver: the first stage is a tuner which selects a television channel and frequency-shifts it to a fixed intermediate frequency (IF). The signal amplifier performs amplification to the IF stages from the microvolt range to fractions of a volt.

Extracting the sound
At this point the IF signal consists of a video carrier signal at one frequency and the sound carrier at a fixed offset in frequency. A demodulator recovers the video signal. Also at the output of the same demodulator is a new frequency modulated sound carrier at the offset frequency. In some sets made before 1948, this was filtered out, and the sound IF of about 22 MHz was sent to an FM demodulator to recover the basic sound signal. In newer sets, this new carrier at the offset frequency was allowed to remain as intercarrier sound, and it was sent to an FM demodulator to recover the basic sound signal. One particular advantage of intercarrier sound is that when the front panel fine tuning knob is adjusted, the sound carrier frequency does not change with the tuning, but stays at the above-mentioned offset frequency. Consequently, it is easier to tune the picture without losing the sound.

So the FM sound carrier is then demodulated, amplified, and used to drive a loudspeaker. Until the advent of the NICAM and MTS systems, television sound transmissions were monophonic.

Structure of a video signal
The video carrier is demodulated to give a composite video signal containing luminance, chrominance and synchronization signals. The result is identical to the composite video format used by analog video devices such as VCRs or CCTV cameras. To ensure good linearity and thus fidelity, consistent with affordable manufacturing costs of transmitters and receivers, the video carrier is never modulated to the extent that it is shut off altogether. When intercarrier sound was introduced later in 1948, not completely shutting off the carrier had the side effect of allowing intercarrier sound to be economically implemented.

Each line of the displayed image is transmitted using a signal as shown above. The same basic format (with minor differences mainly related to timing and the encoding of color) is used for PAL, NTSC, and SECAM television systems. A monochrome signal is identical to a color one, with the exception that the elements shown in color in the diagram (the colorburst, and the chrominance signal) are not present.

The front porch is a brief (about 1.5 microsecond) period inserted between the end of each transmitted line of picture and the leading edge of the next line's sync pulse. Its purpose was to allow voltage levels to stabilise in older televisions, preventing interference between picture lines. The front porch is the first component of the horizontal blanking interval which also contains the horizontal sync pulse and the back porch.

The back porch is the portion of each scan line between the end (rising edge) of the horizontal sync pulse and the start of active video. It is used to restore the black level (300 mV) reference in analog video. In signal processing terms, it compensates for the fall time and settling time following the sync pulse.

In color television systems such as PAL and NTSC, this period also includes the colorburst signal. In the SECAM system, it contains the reference subcarrier for each consecutive color difference signal in order to set the zero-color reference.

In some professional systems, particularly satellite links between locations, the digital audio is embedded within the line sync pulses of the video signal, to save the cost of renting a second channel. The name for this proprietary system is Sound-in-Syncs.

Monochrome video signal extraction
The luminance component of a composite video signal varies between 0 V and approximately 0.7 V above the black level. In the NTSC system, there is a blanking signal level used during the front porch and back porch, and a black signal level 75 mV above it; in PAL and SECAM these are identical.

In a monochrome receiver, the luminance signal is amplified to drive the control grid in the electron gun of the CRT. This changes the intensity of the electron beam and therefore the brightness of the spot being scanned. Brightness and contrast controls determine the DC shift and amplification, respectively.

U and V signals
A color signal conveys picture information for each of the red, green, and blue components of an image. However, these are not simply transmitted as three separate signals, because: such a signal would not be compatible with monochrome receivers, an important consideration when color broadcasting was first introduced. It would also occupy three times the bandwidth of existing television, requiring a decrease in the number of television channels available.

Instead, the RGB signals are converted into YUV form, where the Y signal represents the luminance of the colors in the image. Because the rendering of colors in this way is the goal of both monochrome film and television systems, the Y signal is ideal for transmission as the luminance signal. This ensures a monochrome receiver will display a correct picture in black and white, where a given color is reproduced by a shade of gray that correctly reflects how light or dark the original color is.

The U and V signals are color difference signals. The U signal is the difference between the B signal and the Y signal, also known as B minus Y (B-Y), and the V signal is the difference between the R signal and the Y signal, also known as R minus Y (R-Y). The U signal then represents how purplish-blue or its complementary color, yellowish-green, the color is, and the V signal how purplish-red or it's complementary, greenish-cyan, it is. The advantage of this scheme is that the U and V signals are zero when the picture has no color content. Since the human eye is more sensitive to detail in luminance than in color, the U and V signals can be transmitted with reduced bandwidth with acceptable results.

In the receiver, a single demodulator can extract an additive combination of U plus V. An example is the X demodulator used in the X/Z demodulation system. In that same system, a second demodulator, the Z demodulator, also extracts an additive combination of U plus V, but in a different ratio. The X and Z color difference signals are further matrixed into three color difference signals, (R-Y), (B-Y), and (G-Y). The combinations of usually two, but sometimes three demodulators were:

1. (I) / (Q), (as used in the 1954 RCA CTC-2 and the 1985 RCA "Colortrak" series, and the 1954 Arvin, and some professional color monitors in the 1990s),

2. (R-Y) / (Q), as used in the 1955 RCA 21-inch color receiver,

3. (R-Y) / (B-Y), used in the first color receiver on the market (Westinghouse, not RCA),

4. (R-Y) / (G-Y), (as used in the RCA Victor CTC-4 chassis),

5. (R-Y) / (B-Y) / (G-Y),

6. (X) / (Z), as used in many receivers of the late '50s and throughout the '60s.

In the end, further matrixing of the above color-difference signals c through f yielded the three color-difference signals, (R-Y), (B-Y), and (G-Y).

The R, G, and B signals in the receiver needed for the display device (CRT, Plasma display, or LCD display) are electronically derived by matrixing as follows: R is the additive combination of (R-Y) with Y, G is the additive combination of (G-Y) with Y, and B is the additive combination of (B-Y) with Y. All of this is accomplished electronically. It can be seen that in the combining process, the low-resolution portion of the Y signals cancel out, leaving R, G, and B signals able to render a low-resolution image in full color. However, the higher resolution portions of the Y signals do not cancel out, and so are equally present in R, G, and B, producing the higher-resolution image detail in monochrome, although it appears to the human eye as a full-color and full-resolution picture.

NTSC and PAL systems
In the NTSC and PAL color systems, U and V are transmitted by using quadrature amplitude modulation of a subcarrier. This kind of modulation applies two independent signals to one subcarrier, with the idea that both signals will be recovered independently at the receiving end. For NTSC, the subcarrier is at 3.58 MHz. For the PAL system it is at 4.43 MHz. The subcarrier itself is not included in the modulated signal (suppressed carrier), it is the subcarrier sidebands that carry the U and V information. The usual reason for using suppressed carrier is that it saves on transmitter power. In this application a more important advantage is that the color signal disappears entirely in black and white scenes. The subcarrier is within the bandwidth of the main luminance signal and consequently can cause undesirable artifacts on the picture, all the more noticeable in black and white receivers.

A small sample of the subcarrier, the colorburst, is included in the horizontal blanking portion, which is not visible on the screen. This is necessary to give the receiver a phase reference for the modulated signal. Under quadrature amplitude modulation the modulated chrominance signal changes phase as compared to its subcarrier and also changes amplitude. The chrominance amplitude (when considered together with the Y signal) represents the approximate saturation of a color, and the chrominance phase against the subcarrier reference approximately represents the hue of the color. For particular test colors found in the test color bar pattern, exact amplitudes and phases are sometimes defined for test and troubleshooting purposes only.

Due to the nature of the quadrature amplitude modulation process that created the chrominance signal, at certain times, the signal represents only the U signal, and 70 nanoseconds (NTSC) later, it represents only the V signal. About 70 nanoseconds later still, -U, and another 70 nanoseconds, -V. So to extract U, a synchronous demodulator is utilized, which uses the subcarrier to briefly gate the chroma every 280 nanoseconds, so that the output is only a train of discrete pulses, each having an amplitude that is the same as the original U signal at the corresponding time. In effect, these pulses are discrete-time analog samples of the U signal. The pulses are then low-pass filtered so that the original analog continuous-time U signal is recovered. For V, a 90-degree shifted subcarrier briefly gates the chroma signal every 280 nanoseconds, and the rest of the process is identical to that used for the U signal.

Gating at any other time than those times mentioned above will yield an additive mixture of any two of U, V, -U, or -V. One of these off-axis (that is, of the U and V axis) gating methods is called I/Q demodulation. Another much more popular off-axis scheme was the X/Z demodulation system. Further matrixing recovered the original U and V signals. This scheme was actually the most popular demodulator scheme throughout the 1960s.

The above process uses the subcarrier. But as previously mentioned, it was deleted before transmission, and only the chroma is transmitted. Therefore, the receiver must reconstitute the subcarrier. For this purpose, a short burst of the subcarrier, known as the colorburst, is transmitted during the back porch (re-trace blanking period) of each scan line. A subcarrier oscillator in the receiver locks onto this signal (see phase-locked loop) to achieve a phase reference, resulting in the oscillator producing the reconstituted subcarrier.

NTSC uses this process unmodified. Unfortunately, this often results in poor color reproduction due to phase errors in the received signal, caused sometimes by multipath, but mostly by poor implementation at the studio end. With the advent of solid-state receivers, cable TV, and digital studio equipment for conversion to an over-the-air analog signal, these NTSC problems have been largely fixed, leaving operator error at the studio end as the sole color rendition weakness of the NTSC system. In any case, the PAL D (delay) system mostly corrects these kinds of errors by reversing the phase of the signal on each successive line, and averaging the results over pairs of lines. This process is achieved by the use of a 1H (where H = horizontal scan frequency) duration delay line. Phase shift errors between successive lines are therefore canceled out and the wanted signal amplitude is increased when the two in-phase (coincident) signals are re-combined.

NTSC is more spectrum efficient than PAL, giving more picture detail for a given bandwidth. This is because sophisticated comb filters in receivers are more effective with NTSC's 4 color frame sequence compared to PAL's 8-field sequence. However, in the end, the larger channel width of most PAL systems in Europe still gives PAL systems the edge in transmitting more picture detail.

SECAM system
In the SECAM television system, U and V are transmitted on alternate lines, using simple frequency modulation of two different color subcarriers.

In some analog color CRT displays, starting in 1956, the brightness control signal (luminance) is fed to the cathode connections of the electron guns, and the color difference signals (chrominance signals) are fed to the control grids connections. This simple CRT matrix mixing technique was replaced in later solid state designs of signal processing with the original matrixing method used in the 1954 and 1955 color TV receivers.

Synchronization
Synchronizing pulses added to the video signal at the end of every scan line and video frame ensure that the sweep oscillators in the receiver remain locked in step with the transmitted signal so that the image can be reconstructed on the receiver screen.

A sync separator circuit detects the sync voltage levels and sorts the pulses into horizontal and vertical sync.

Horizontal synchronization
The horizontal sync pulse separates the scan lines. The horizontal sync signal is a single short pulse that indicates the start of every line. The rest of the scan line follows, with the signal ranging from 0.3 V (black) to 1 V (white), until the next horizontal or vertical synchronization pulse.

The format of the horizontal sync pulse varies. In the 525-line NTSC system it is a 4.85 μs pulse at 0 V. In the 625-line PAL system the pulse is 4.7 μs at 0 V. This is lower than the amplitude of any video signal (blacker than black) so it can be detected by the level-sensitive sync separator circuit of the receiver.

Two-timing intervals are defined – the front porch between the end of the displayed video and the start of the sync pulse, and the back porch after the sync pulse and before the displayed video. These and the sync pulse itself are called the horizontal blanking (or retrace) interval and represent the time that the electron beam in the CRT is returning to the start of the next display line.

Vertical synchronization
Vertical synchronization separates the video fields. In PAL and NTSC, the vertical sync pulse occurs within the vertical blanking interval. The vertical sync pulses are made by prolonging the length of horizontal sync pulses through almost the entire length of the scan line.

The vertical sync signal is a series of much longer pulses, indicating the start of a new field. The sync pulses occupy the whole line interval of a number of lines at the beginning and end of a scan; no picture information is transmitted during vertical retrace. The pulse sequence is designed to allow horizontal sync to continue during vertical retrace; it also indicates whether each field represents even or odd lines in interlaced systems (depending on whether it begins at the start of a horizontal line, or midway through).

The format of such a signal in 525-line NTSC is:
 * pre-equalizing pulses (6 to start scanning odd lines, 5 to start scanning even lines)
 * long-sync pulses (5 pulses)
 * post-equalizing pulses (5 to start scanning odd lines, 4 to start scanning even lines)

Each pre- or post-equalizing pulse consists of half a scan line of black signal: 2 μs at 0 V, followed by 30 μs at 0.3 V. Each long sync pulse consists of an equalizing pulse with timings inverted: 30 μs at 0 V, followed by 2 μs at 0.3 V.

In video production and computer graphics, changes to the image are often performed during the vertical blanking interval to avoid visible discontinuity of the image. If this image in the framebuffer is updated with a new image while the display is being refreshed, the display shows a mishmash of both frames, producing page tearing partway down the image.

Horizontal and vertical hold
The sweep (or deflection) oscillators were designed to run without a signal from the television station (or VCR, computer, or other composite video source). This allows the television receiver to display a raster and to allow an image to be presented during antenna placement. With sufficient signal strength, the receiver's sync separator circuit would split timebase pulses from the incoming video and use them to reset the horizontal and vertical oscillators at the appropriate time to synchronize with the signal from the station.

The free-running oscillation of the horizontal circuit is especially critical, as the horizontal deflection circuits typically power the flyback transformer (which provides acceleration potential for the CRT) as well as the filaments for the high voltage rectifier tube and sometimes the filament(s) of the CRT itself. Without the operation of the horizontal oscillator and output stages in these television receivers, there would be no illumination of the CRT's face.

The lack of precision timing components in early equipment meant that the timebase circuits occasionally needed manual adjustment. If their free-run frequencies were too far from the actual line and field rates, the circuits would not be able to follow the incoming sync signals. Loss of horizontal synchronization usually resulted in an unwatchable picture; loss of vertical synchronization would produce an image rolling up or down the screen.

Older analog television receivers often provide manual controls to adjust horizontal and vertical timing. The adjustment takes the form of horizontal hold and vertical hold controls, usually on the front panel along with other common controls. These adjust the free-run frequencies of the corresponding timebase oscillators.

A slowly rolling vertical picture demonstrates that the vertical oscillator is nearly synchronized with the television station but is not locking to it, often due to a weak signal or a failure in the sync separator stage not resetting the oscillator.

Horizontal sync errors cause the image to be torn diagonally and repeated across the screen as if it were wrapped around a screw or a barber's pole; the greater the error, the more copies of the image will be seen at once wrapped around the barber pole.

By the early 1980s the efficacy of the synchronization circuits, plus the inherent stability of the sets' oscillators, had been improved to the point where these controls were no longer necessary. Integrated Circuits which eliminated the horizontal hold control were starting to appear as early as 1969.

The final generations of analog television receivers used IC-based designs where the receiver's timebases were derived from accurate crystal oscillators. With these sets, adjustment of the free-running frequency of either sweep oscillator was unnecessary and unavailable.

Horizontal and vertical hold controls were rarely used in CRT-based computer monitors, as the quality and consistency of components were quite high by the advent of the computer age, but might be found on some composite monitors used with the 1970s–80s home or personal computers.

Components of a television system

The tuner is the object which, with the aid of an antenna, isolates the television signals received over the air. There are two types of tuners in analog television, VHF and UHF tuners. The VHF tuner selects the VHF television frequency. This consists of a 4 MHz video bandwidth and about 100 kHz audio bandwidth. It then amplifies the signal and converts it to a 45.75 MHz Intermediate Frequency (IF) amplitude-modulated video and a 41.25 MHz IF frequency-modulated audio carrier.

The IF amplifiers are centered at 44 MHz for optimal frequency transference of the audio and video carriers. Like radio, television has automatic gain control (AGC). This controls the gain of the IF amplifier stages and the tuner.

The video amp and output amplifier is implemented using a pentode or a power transistor. The filter and demodulator separates the 45.75 MHz video from the 41.25 MHz audio then it simply uses a diode to detect the video signal. After the video detector, the video is amplified and sent to the sync separator and then to the picture tube.

The audio signal goes to a 4.5 MHz amplifier. This amplifier prepares the signal for the 4.5 Mhz detector. It then goes through a 4.5 MHz IF transformer to the detector. In television, there are 2 ways of detecting FM signals. One way is by the ratio detector. This is simple but very hard to align. The next is a relatively simple detector. This is the quadrature detector. It was invented in 1954. The first tube designed for this purpose was the 6BN6 type. It is easy to align and simple in circuitry. It was such a good design that it is still being used today in the Integrated circuit form. After the detector, it goes to the audio amplifier.

Image synchronization is achieved by transmitting negative-going pulses. The horizontal sync signal is a single short pulse that indicates the start of every line. Two-timing intervals are defined – the front porch between the end of the displayed video and the start of the sync pulse, and the back porch after the sync pulse and before the displayed video. These and the sync pulse itself are called the horizontal blanking (or retrace) interval and represent the time that the electron beam in the CRT is returning to the start of the next display line.

The vertical sync signal is a series of much longer pulses, indicating the start of a new field. The vertical sync pulses occupy the whole of line interval of a number of lines at the beginning and end of a scan; no picture information is transmitted during vertical retrace. The pulse sequence is designed to allow horizontal sync to continue during vertical retrace.

A sync separator circuit detects the sync voltage levels and extracts and conditions signals that the horizontal and vertical oscillators can use to keep in sync with the video. It also forms the AGC voltage.

The horizontal and vertical oscillators form the raster on the CRT. They are driven by the sync separator. There are many ways to create these oscillators. The earliest is the thyratron oscillator. Although it is known to drift, it makes a perfect sawtooth wave. This sawtooth wave is so good that no linearity control is needed. This oscillator was designed for the electrostatic deflection CRTs but also found some use in electromagnetically deflected CRTs. The next oscillator developed was the blocking oscillator which uses a transformer to create a sawtooth wave. This was only used for a brief time period and never was very popular. Finally the multivibrator was probably the most successful. It needed more adjustment than the other oscillators, but it is very simple and effective. This oscillator was so popular that it was used from the early 1950s until today.

Two oscillator amplifiers are needed. The vertical amplifier directly drives the yoke. Since it operates at 50 or 60 Hz and drives an electromagnet, it is similar to an audio amplifier. Because of the rapid deflection required, the horizontal oscillator requires a high-power flyback transformer driven by a high-powered tube or transistor. Additional windings on this flyback transformer typically power other parts of the system.

Loss of horizontal synchronization usually results in a scrambled and unwatchable picture; loss of vertical synchronization produces an image rolling up or down the screen.

Timebase circuits
In an analog receiver with a CRT display sync pulses are fed to horizontal and vertical timebase circuits (commonly called sweep circuits in the United States), each consisting of an oscillator and an amplifier. These generate modified sawtooth and parabola current waveforms to scan the electron beam. Engineered waveform shapes are necessary to make up for the distance variations from the electron beam source and the screen surface. The oscillators are designed to free-run at frequencies very close to the field and line rates, but the sync pulses cause them to reset at the beginning of each scan line or field, resulting in the necessary synchronization of the beam sweep with the originating signal. The output waveforms from the timebase amplifiers are fed to the horizontal and vertical deflection coils wrapped around the CRT tube. These coils produce magnetic fields proportional to the changing current, and these deflect the electron beam across the screen.

In the 1950s, the power for these circuits was derived directly from the mains supply. A simple circuit consisted of a series voltage dropper resistance and a rectifier. This avoided the cost of a large high-voltage mains supply (50 or 60 Hz) transformer. It was inefficient and produced a lot of heat.

In the 1960s, semiconductor technology was introduced into timebase circuits. During the late 1960s in the UK, synchronous (with the scan line rate) power generation was introduced into solid state receiver designs.

In the UK use of the simple (50 Hz) types of power, circuits were discontinued as thyristor based switching circuits were introduced. The reason for design changes arose from the electricity supply contamination problems arising from EMI, and supply loading issues due to energy being taken from only the positive half cycle of the mains supply waveform.

CRT flyback power supply
Most of the receiver's circuitry (at least in transistor- or IC-based designs) operates from a comparatively low-voltage DC power supply. However, the anode connection for a cathode-ray tube requires a very high voltage (typically 10–30 kV) for correct operation.

This voltage is not directly produced by the main power supply circuitry; instead, the receiver makes use of the circuitry used for horizontal scanning. Direct current (DC), is switched through the line output transformer, and alternating current (AC) is induced into the scan coils. At the end of each horizontal scan line the magnetic field, which has built up in both transformer and scan coils by the current, is a source of latent electromagnetic energy. This stored collapsing magnetic field energy can be captured. The reverse flow, short duration, (about 10% of the line scan time) current from both the line output transformer and the horizontal scan coil is discharged again into the primary winding of the flyback transformer by the use of a rectifier which blocks this counter-electromotive force. A small value capacitor is connected across the scan-switching device. This tunes the circuit inductances to resonate at a much higher frequency. This lengthens the flyback time from the extremely rapid decay rate that would result if they were electrically isolated during this short period. One of the secondary windings on the flyback transformer then feeds this brief high-voltage pulse to a Cockcroft–Walton generator design voltage multiplier. This produces the required high-voltage supply. A flyback converter is a power supply circuit operating on similar principles.

A typical modern design incorporates the flyback transformer and rectifier circuitry into a single unit with a captive output lead, known as a diode split line output transformer or an Integrated High Voltage Transformer (IHVT), so that all high-voltage parts are enclosed. Earlier designs used a separate line output transformer and a well-insulated high-voltage multiplier unit. The high frequency (15 kHz or so) of the horizontal scanning allows reasonably small components to be used.

Transition to digital
In many countries, over-the-air broadcast television of analog audio and analog video signals has been discontinued to allow the re-use of the television broadcast radio spectrum for other services.

The first country to make a wholesale switch to digital over-the-air (terrestrial television) broadcasting was Luxembourg in 2006, followed later in 2006 by the Netherlands. The Digital television transition in the United States for high-powered transmission was completed on 12 June 2009, the date that the Federal Communications Commission (FCC) set. Almost two million households could no longer watch television because they had not prepared for the transition. The switchover had been delayed by the DTV Delay Act. While the majority of the viewers of over-the-air broadcast television in the U.S. watch full-power stations (which number about 1800), there are three other categories of television stations in the U.S.: low-power broadcasting stations, class A stations, and television translator stations. These were given later deadlines.

In Japan, the switch to digital began in northeastern Ishikawa Prefecture on 24 July 2010 and ended in 43 of the country's 47 prefectures (including the rest of Ishikawa) on 24 July 2011, but in Fukushima, Iwate, and Miyagi prefectures, the conversion was delayed to 31 March 2012, due to complications from the 2011 Tōhoku earthquake and tsunami and its related nuclear accidents.

In Canada, most of the larger cities turned off analog broadcasts on 31 August 2011.

China had scheduled to end analog broadcasting between 2015 and 2021.

Brazil switched to digital television on 2 December 2007 Only in São Paulo. In 2017 it was estimated that Brazil would end analog broadcasting in 2023.

In Malaysia, the Malaysian Communications & Multimedia Commission (MCMC) advertised for tender bids to be submitted in the third quarter of 2009 for the 470 through 742 MHz UHF allocation, to enable Malaysia's broadcast system to move into DTV. The new broadcast band allocation would result in Malaysia's having to build an infrastructure for all broadcasters, using a single digital terrestrial transmission/television broadcast (DTTB) channel. Large portions of Malaysia are covered by television broadcasts from Singapore, Thailand, Brunei, and Indonesia (from Borneo and Batam). Starting from 1 November 2019, all regions in Malaysia were no longer using the analog system after the states of Sabah and Sarawak finally turned it off on 31 October 2019.

In Singapore, digital television under DVB-T2 began on 16 December 2013. The switchover was delayed many times until analog TV was switched off at midnight on 2 January 2019.

In the Philippines, the National Telecommunications Commission required all broadcasting companies to end analog broadcasting on 31 December 2015 at 11:59 p.m. Due to delay of the release of the implementing rules and regulations for digital television broadcast, the target date was moved to 2020. Full digital broadcast is expected in 2021 and all of the analog TV services should be shut down by the end of 2023. However, in February 2023, the NTC postponed the ASO/DTV transition to 2025 due to many provincial television stations not being ready to start their digital TV transmissions.

In the Russian Federation, the Russian Television and Radio Broadcasting Network (RTRS) disabled analog broadcasting of federal channels in five stages, shutting down broadcasting in multiple federal subjects at each stage. The first region to have analog broadcasting disabled was Tver Oblast on 3 December 2018, and the switchover was completed on 14 October 2019. During the transition, DVB-T2 receivers and monetary compensations for purchasing of terrestrial or satellite digital TV reception equipment were provided to disabled people, World War II veterans, certain categories of retirees and households with income per member below living wage.

title: Analog television


text:
April 11

Pre-1600

 * 491 – Flavius Anastasius becomes Byzantine emperor, with the name of Anastasius I.
 * 1241 – Batu Khan defeats Béla IV of Hungary at the Battle of Mohi.
 * 1512 – War of the League of Cambrai: Franco-Ferrarese forces led by Gaston de Foix and Alfonso I d'Este win the Battle of Ravenna against the Papal-Spanish forces.
 * 1544 – Italian War of 1542–46: A French army defeats Habsburg forces at the Battle of Ceresole, but fails to exploit its victory.

1601–1900

 * 1689 – William III and Mary II are crowned as joint sovereigns of Great Britain on the same day that the Scottish Parliament concurs with the English decision of 12 February.
 * 1713 – France and Great Britain sign the Treaty of Utrecht, bringing an end to the War of the Spanish Succession (Queen Anne's War). Britain accepts Philip V as King of Spain, while Philip renounces any claim to the French throne.
 * 1727 – Premiere of Johann Sebastian Bach's St Matthew Passion BWV 244b at St. Thomas Church in Leipzig, Electorate of Saxony (now Germany).
 * 1809 – Battle of the Basque Roads: Admiral Lord Gambier fails to support Captain Lord Cochrane, leading to an incomplete British victory over the French fleet.
 * 1814 – The Treaty of Fontainebleau ends the War of the Sixth Coalition against Napoleon Bonaparte, and forces him to abdicate unconditionally for the first time.
 * 1856 – Second Battle of Rivas: Juan Santamaría burns down the hostel where William Walker's filibusters are holed up.
 * 1868 – Former shōgun Tokugawa Yoshinobu surrenders Edo Castle to Imperial forces, marking the end of the Tokugawa shogunate.
 * 1876 – The Benevolent and Protective Order of Elks is organized.
 * 1881 – Spelman College is founded in Atlanta, Georgia as the Atlanta Baptist Female Seminary, an institute of higher education for African-American women.

1901–present

 * 1908 – SMS Blücher, the last armored cruiser to be built by the Imperial German Navy, is launched.
 * 1909 – The city of Tel Aviv is founded.
 * 1921 – Emir Abdullah establishes the first centralised government in the newly created British protectorate of Transjordan.
 * 1935 – Stresa Front: opening of the conference between the British Prime Minister Ramsay MacDonald, the Italian Prime Minister Benito Mussolini and the French Minister for Foreign Affairs Pierre Laval to condemn the German violations of the Treaty of Versailles.
 * 1945 – World War II: American forces liberate the Buchenwald concentration camp.
 * 1951 – Korean War: President Truman relieves Douglas MacArthur of the command of American forces in Korea and Japan.
 * 1951  – The Stone of Scone, the stone upon which Scottish monarchs were traditionally crowned, is found on the site of the altar of Arbroath Abbey. It had been taken by Scottish nationalist students from its place in Westminster Abbey.
 * 1952 – Bolivian National Revolution: Rebels take over Palacio Quemado.
 * 1952  – Pan Am Flight 526A ditches near San Juan-Isla Grande Airport in San Juan, Puerto Rico, after experiencing an engine failure, killing 52 people.
 * 1955 – The Air India Kashmir Princess is bombed and crashes in a failed assassination attempt on Zhou Enlai by the Kuomintang.
 * 1957 – United Kingdom agrees to Singaporean self-rule.
 * 1961 – The trial of Adolf Eichmann begins in Jerusalem.
 * 1963 – Pope John XXIII issues Pacem in terris, the first encyclical addressed to all Christians instead of only Catholics, and which described the conditions for world peace in human terms.
 * 1964 – Brazilian Marshal Humberto de Alencar Castelo Branco is elected president by the National Congress.
 * 1965 – The Palm Sunday tornado outbreak of 1965: Fifty-five tornadoes hit in six Midwestern states of the United States, killing 266 people.
 * 1968 – US President Lyndon B. Johnson signs the Civil Rights Act of 1968, prohibiting discrimination in the sale, rental, and financing of housing.
 * 1968  – A failed assassination attempt on Rudi Dutschke, leader of the German student movement, leaves Dutschke suffering from brain damage.
 * 1970 – Apollo Program: Apollo 13 is launched.
 * 1976 – The Apple I is created.
 * 1977 – London Transport's Silver Jubilee AEC Routemaster buses are launched.
 * 1979 – Ugandan dictator Idi Amin is deposed.
 * 1981 – A massive riot in Brixton, south London results in almost 300 police injuries and 65 serious civilian injuries.
 * 1986 – FBI Miami Shootout: A gun battle in broad daylight in Dade County, Florida between two bank/armored car robbers and pursuing FBI agents. During the firefight, FBI agents Jerry L. Dove and Benjamin P. Grogan were killed, while five other agents were wounded. As a result, the popular .40 S&W cartridge was developed.
 * 1987 – The London Agreement is secretly signed between Israeli Foreign Affairs Minister Shimon Peres and King Hussein of Jordan.
 * 1990 – Customs officers in Middlesbrough, England, seize what they believe to be the barrel of a massive gun on a ship bound for Iraq.
 * 1993 – Four hundred fifty prisoners rioted at the Southern Ohio Correctional Facility in Lucasville, Ohio, and continued to do so for ten days, citing grievances related to prison conditions, as well as the forced vaccination of Nation of Islam prisoners (for tuberculosis) against their religious beliefs.
 * 2001 – The detained crew of a United States EP-3E aircraft that landed in Hainan, China after a collision with a J-8 fighter, is released.
 * 2002 – The Ghriba synagogue bombing by al-Qaeda kills 21 in Tunisia.
 * 2002  – Over two hundred thousand people march in Caracas towards the presidential palace to demand the resignation of President Hugo Chávez. Nineteen protesters are killed.
 * 2006 – Iranian president Mahmoud Ahmadinejad announces Iran's claim to have successfully enriched uranium.
 * 2007 – Algiers bombings: Two bombings in Algiers kill 33 people and wound a further 222 others.
 * 2008 – Kata Air Transport Flight 007 crashes while attempting an emergency landing at Chișinău International Airport, killing eight.
 * 2011 – An explosion in the Minsk Metro, Belarus kills 15 people and injures 204 others.
 * 2012 – A pair of great earthquakes occur in the Wharton Basin west of Sumatra in Indonesia. The maximum Mercalli intensity of this strike-slip doublet earthquake is VII (Very strong). Ten are killed, twelve are injured, and a non-destructive tsunami is observed on the island of Nias.
 * 2018 – An Ilyushin Il-76 which was owned and operated by the Algerian Air Force crashes near Boufarik, Algeria, killing 257.
 * 2021 – Twenty year old Daunte Wright is shot and killed in Brooklyn Center, Minnesota by officer Kimberly Potter, sparking protests in the city, when the officer allegedly mistakes her own gun for her taser.
 * 2023 – During the Pazigyi massacre, an airstrike conducted by the Myanmar Air Force kills at least 100 villagers in Pazigyi, Sagaing Region.

Pre-1600

 * 145 – Septimius Severus, Roman emperor (probable; d. 211)
 * 1184 – William of Winchester, Lord of Lüneburg (d. 1213)
 * 1348 – Andronikos IV Palaiologos, Byzantine Emperor (d. 1385)
 * 1357 – John I of Portugal (d. 1433)
 * 1370 – Frederick I, Elector of Saxony (d. 1428)
 * 1374 – Roger Mortimer, 4th Earl of March, heir to the throne of England (d. 1398)
 * 1493 – George I, Duke of Pomerania (d. 1531)
 * 1591 – Bartholomeus Strobel, Silezian painter (d. 1650)
 * 1592 – John Eliot, English lawyer and politician (d. 1632)

1601–1900

 * 1644 – Marie Jeanne Baptiste of Savoy-Nemours, Duchess of Savoy (d. 1724)
 * 1658 – James Hamilton, 4th Duke of Hamilton, Scottish peer (d. 1712)
 * 1683 – Jean-Joseph Mouret, French composer and conductor (d. 1738)
 * 1715 – John Alcock, English organist and composer (d. 1806)
 * 1721 – David Zeisberger, Czech-American clergyman and missionary (d. 1808)
 * 1722 – Christopher Smart, English actor, playwright, and poet (d. 1771)
 * 1749 – Adélaïde Labille-Guiard, French miniaturist and portrait painter (d. 1803)
 * 1755 – James Parkinson, English surgeon, geologist, and paleontologist (d. 1824)
 * 1770 – George Canning, Irish-English lawyer and politician, Prime Minister of the United Kingdom (d. 1827)
 * 1794 – Edward Everett, English-American educator and politician, 15th Governor of Massachusetts (d. 1865)
 * 1798 – Macedonio Melloni, Italian physicist and academic (d. 1854)
 * 1819 – Charles Hallé, German-English pianist and conductor (d. 1895)
 * 1825 – Ferdinand Lassalle, German philosopher and jurist (d. 1864)
 * 1827 – Jyotirao Phule, Indian scholar, philosopher, and activist (d. 1890)
 * 1830 – John Douglas, English architect (d. 1911)
 * 1854 – Hugh Massie, Australian cricketer (d. 1938)
 * 1856 – Arthur Shrewsbury, English cricketer and rugby player (d. 1903)
 * 1859 – Stefanos Thomopoulos, Greek historian and author (d. 1939)
 * 1862 – William Wallace Campbell, American astronomer and academic (d. 1938)
 * 1862  – Charles Evans Hughes, American lawyer and politician, 44th United States Secretary of State (d. 1948)
 * 1864 – Johanna Elberskirchen, German author and activist (d. 1943)
 * 1866 – Bernard O'Dowd, Australian journalist, author, and poet (d. 1953)
 * 1867 – Mark Keppel, American educator (d. 1928)
 * 1869 – Gustav Vigeland, Norwegian sculptor, designed the Nobel Peace Prize medal (d. 1943)
 * 1871 – Gyula Kellner, Hungarian runner (d. 1940)
 * 1872 – Aleksandër Stavre Drenova, Albanian poet, rilindas and author of national anthem of Albania (d. 1947)
 * 1873 – Edward Lawson, English soldier, Victoria Cross recipient (d. 1955)
 * 1876 – Paul Henry, Irish painter (d. 1958)
 * 1876  – Ivane Javakhishvili, Georgian historian and academic (d. 1940)
 * 1878 – Percy Lane Oliver, British pioneer of volunteer blood donation (d. 1944)
 * 1879 – Bernhard Schmidt, Estonian-German astronomer and optician (d. 1935)
 * 1887 – Jamini Roy, Indian painter (d. 1972)
 * 1893 – Dean Acheson, American lawyer and politician, 51st United States Secretary of State (d. 1971)
 * 1896 – Léo-Paul Desrosiers, Canadian journalist and author (d. 1967)
 * 1899 – Percy Lavon Julian, African-American chemist and academic (d. 1975)
 * 1900 – Sándor Márai, Hungarian journalist and author (d. 1989)

1901–present

 * 1903 – Misuzu Kaneko, Japanese poet (d. 1930)
 * 1904 – K. L. Saigal, Indian singer and actor (d. 1947)
 * 1905 – Attila József, Hungarian poet and educator (d. 1937)
 * 1906 – Dale Messick, American author and illustrator (d. 2005)
 * 1907 – Paul Douglas, American actor (d. 1959)
 * 1908 – Jane Bolin, American lawyer and judge (d. 2007)
 * 1908  – Masaru Ibuka, Japanese businessman, co-founded Sony (d. 1997)
 * 1908  – Dan Maskell, English tennis player and sportscaster (d. 1992)
 * 1908  – Leo Rosten, Polish-American author and academic (d. 1997)
 * 1910 – António de Spínola, Portuguese general and politician, 14th President of Portugal (d. 1996)
 * 1912 – John Levy, American bassist and businessman (d. 2012)
 * 1913 – Oleg Cassini, French-American fashion designer (d. 2006)
 * 1914 – Norman McLaren, Scottish-Canadian animator, director, and producer (d. 1987)
 * 1914  – Robert Stanfield, Canadian economist, lawyer, and politician, 17th Premier of Nova Scotia (d. 2003)
 * 1914  – Dorothy Lewis Bernstein, American mathematician (d. 1988)
 * 1916 – Alberto Ginastera, Argentinian pianist and composer (d. 1983)
 * 1916  – Howard W. Koch, American director and producer (d. 2001)
 * 1917 – David Westheimer, American soldier, journalist, and author (d. 2005)
 * 1918 – Richard Wainwright, English soldier and politician (d. 2003)
 * 1919 – Raymond Carr, English historian and academic (d. 2015)
 * 1920 – Emilio Colombo, Italian lawyer and politician, 40th Prime Minister of Italy (d. 2013)
 * 1920  – William Royer, American soldier and politician (d. 2013)
 * 1921 – Jim Hearn, American baseball player (d. 1998)
 * 1921  – Jack Rayner, Australian rugby league player and coach (d. 2008)
 * 1922 – Arved Viirlaid, Estonian-Canadian soldier and author (d. 2015)
 * 1923 – George J. Maloof, Sr., American businessman (d. 1980)
 * 1924 – Mohammad Naseem, Pakistani-English activist and politician (d. 2014)
 * 1925 – Yuriy Lituyev, Russian hurdler and commander (d. 2000)
 * 1925  – Viola Liuzzo, American civil rights activist (d. 1965)
 * 1925  – Viktor Masing, Estonian botanist and ecologist (d. 2001)
 * 1925  – Pierre Péladeau, Canadian businessman, founded Quebecor (d. 1997)
 * 1926 – David Manker Abshire, American commander and diplomat, United States Permanent Representative to NATO (d. 2014)
 * 1926  – Victor Bouchard, Canadian pianist and composer (d. 2011)
 * 1926  – Karl Rebane, Estonian physicist and academic (d. 2007)
 * 1927 – Lokesh Chandra, Indian historian
 * 1928 – Ethel Kennedy, American philanthropist
 * 1928  – Edwin Pope, American journalist and author (d. 2017)
 * 1928  – Tommy Tycho, Hungarian-Australian pianist, composer, and conductor (d. 2013)
 * 1930 – Nicholas F. Brady, American businessman and politician, 68th United States Secretary of the Treasury
 * 1930  – Walter Krüger, German javelin thrower (d. 2018)
 * 1930  – Anton LaVey, American occultist, founded the Church of Satan (d. 1997)
 * 1931 – Lewis Jones, Welsh rugby player and coach (d. 2024)
 * 1932 – Joel Grey, American actor, singer, and dancer
 * 1933 – Tony Brown, American journalist and academic
 * 1934 – Mark Strand, Canadian-born American poet, essayist, and translator (d. 2014)
 * 1934  – Ron Pember, English actor, director and playwright (d. 2022)
 * 1935 – Richard Berry, American singer-songwriter (d. 1997)
 * 1936 – Brian Noble, English bishop (d. 2019)
 * 1937 – Jill Gascoine, English actress and author (d. 2020)
 * 1938 – Gerry Baker, American soccer player and manager (d. 2013)
 * 1938  – Michael Deaver, American politician, Deputy White House Chief of Staff (d. 2007)
 * 1938  – Reatha King, American chemist and businesswoman
 * 1939 – Luther Johnson, American singer and guitarist (d. 2022)
 * 1939  – Louise Lasser, American actress
 * 1940 – Col Firmin, Australian politician (d. 2013)
 * 1940  – Władysław Komar, Polish shot putter and actor (d. 1998)
 * 1941 – Ellen Goodman, American journalist and author
 * 1941  – Shirley Stelfox, English actress (d. 2015)
 * 1942 – Anatoly Berezovoy, Russian colonel, pilot, and astronaut (d. 2014)
 * 1942  – Hattie Gossett, American writer
 * 1942  – James Underwood, English pathologist and academic
 * 1943 – John Montagu, 11th Earl of Sandwich, English businessman and politician
 * 1943  – Harley Race, American wrestler and trainer (d. 2019)
 * 1944 – Peter Barfuß, German footballer
 * 1944  – John Milius, American director, producer, and screenwriter
 * 1945 – John Krebs, Baron Krebs, English zoologist and academic
 * 1946 – Chris Burden, American sculptor, illustrator, and academic (d. 2015)
 * 1946  – Bob Harris, English journalist and radio host
 * 1947 – Lev Bulat, Ukrainian-Russian physicist and academic (d. 2016)
 * 1947  – Uli Edel, German director and screenwriter
 * 1947  – Frank Mantooth, American pianist and composer (d. 2004)
 * 1947  – Peter Riegert, American actor, screenwriter and film director
 * 1947  – Michael T. Wright, English engineer and academic (d. 2015)
 * 1949 – Bernd Eichinger, German director and producer (d. 2011)
 * 1950 – Bill Irwin, American actor and clown
 * 1951 – Paul Fox, English singer and guitarist (d. 2007)
 * 1952 – Nancy Honeytree, American singer and guitarist
 * 1952  – Indira Samarasekera, Sri Lankan engineer and academic
 * 1952  – Peter Windsor, English-Australian journalist and sportscaster
 * 1953 – Guy Verhofstadt, Belgian politician, 47th Prime Minister of Belgium
 * 1953  – Andrew Wiles, English mathematician and academic
 * 1954 – Abdullah Atalar, Turkish engineer and academic
 * 1954  – Aleksandr Averin, Azerbaijani cyclist and coach
 * 1954  – Francis Lickerish, English guitarist and composer
 * 1954  – David Perrett, Scottish psychologist and academic
 * 1954  – Ian Redmond, English biologist and conservationist
 * 1954  – Willie Royster, American baseball player (d. 2015)
 * 1955 – Kevin Brady, American lawyer and politician
 * 1955  – Michael Callen, American singer-songwriter and AIDS activist (d. 1993)
 * 1955  – Micheal Ray Richardson, American basketball player and coach
 * 1958 – Stuart Adamson, Scottish singer-songwriter and guitarist (d. 2001)
 * 1958  – Lyudmila Kondratyeva, Russian sprinter
 * 1958  – Wayne Wigham, Australian rugby league player
 * 1959 – Pierre Lacroix, Canadian ice hockey player
 * 1959  – Ana María Polo, Cuban-American lawyer and judge
 * 1959  – Zahid Maleque, Bangladeshi politician
 * 1960 – Jeremy Clarkson, English journalist and television presenter
 * 1961 – Vincent Gallo, American actor, director, producer, and musician
 * 1961  – Doug Hopkins, American guitarist and songwriter (d. 1993)
 * 1961  – Nobuaki Kakuda, Japanese martial artist
 * 1962 – Franck Ducheix, French fencer
 * 1962  – Mark Lawson, English journalist and author
 * 1963 – Billy Bowden, New Zealand cricketer and umpire
 * 1963  – Waldemar Fornalik, Polish footballer and manager
 * 1963  – Elizabeth Smylie, Australian tennis player
 * 1963  – Eleni Tsaligopoulou, Greek singer
 * 1964 – Steve Azar, American singer-songwriter and guitarist
 * 1964  – John Cryer, English journalist and politician
 * 1964  – Johann Sebastian Paetsch, American cellist
 * 1964  – Bret Saberhagen, American baseball player and coach
 * 1964  – Patrick Sang, Kenyan runner
 * 1966 – Steve Scarsone, American baseball player and manager
 * 1966  – Shin Seung-hun, South Korean singer-songwriter
 * 1966  – Lisa Stansfield, English singer-songwriter and actress
 * 1968 – Sergei Lukyanenko, Kazakh-Russian journalist and author
 * 1969 – Cerys Matthews, Welsh singer-songwriter
 * 1969  – Dustin Rhodes, American wrestler
 * 1969  – Michael von Grünigen, Swiss skier
 * 1970 – Trevor Linden, Canadian ice hockey player and manager
 * 1970 – Whigfield, Danish singer and songwriter
 * 1971 – Oliver Riedel, German bass player
 * 1972 – Balls Mahoney, American wrestler (d. 2016)
 * 1972  – Allan Théo, French singer
 * 1972  – Jason Varitek, American baseball player and manager
 * 1972  – Jennifer Esposito, American actress and writer
 * 1973 – Olivier Magne, French rugby player
 * 1974 – Àlex Corretja, Spanish tennis player and coach
 * 1974  – Ashot Danielyan, Armenian weightlifter
 * 1974  – David Jassy, Swedish singer-songwriter and producer
 * 1974  – Tom Thacker, Canadian singer-songwriter, guitarist, and producer
 * 1974  – Trot Nixon, American baseball player and sportscaster
 * 1976 – Marta Breen, Norwegian journalist, non-fiction writer, and organizational leader
 * 1976  – Kelvim Escobar, Venezuelan baseball player
 * 1976  – Kotomitsuki Keiji, Japanese sumo wrestler
 * 1977 – Ivonne Teichmann, German runner
 * 1978 – Josh Hancock, American baseball player (d. 2007)
 * 1979 – Malcolm Christie, English footballer
 * 1979  – Sebastien Grainger, Canadian singer-songwriter and guitarist
 * 1979  – Michel Riesen, Swiss ice hockey player
 * 1979  – Josh Server, American actor
 * 1980 – Keiji Tamada, Japanese footballer
 * 1980  – Mark Teixeira, American baseball player
 * 1981 – Alessandra Ambrosio, Brazilian model
 * 1981  – Alexandre Burrows, Canadian ice hockey player
 * 1981  – Luis Flores, Dominican basketball player
 * 1981  – Veronica Pyke, Australian cricketer
 * 1982 – Ian Bell, English cricketer
 * 1982  – Peeter Kümmel, Estonian skier
 * 1983 – Jennifer Heil, Canadian skier
 * 1983  – Rubén Palazuelos, Spanish footballer
 * 1983  – Nicky Pastorelli, Dutch race car driver
 * 1984 – Kelli Garner, American actress
 * 1984  – Nikola Karabatić, French handball player
 * 1985 – Pablo Hernández Domínguez, Spanish footballer
 * 1985  – Will Minson, Australian footballer
 * 1986 – Sarodj Bertin, Haitian model and human rights lawyer
 * 1986  – Lena Schöneborn, German pentathlete
 * 1987 – Joss Stone, English singer-songwriter and actress
 * 1987  – Lights, Canadian singer-songwriter
 * 1988 – Leland Irving, Canadian ice hockey player
 * 1989  – Torrin Lawrence, American sprinter (d. 2014)
 * 1990 – Dimitrios Anastasopoulos, Greek footballer
 * 1990  – Thulani Serero, South African footballer
 * 1991 – Thiago Alcântara, Spanish footballer
 * 1991  – Brennan Poole, American racing driver
 * 1994 – Brandon Montour, Canadian ice hockey player
 * 1996 – Dele Alli, English international footballer
 * 2000 – Calen Addison, Canadian ice hockey player
 * 2000  – Milly Alcock, Australian actress
 * 2001 – Manuel Ugarte, Uruguayan footballer
 * 2002 – Jake Fraser-McGurk, Australian cricketer

Pre-1600

 * 618 – Yang Guang, Chinese emperor of the Sui Dynasty (b. 569)
 * 678 – Donus, pope of the Catholic Church (b. 610)
 * 924 – Herman I, chancellor and archbishop of Cologne
 * 1034 – Romanos III Argyros, Byzantine emperor (b. 968)
 * 1077 – Anawrahta, king of Burma and founder of the Pagan Empire (b. 1014)
 * 1079 – Stanislaus of Szczepanów, bishop of Kraków (b. 1030)
 * 1165 – Stephen IV, king of Hungary and Croatia
 * 1240 – Llywelyn the Great, Welsh prince (b. 1172)
 * 1349 – Ramadan ibn Alauddin, first known Muslim from Korea
 * 1447 – Henry Beaufort, Cardinal, Lord Chancellor of England (b. 1377)
 * 1512 – Gaston de Foix, French military commander (b. 1489)
 * 1554 – Thomas Wyatt the Younger, English rebel leader (b. 1521)
 * 1587 – Thomas Bromley, English lord chancellor (b. 1530)

1601–1900

 * 1609 – John Lumley, 1st Baron Lumley, English noble (b. 1533)
 * 1612 – Emanuel van Meteren, Flemish historian and author (b. 1535)
 * 1612  – Edward Wightman, English minister and martyr (b. 1566)
 * 1626 – Marino Ghetaldi, Ragusan mathematician and physicist (b. 1568)
 * 1712 – Richard Simon, French priest and critic (b. 1638)
 * 1723 – John Robinson, English bishop and diplomat (b. 1650)
 * 1783 – Nikita Ivanovich Panin, Polish-Russian politician, Russian Minister of Foreign Affairs (b. 1718)
 * 1798 – Karl Wilhelm Ramler, German poet and academic (b. 1725)
 * 1856 – Juan Santamaría, Costa Rican soldier (b. 1831)
 * 1861 – Francisco González Bocanegra, Mexican poet and composer (b. 1824)
 * 1873 – Edward Canby, American general (b. 1817)
 * 1890 – David de Jahacob Lopez Cardozo, Dutch Talmudist (b. 1808)
 * 1890  – Joseph Merrick, English man with severe deformities (b. 1862)
 * 1894 – Constantin Lipsius, German architect and theorist (b. 1832)
 * 1895 – Julius Lothar Meyer, German chemist (b. 1830)

1901–present

 * 1902 – Wade Hampton III, Confederate general and politician, 77th Governor of South Carolina (b. 1818)
 * 1903 – Gemma Galgani, Italian mystic and saint (b. 1878)
 * 1906 – James Anthony Bailey, American businessman, co-founded Ringling Bros. and Barnum & Bailey Circus (b. 1847)
 * 1906  – Francis Pharcellus Church, American journalist and publisher, co-founded Armed Forces Journal and The Galaxy Magazine (b. 1839)
 * 1908 – Henry Bird, English chess player and author (b. 1829)
 * 1916 – Richard Harding Davis, American journalist and author (b. 1864)
 * 1918 – Otto Wagner, Austrian architect and urban planner (b. 1841)
 * 1926 – Luther Burbank, American botanist and academic (b. 1849)
 * 1939 – Kurtdereli Mehmet, Turkish wrestler (b. 1864)
 * 1953 – Kid Nichols, American baseball player and manager (b. 1869)
 * 1954 – Paul Specht, American violinist and bandleader (b. 1895)
 * 1958 – Konstantin Yuon, Russian painter and educator (b. 1875)
 * 1960 – Rosa Grünberg, Swedish actress (b. 1878)
 * 1962 – Ukichiro Nakaya, Japanese physicist and academic (b. 1900)
 * 1962  – George Poage, American hurdler and educator (b. 1880)
 * 1962  – Axel Revold, Norwegian painter (b. 1887)
 * 1967 – Thomas Farrell, American general (b. 1891)
 * 1967  – Donald Sangster, Jamaican lawyer and politician, 2nd Prime Minister of Jamaica (b. 1911)
 * 1970 – Cathy O'Donnell, American actress (b. 1923)
 * 1970  – John O'Hara, American novelist and short story writer (b. 1905)
 * 1974 – Ernst Ziegler, German actor (b. 1894)
 * 1977 – Jacques Prévert, French poet and screenwriter (b. 1900)
 * 1977  – Phanishwar Nath 'Renu', Indian author and activist (b. 1921)
 * 1980 – Ümit Kaftancıoğlu, Turkish journalist and producer (b. 1935)
 * 1981 – Caroline Gordon, American author and critic (b. 1895)
 * 1983 – Dolores del Río, Mexican actress (b. 1904)
 * 1984 – Edgar V. Saks, Estonian historian and politician, Estonian Minister of Education (b. 1910)
 * 1985 – Bunny Ahearne, Irish-born English businessman (b. 1900)
 * 1985  – John Gilroy, English artist and illustrator (b. 1898)
 * 1985  – Enver Hoxha, Albanian educator and politician, 21st Prime Minister of Albania (b. 1908)
 * 1987 – Erskine Caldwell, American novelist and short story writer (b. 1903)
 * 1987  – Primo Levi, Italian chemist and author (b. 1919)
 * 1990 – Harold Ballard, Canadian businessman (b. 1903)
 * 1991 – Walker Cooper, American baseball player and manager (b. 1915)
 * 1991  – Bruno Hoffmann. German glass harp player (b. 1913)
 * 1992 – James Brown, American actor and singer (b. 1920)
 * 1992  – Eve Merriam, American author and poet (b. 1916)
 * 1992  – Alejandro Obregón, Colombian painter, sculptor, and engraver (b. 1920)
 * 1996 – Jessica Dubroff, American pilot (b. 1988)
 * 1997 – Muriel McQueen Fergusson, Canadian lawyer and politician, Canadian Speaker of the Senate (b. 1899)
 * 1997  – Wang Xiaobo, contemporary Chinese novelist and essayist (b. 1952)
 * 1999 – William H. Armstrong, American author and educator (b. 1911)
 * 2000 – Diana Darvey, English actress, singer and dancer (b. 1945)
 * 2001 – Harry Secombe, Welsh-English actor (b. 1921)
 * 2003 – Cecil Howard Green, English-American geophysicist and businessman, founded Texas Instruments (b. 1900)
 * 2005 – André François, Romanian-French cartoonist, painter, and sculptor (b. 1915)
 * 2005  – Lucien Laurent, French footballer and coach (b. 1907)
 * 2006 – June Pointer, American singer (b. 1953)
 * 2006  – DeShaun Holton, American rapper and actor (b. 1973)
 * 2007 – Roscoe Lee Browne, American actor and director (b. 1922)
 * 2007  – Loïc Leferme, French diver (b. 1970)
 * 2007  – Janet McDonald, American lawyer and author (b. 1954)
 * 2007  – Ronald Speirs, Scottish-American colonel (b. 1920)
 * 2007  – Kurt Vonnegut, American novelist, short story writer, and playwright (b. 1922)
 * 2008 – Merlin German, American sergeant (b. 1985)
 * 2009 – Gerda Gilboe, Danish actress and singer (b. 1914)
 * 2009  – Vishnu Prabhakar, Indian author and playwright (b. 1912)
 * 2009  – Corín Tellado, Spanish author (b. 1927)
 * 2010 – Julia Tsenova, Bulgarian pianist and composer (b. 1948)
 * 2011 – Larry Sweeney, American wrestler and manager (b. 1981)
 * 2012 – Ahmed Ben Bella, Algerian soldier and politician, 1st President of Algeria (b. 1916)
 * 2012  – Roger Caron, Canadian criminal and author (b. 1938)
 * 2012  – Tippy Dye, American basketball player and coach (b. 1915)
 * 2012  – Hal McKusick, American saxophonist, clarinet player, and flute player (b. 1924)
 * 2012  – Agustin Roman, American bishop (b. 1928)
 * 2013 – Don Blackman, American singer-songwriter, pianist, and producer (b. 1953)
 * 2013  – Sue Draheim, American fiddler (b.1949)
 * 2013  – Grady Hatton, American baseball player, coach, and manager (b. 1922)
 * 2013  – Thomas Hemsley, English actor and singer (b. 1927)
 * 2013  – Hilary Koprowski, Polish-American virologist and immunologist (b. 1916)
 * 2013  – Gilles Marchal, French singer-songwriter (b. 1944)
 * 2013  – Maria Tallchief, American ballerina (b. 1925)
 * 2013  – Clorindo Testa, Italian-Argentinian architect (b. 1923)
 * 2013  – Jonathan Winters, American comedian, actor and screenwriter (b. 1925)
 * 2014 – Rolf Brem, Swiss sculptor and illustrator (b. 1926)
 * 2014  – Edna Doré, English actress (b. 1921)
 * 2014  – Bill Henry, American baseball player (b. 1927)
 * 2014  – Lou Hudson, American basketball player and sportscaster (b. 1944)
 * 2014  – Myer S. Kripke, American rabbi and scholar (b. 1914)
 * 2014  – Sergey Nepobedimy, Russian engineer (b. 1921)
 * 2014  – Jesse Winchester, American singer-songwriter, guitarist, and producer (b. 1944)
 * 2015 – Jimmy Gunn, American football player (b. 1948)
 * 2015  – Muhammad Kamaruzzaman, Bangladeshi journalist and politician (b. 1952)
 * 2015  – François Maspero, French journalist and author (b. 1932)
 * 2015  – Hanut Singh, Indian general (b. 1933)
 * 2015  – Tekena Tamuno, Nigerian historian and academic (b. 1932)
 * 2017 – J. Geils, American singer and guitarist (b. 1946)
 * 2017  – Mark Wainberg, Canadian researcher and HIV/AIDS activist (b. 1945)
 * 2020 – John Horton Conway, English mathematician (b. 1937)
 * 2024 – Park Bo-ram, South Korean singer (b. 1994)

Holidays and observances

 * Christian feast day:
 * Antipas of Pergamum (Greek Orthodox Church)
 * Barsanuphius
 * Gemma Galgani
 * Godeberta
 * Guthlac of Crowland
 * George Selwyn (Anglicanism)
 * Stanislaus of Szczepanów
 * April 11 (Eastern Orthodox liturgics)
 * Juan Santamaría Day, anniversary of his death in the Second Battle of Rivas. (Costa Rica)
 * International Louie Louie Day
 * World Parkinson's Day

title: April 11