Essentially, the stator or reference portion of the pickoff is established with respect to the true heading direction, and the platform is turned either manually or automatically until the angular electrical pickoff signal is reduced to zero.

Non-coherent modulation methods do not require a receiver reference clock signal that is phase synchronized with the sender carrier wave.

The time difference between two clocks may be determined by simultaneously comparing each clock to a common reference signal that may be received at both sites.

If one of the two events represents the sending of a signal from one location and the second event represents the reception of the same signal at another location, then as long as the signal is moving at the speed of light or slower, the mathematics of simultaneity ensures that all reference frames agree that the transmission-event happened before the reception-event.

These limits correspond to the reference signal ( red ), offset by a given value.

In telecommunications, a fading distribution is the probability distribution of the value of signal fading relative to a specified reference level.

A genlock signal is required to provide a means for video synchronizing with the house reference.

This allows extremely narrow band detection ( much narrower than any possible color filter can achieve ) as well as precision measurements of phase and frequency of a light signal relative to a reference light source, as in Laser Doppler Vibrometry.

Jitter is the undesired deviation from true periodicity of an assumed periodic signal in electronics and telecommunications, often in relation to a reference clock source.

A phase-locked loop or phase lock loop ( PLL ) is a control system that generates an output signal whose phase is related to the phase of an input " reference " signal.

Phase-shift keying ( PSK ) is a digital modulation scheme that conveys data by changing, or modulating, the phase of a reference signal ( the carrier wave ).

This requires the receiver to be able to compare the phase of the received signal to a reference signal — such a system is termed coherent ( and referred to as CPSK ).

In this system, the demodulator determines the changes in the phase of the received signal rather than the phase ( relative to a reference wave ) itself.

DPSK can be significantly simpler to implement than ordinary PSK since there is no need for the demodulator to have a copy of the reference signal to determine the exact phase of the received signal ( it is a non-coherent scheme ).

* By viewing the phase itself as conveying the information, in which case the demodulator must have a reference signal to compare the received signal's phase against ; or

In telecommunication, relative transmission level is the ratio of the signal power, at a given point in a transmission system, to a reference signal power.

In analog ( usually audio ) systems, reduction of the dynamic range of a signal by controlling it as a function of the inverse relationship of its instantaneous value relative to a specified reference level.

Instantaneous values of the input signal that are low, relative to the reference level, are increased, and those that are high are decreased.

Due to its graphical user inferface, it was known as the " Jackintosh ", a reference to Jack Tramiel.

The latter includes El Passionato, Kigmyland, The Republic of Crumbumbo, Skunk Hollow, The Valley of the Shmoon, Planets Pincus Number 2 and 7, and a miserable frozen wasteland known as Lower Slobbovia, a pointedly political satire of backward nations and foreign diplomacy that remains a contemporary reference.

20 ) contains earliest known reference to Latrunculi ( often confused with Ludus Duodecim Scriptorum, Ovid's game mentioned below ).

* 1 BC – 8 AD: Ovid's Ars Amatoria contains earliest known reference to Ludus Duodecim Scriptorum.

" In a reference to the first known historical Boii, Polybius relates that their wealth consisted of cattle and gold, that they depended on agriculture and war, and that a man's status depended on the number of associates and assistants he had.

It is also known as the Book of the Revelation of Saint John the Divine or the Apocalypse of John, ( both in reference to its author ) or the Book of the Revelation of Jesus Christ ( in reference to its opening line ) or simply Revelation, ( often erroneously called Revelations in contrast to the singular in the original Koine ) or the Apocalypse.

The World Factbook ( ISSN ; also known as the CIA World Factbook ) is a reference resource produced by the Central Intelligence Agency of the United States with almanac-style information about the countries of the world.

The game, first known as crapaud ( a French word meaning " toad " in reference to the original style of play by people crouched over a floor or sidewalk ), reportedly owes its modern popularity to street craps.

The earliest known reference to croquet in Scotland is the booklet called The Game of Croquet, its Laws and Regulations which was published in the mid-1860s for the proprietor of Eglinton Castle, the Earl of Eglinton.

Cerberus featured in many prominent works of Greek and Roman literature, most famously in Virgil's Aeneid, Peisandros of Rhodes ' epic poem the Labours of Hercules, the story of Orpheus in Plato's Symposium, and in Homer's Iliad, which is the only known reference to one of Heracles ' labours which first appeared in a literary source.

The first known reference to the site of the current city of Chicago as " Checagou " was by Robert de LaSalle around 1679 in a memoir written about the time.

He is often known as Constantine I, in reference to his place in modern lists of kings of Scots, though contemporary sources described Causantín only as a Pictish king.

The first known reference to one was by Johann Speth in 1693 and the earliest such extant signed and dated clavichord was built in 1716 by Johann Michael Heinitz.

Therefore, equatorial coordinates ( including declination ) are inherently relative to the year of their observation, and astronomers specify them with reference to a particular year, known as an epoch.

The plane of the Earth's orbit projected in all directions forms the reference plane known as the ecliptic.

Not a lot is known of Jude, which would explain the apparent need to identify him by reference to his better-known brother.

However, the topography other than coastlines and major rivers is quite different, and the only apparent reference to the real world besides the map may be the Blood Wood, known as " Wyrm Wood " before the Scourge and similar in location and extent to the Chernobyl ( Ukrainian for " wormwood ") Zone of alienation.

One of these is the famous work Saturn Devouring His Son ( known informally in some circles as Devoration or Saturn Eats His Child ), which displays a Greco-Roman mythological scene of the god Saturn consuming a child, possibly a reference to Spain's ongoing civil conflicts.

In the Star Trek episode " The Ultimate Computer ", Dr. McCoy refers to an alcoholic drink known as the " Finagle's Folly ," apparently a reference to " Finagle's Law.

His book includes the earliest known reference to roux using pork fat.

In antiquity, the island was known as Planaria, among other names, in reference to the flatness of most of its landscape.

The generalization of this statement, namely that the laws of special relativity hold to good approximation in freely falling ( and non-rotating ) reference frames, is known as the Einstein equivalence principle, a crucial guiding principle for generalizing special-relativistic physics to include gravity.

Except for Irenaeus ' 2nd-century reference to many in the church speaking all kinds of languages ' through the Spirit ', and Tertullian's reference in 207 AD to the spiritual gift of interpretation of tongues being encountered in his day, there are no other known first-hand accounts of glossolalia, and very few second-hand accounts among their writings.