query: the common name for a modulator demodulator is

pos: Modem Modem A modem (portmanteau of modulator-demodulator) is a hardware device that converts data so that it can be transmitted from computer to computer over telephone wires. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data. Modems can be used with any means of transmitting analog signals, from light-emitting diodes to radio. A common type of modem is one that turns the digital data of a computer into modulated electrical signal for transmission over telephone lines and demodulated by another modem at the receiver side to recover the digital data.

pos: Modulation into a moderate to high frequency range passband signal, one that can pass through a filter. A modulator is a device that performs modulation. A demodulator (sometimes "detector" or "demod") is a device that performs demodulation, the inverse of modulation. A modem (from modulator–demodulator) can perform both operations. The aim of analog modulation is to transfer an analog baseband (or lowpass) signal, for example an audio signal or TV signal, over an analog bandpass channel at a different frequency, for example over a limited radio frequency band or a cable TV network channel. The aim of digital modulation is to

pos: Modem Modem A modem (portmanteau of modulator-demodulator) is a hardware device that converts data so that it can be transmitted from computer to computer over telephone wires. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data. Modems can be used with any means of transmitting analog signals, from light-emitting diodes to radio. A common type of modem is one that turns the digital data of a computer into modulated electrical signal for transmission over telephone lines and demodulated by another modem at the receiver side to recover the digital data.

pos: Modem They are used for telephony applications. See voice modem command set for more details on voice modems. This type of modem can be used as an FXO card for private branch exchange (PBX) systems (compare V.92). Modem A modem (portmanteau of modulator-demodulator) is a hardware device that converts data so that it can be transmitted from computer to computer over telephone wires. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data. Modems can be used with any means of transmitting analog signals, from light-emitting diodes to radio. A common

pos: Codec compander functions. A modem is a contraction of "modulator-demodulator". The telecommunications industry referred to the device as a "dataset". It converts digital data from computers to analog signals for transmission over telephone lines. On the receiving end the analog signal is converted back to digital data. An audio codec converts analog audio signals into digital signals for transmission or encodes them for storage. A receiving device converts the digital signals back to analog form using an audio decoder for playback. An example of this are the codecs used in the sound cards of personal computers. A video codec accomplishes the

pos: Satellite modem are two different types, both employing the Digital Video Broadcasting (DVB) standard as their basis: There are also industrial satellite modems intended to provide a permanent link. They are used, for example, in the Steel shankar network. Satellite modem A satellite modem or satmodem is a modem used to establish data transfers using a communications satellite as a relay. A satellite modem's main function is to transform an input bitstream to a radio signal and vice versa. There are some devices that include only a demodulator (and no modulator, thus only allowing data to be downloaded by satellite) that are

pos: Satellite modem Satellite modem A satellite modem or satmodem is a modem used to establish data transfers using a communications satellite as a relay. A satellite modem's main function is to transform an input bitstream to a radio signal and vice versa. There are some devices that include only a demodulator (and no modulator, thus only allowing data to be downloaded by satellite) that are also referred to as "satellite modems." These devices are used in satellite Internet access (in this case uploaded data is transferred through a conventional PSTN modem or an ADSL modem). A satellite modem is not the only

pos: Modem address translation (NAT) router, Ethernet switch, WiFi access point, DHCP server, firewall, among others. Some residential gateway offer a so-called "bridged mode", which disables the built-in routing function and makes the device function similarly to a plain modem. This bridged mode is separate from RFC 1483 bridging. Modems that are used to connect to a fiber optic network are known as optical network units (ONUs). Fiber optic systems can be upgraded by the use of quadrature amplitude modulation. The modulator and demodulator are separate components rather than a single assembly as with most modems. 16QAM uses a 16-point constellation to

pos: Vanguard Managed Solutions a government contractor headquartered in Newton, Massachusetts. In May 1967, Codex acquired Teldata, a small company led by Jerry Holsinger that was developing data communication products that would operate at data rates of 9600 bit per second compared to the 1200 bit per second rate of existing products. Robert G. Gallager was hired as a consultant, and convinced the company to develop quadrature amplitude modulation techniques using two sidebands instead of single-sideband modulation. This technique was later refined by Dave Forney (hired in 1965) into a successful modem (modulator and demodulator) product. Within a few years it had about 20%

pos: Arthur A. Collins in 1955 up to 40 channels compared to one voice or data channel in the same bandwidth with conventional telephone service. A key component of KINEPLEX was the world's first practical, mass-produced MODEM (modulator/demodulator), in essence a translator between binary and analog signals. The classified Collins Navy Tactical Data System (NTDS) derived from this work. Arthur Collins was among the first to predict the coming computer and telecommunication revolution, and led his engineers to combine the lessons of KINEPLEX with communication expertise to establish in the early 1960s a data and message switching facility in Cedar Rapids, using Collins C8400

pos: Fax demodulator an image without first negotiating a connection with a receiving modem. Fax demodulator A fax demodulator is a device used to intercept fax messages by listening in on a telephone line or radio signal. A typical (Group III) fax transmission requires a two-way conversation between two modems (that is, each participant must both transmit and receive). Each modem may be part of a “fax machine” incorporating an image scanner and a printer. A demodulator can only be used to observe a conversation between two fax modems, usually to record the image transmitted. It cannot be used to receive a fax

pos: Fax demodulator Fax demodulator A fax demodulator is a device used to intercept fax messages by listening in on a telephone line or radio signal. A typical (Group III) fax transmission requires a two-way conversation between two modems (that is, each participant must both transmit and receive). Each modem may be part of a “fax machine” incorporating an image scanner and a printer. A demodulator can only be used to observe a conversation between two fax modems, usually to record the image transmitted. It cannot be used to receive a fax transmission in the usual sense, because a sending modem cannot transmit

pos: Demodulation Demodulation Demodulation is extracting the original information-bearing signal from a carrier wave. A demodulator is an electronic circuit (or computer program in a software-defined radio) that is used to recover the information content from the modulated carrier wave. There are many types of modulation so there are many types of demodulators. The signal output from a demodulator may represent sound (an analog audio signal), images (an analog video signal) or binary data (a digital signal). These terms are traditionally used in connection with radio receivers, but many other systems use many kinds of demodulators. For example, in a modem, which

neg: Modulation demodulator must be done simultaneously. Digital modulation schemes are possible because the transmitter-receiver pair has prior knowledge of how data is encoded and represented in the communications system. In all digital communication systems, both the modulator at the transmitter and the demodulator at the receiver are structured so that they perform inverse operations. Non-coherent modulation methods do not require a receiver reference clock signal that is phase synchronized with the sender carrier signal. In this case, modulation symbols (rather than bits, characters, or data packets) are asynchronously transferred. The opposite is coherent modulation. The most common digital modulation techniques are:

neg: Modulation symbol. PSK and ASK, and sometimes also FSK, are often generated and detected using the principle of QAM. The I and Q signals can be combined into a complex-valued signal "I"+"jQ" (where "j" is the imaginary unit). The resulting so called equivalent lowpass signal or equivalent baseband signal is a complex-valued representation of the real-valued modulated physical signal (the so-called passband signal or RF signal). These are the general steps used by the modulator to transmit data: At the receiver side, the demodulator typically performs: As is common to all digital communication systems, the design of both the modulator and

neg: Satellite modem signal on Intermediate frequency (IF). A modulator is generally a much simpler device than a demodulator, because it doesn't have to recover symbol and carrier frequencies. A demodulator is one of the most important parts of the receiver. The exact structure of the demodulator is defined by a modulation type. However, the fundamental concepts are similar. Moreover, it is possible to develop a demodulator which can process signals with different modulation types. Digital demodulation implies that a "symbol clock" (and, in most cases, an intermediate frequency generator) at the receiving side have to be synchronous with those at the transmitting

neg: Product detector in a way much like a single-sideband modulator. Two copies of the modulated input signals are created. The first copy is mixed with a local oscillator and low-pass filtered. The second copy is mixed with a 90° phase-shifted copy of the oscillator and the output of this mixer is also 90° phase-shifted and then low-pass filtered. These copies are then combined to produce the original message. This operation is similar to that performed by a dual-phase lock-in amplifier. Example: I-Q Demodulator The product demodulator has some advantages over an envelope detector for AM signal reception. On the other hand, the

neg: Phase-shift keying is represented by the particular phase. The demodulator, which is designed specifically for the symbol-set used by the modulator, determines the phase of the received signal and maps it back to the symbol it represents, thus recovering the original data. 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). CPSK requires a complicated demodulator, because it must extract the reference wave from the received signal and keep track of it, to compare each sample to. Alternatively, the phase shift

neg: Ring modulation If the left carrier terminal is positive, the top and bottom diodes conduct. If that terminal is negative, then the side diodes conduct, but create a polarity inversion between the transformers. This action is much like that of a DPDT ("double pole, double throw") switch wired for reversing connections. (See also Integrated circuit methods of ring modulation) A particular elegance of the ring modulator is that it is bidirectional: the signal flow can be reversed allowing the same circuit with the same carrier to be used either as a modulator or demodulator, for example in low-cost radio transceivers. On the

neg: Demodulation is a contraction of the terms modulator/demodulator, a demodulator is used to extract a serial digital data stream from a carrier signal which is used to carry it through a telephone line, coaxial cable, or optical fiber. Demodulation was first used in radio receivers. In the wireless telegraphy radio systems used during the first 3 decades of radio (1884-1914) the transmitter did not communicate audio (sound) but transmitted information in the form of pulses of radio waves that represented text messages in Morse code. Therefore, the receiver merely had to detect the presence or absence of the radio signal, and

neg: Ring modulation telephone and wireless networking systems. In this case, the circuit is sometimes called a "ring demodulator", one of many possible chopper circuits. A ring modulator can be used to generate a double-sideband suppressed-carrier (DSB-SC) wave used in radio transmission. The original application of the ring modulator was for combining multiple analogue telephone voice channels into a single wideband signal to be carried on a single cable using frequency-division multiplexing. Early attempts at securing analogue telephone channels used ring modulators to modify the spectrum of the audio speech signals. One application is spectral inversion, typically of speech; a carrier frequency is

neg: Ring modulation chosen to be above the highest speech frequencies (which are low-pass filtered at, say, 3 kHz, for a carrier of perhaps 3.3 kHz), and the sum frequencies from the modulator are removed by more low-pass filtering. The remaining difference frequencies have an inverted spectrum—High frequencies become low, and vice versa. Ring modulation has also been extensively used in radio receivers, for example to demodulate an FM stereo signal, and to down-convert microwave signals in mobile telephone and wireless networking systems. In this case, the circuit is sometimes called a "ring demodulator", one of many possible chopper circuits. A ring modulator

neg: Photoelastic modulator a phase-sensitive detector, the demodulator. The amplitude of oscillation is adjusted by an external applied voltage that is proportional to the wavelength of the light passing through the modulator. A typical polarimetric setup consists of two linear polarizers forming a crossed analyzer setup, an optical sample introducing the change in the polarization of light, and a PEM further modulating the polarization state. The final detected intensities at the fundamental and second harmonic of PEM operating frequency depend on the ellipticity and rotation introduced by the sample. PEM polarimetry has the advantage that the signal is modulated at a high frequency

neg: Fax drum. The reflected light, varying in intensity according to the light and dark areas of the document, was focused on a photocell so that the current in a circuit varied with the amount of light. This current was used to control a tone generator (a modulator), the current determining the frequency of the tone produced. This audio tone was then transmitted using an acoustic coupler (a speaker, in this case) attached to the microphone of a common telephone handset. At the receiving end, a handset’s speaker was attached to an acoustic coupler (a microphone), and a demodulator converted the varying

neg: Single-sideband modulation the envelope term; roughly half the modulation term applied to the envelope modulator is utilized to reduce the second-order term of the arcsin "phase"-modulated path; thus reducing the second-order term in the undesired sideband. A multi-loop modulator/demodulator feedback approach was used to generate an accurate arcsin signal. This approach was introduced in 1984 and became known as the STR-84 method. It was sold by Kahn Research Laboratories; later, Kahn Communications, Inc. of NY. An additional audio processing device further improved the sideband structure by selectively applying pre-emphasis to the modulating signals. Since the envelope of all the signals described remains

neg: Computer network interface, also known as the "black hole" interface because data can go into it, however, no further processing is done for said data, i.e. the packets are dropped. Modems (MOdulator-DEModulator) are used to connect network nodes via wire not originally designed for digital network traffic, or for wireless. To do this one or more carrier signals are modulated by the digital signal to produce an analog signal that can be tailored to give the required properties for transmission. Modems are commonly used for telephone lines, using a Digital Subscriber Line technology. A firewall is a network device for controlling network

neg: Network topology interface because data can go into it, however, no further processing is done for said data, i.e. the packets are dropped. Modems (MOdulator-DEModulator) are used to connect network nodes via wire not originally designed for digital network traffic, or for wireless. To do this one or more carrier signals are modulated by the digital signal to produce an analog signal that can be tailored to give the required properties for transmission. Modems are commonly used for telephone lines, using a Digital Subscriber Line technology. A firewall is a network device for controlling network security and access rules. Firewalls are typically

neg: Underwater acoustic communication bits forms the symbol that is represented by the particular phase. The demodulator, which is designed specifically for the symbol-set used by the modulator, determines the phase of the received signal and maps it back to the symbol it represents, thus recovering the original data. 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). Alternatively, instead of operating with respect to a constant reference wave, the broadcast can operate with respect to itself. Changes in phase of a

neg: Yaesu FT-7(B) configuration with premix heterodyne techniques reducing signal distortion in transmit and receive mode. The incoming signal goes via an antenna relay, tuning circuit, to a RF amplifier, passband tuning unit and mixer. The signal is filtered and fed to the audio amplifier and translated into a 3W audio signal. The outgoing signal is going from the microphone via the modulator / demodulator unit to a filter. Then it is amplified and heterodyned, mixed and fed to the final amplifier. Yaesu FT-7(B) Yaesu FT-7 is a rugged, solid state and modular built HF amateur-band radio transceiver, suitable for fixed and for

neg: Phase-shift keying complex carrier-recovery schemes to provide an accurate phase estimate and can be an attractive alternative to ordinary PSK. In optical communications, the data can be modulated onto the phase of a laser in a differential way. The modulation is a laser which emits a continuous wave, and a Mach-Zehnder modulator which receives electrical binary data. For the case of BPSK, the laser transmits the field unchanged for binary '1', and with reverse polarity for '0'. The demodulator consists of a delay line interferometer which delays one bit, so two bits can be compared at one time. In further processing, a

neg: Amateur radio repeater slow-scan television signals. A typical SSTV repeater is equipped with a HF or VHF transceiver and a computer with a sound card, which serves as a demodulator/modulator of SSTV signals. SSTV repeaters are used by amateur radio operators for exchanging pictures. If two stations cannot copy each other, they can still communicate through a repeater. One type of SSTV repeater is activated by a station sending it a 1750 Hz tone. The repeater sends K in morse code to confirm its activation, after which the station must start sending a picture within about 10 seconds. After reception, the received image

neg: DTV receiver the demultiplexer. The modulator reverses the actions of a demodulator and its function is to deliver a signal to the return path tuner. The technology used in DTV television is MPEG-2. The demultiplexer selects particular packets, decrypts, and forwards to a specific decoder. A DTV receiver will normally contain three separate decoders for converting the digital bit-stream back into a format that can be heard and viewed by the subscriber. A video decoder’’’ It transforms video packets into a sequence of pictures, which are displayed by the TV monitor. An audio decoder’’’ It decompresses the audio bit-stream. Different audio modes

neg: Orthogonal frequency-division multiplexing WCP-OFDM ("Weighted Cyclic Prefix Orthogonal Frequency-Division Multiplexing") consists of using short filters at the transmitter output in order to perform a potentially non-rectangular pulse shaping and a near perfect reconstruction using a single-tap per subcarrier equalization. Other ICI suppression techniques usually increase drastically the receiver complexity. The orthogonality allows for efficient modulator and demodulator implementation using the FFT algorithm on the receiver side, and inverse FFT on the sender side. Although the principles and some of the benefits have been known since the 1960s, OFDM is popular for wideband communications today by way of low-cost digital signal processing components that

neg: Amplitude-shift keying binary digits. Usually, each amplitude encodes an equal number of bits. Each pattern of bits forms the symbol that is represented by the particular amplitude. The demodulator, which is designed specifically for the symbol-set used by the modulator, determines the amplitude of the received signal and maps it back to the symbol it represents, thus recovering the original data. Frequency and phase of the carrier are kept constant. Like AM, an ASK is also linear and sensitive to atmospheric noise, distortions, propagation conditions on different routes in PSTN, etc. Both ASK modulation and demodulation processes are relatively inexpensive. The ASK

neg: Telemedicine Medical college by Ajai Shanker, S. Makhija, P.K. Mantri using an indigenous technique for the first time in India. This system enabled wireless transmission of ECG from the moving ICU van or the patients home to the central station in ICU of the department of Medicine. Transmission using wireless was done using frequency modulation which eliminated noise. Transmission was also done through telephone lines. The ECG output was connected to the telephone input using a modulator which converted ECG into high frequency sound. At the other end a demodulator reconverted the sound into ECG with a good gain accuracy. The

neg: International Cometary Explorer if they got the spacecraft to change its orbit by late May or early June 2014, or in early July by using more fuel, it could use the Moon's gravity to get back into a useful halo orbit. Earlier in 2014, officials with the Goddard Space Flight Center said the Deep Space Network equipment necessary to transmit signals to the spacecraft had been decommissioned in 1999, and was too expensive to replace. However, project members were able to find documentation for the original equipment and were able to simulate the complex modulator/demodulator electronics using modern software-defined radio (SDR) techniques and

neg: Wireless identification and sensing platform reporting that sensor data back to the RFID reader. WISPs have been built with light sensors, temperature sensors, and strain gauges. Some contain accelerometers. WISPs can write to flash and perform cryptographic computations. The WISP was originally developed by Intel Research Seattle, but after their closure development work has continued at the Sensor Systems Laboratory at the University of Washington in Seattle. The WISP consists of a board with power harvesting circuitry, demodulator, modulator, microcontroller, external sensors, and other components such as EEPROM and LED. WISPs have been used for light level measurement, acceleration sensing, cold chain monitoring (passive data

neg: DVB-T2 planning DVB-T2 equipment launches include Alitronika, CellMetric, Cisco, Digital TV Labs, Humax, NXP Semiconductors, Panasonic, ProTelevision Technologies, Screen Service, SIDSA, Sony, ST Microelectronics and T-VIPS. The first test from a real TV transmitter was performed by the "BBC Research & Innovation" in the last weeks of June 2008 using channel 53 from the Guildford transmitter, southwest of London: BBC had developed and built the modulator/demodulator prototype in parallel with the DVB-T2 standard being drafted. Other companies like ENKOM or IfN develop software (processor) based decoding. NORDIG published a DVB-T2 receiver specification and performance requirement on 1 July 2009. In March

neg: Demodulation both modulate and demodulate a carrier wave with FM, and AM predates it by several decades. There are several common types of FM demodulators: QAM demodulation requires a coherent receiver. Demodulation Demodulation is extracting the original information-bearing signal from a carrier wave. A demodulator is an electronic circuit (or computer program in a software-defined radio) that is used to recover the information content from the modulated carrier wave. There are many types of modulation so there are many types of demodulators. The signal output from a demodulator may represent sound (an analog audio signal), images (an analog video signal) or

neg: Product detector Product detector A product detector is a type of demodulator used for AM and SSB signals. Rather than converting the envelope of the signal into the decoded waveform like an envelope detector, the product detector takes the product of the modulated signal and a local oscillator, hence the name. A product detector is a frequency mixer. Product detectors can be designed to accept either IF or RF frequency inputs. A product detector which accepts an IF signal would be used as a demodulator block in a superheterodyne receiver, and a detector designed for RF can be combined with an RF

neg: Optical DPSK demodulator Optical DPSK demodulator An Optical DPSK demodulator is a device that provides a method for converting an optical differential phase-shift keying (DPSK) signal to an intensity-keyed signal at the receiving end in fiber-optic communication networks. It is also known as delay line interferometer (DLI), or simply called DPSK demodulator. The DPSK decoding method is achieved by comparing the phase of two sequential bits. An incoming DPSK optical signal is first split into two beams with equal intensities, in which one beam is delayed in space by an optical path difference that introduces a time delay corresponding to "one bit". The

neg: Broadcast flag In the United States, new television receivers using the ATSC standard were supposed to incorporate this functionality by July 1, 2005. Officially called "Digital Broadcast Television Redistribution Control," the FCC's rule is in 47 CFR 73.9002(b) and the following sections, stating in part: "No party shall sell or distribute in interstate commerce a Covered Demodulator Product that does not comply with the Demodulator Compliance Requirements and Demodulator Robustness Requirements." According to the rule, hardware must "actively thwart" piracy. The rule's Demodulator Compliance Requirements insists that all HDTV demodulators must "listen" for the flag (or assume it to be present in

neg: Pulse-code modulation amount of high-frequency energy due to aliasing effects. To remove these undesirable frequencies, the demodulator passes the signal through a reconstruction filter that suppress energy outside the expected frequency range (greater than the Nyquist frequency formula_1). Common sample depths for LPCM are 8, 16, 20 or 24 bits per sample. LPCM encodes a single sound channel. Support for multichannel audio depends on file format and relies on synchronization of multiple LPCM streams. While two channels (stereo) is the most common format, systems can support up to 8 audio channels (7.1 surround) or more. Common sampling frequencies are 48 kHz as

neg: Analog television (specifically: bandwidth-limited) way 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: In the end, further matrixing of the above color-difference signals c through f yielded

neg: Optical DPSK demodulator on the type of interferometer used. DQPSK is the four-level version of DPSK. DQPSK transmits two bits for every symbol (bit combinations being 00, 01, 11 and 10) and has an additional advantage over conventional binary DPSK. DQPSK has a narrower optical spectrum, which tolerates more dispersion (both chromatic and polarization-mode), allows for stronger optical filtering, and enables closer channel spacing. As a result, DQPSK allows processing of 40 Gbit/s data-rate in a 50 GHz channel spacing system. A demodulator for optical DQPSK signals can be constructed using two matched DPSK demodulators with phase off-set at formula_1. Optical DPSK demodulator

neg: Ulipristal acetate Ulipristal acetate Ulipristal acetate, sold under the brand name Ella among others, is a medication used for emergency birth control and uterine fibroids. As emergency birth control it should be used within 120 hours of sex. For fibroids it may be taken for up to six months. It is taken by mouth. Common side effects include headache, nausea, feeling tired, and abdominal pain. It should not be used in people who are already pregnant. It is in the selective progesterone receptor modulator (SPRM) class of medications. It works by preventing the effects of progesterone thus stopping ovulation. Ulipristal acetate was

neg: Common Interface are proprietary to individual suppliers. Each one uses their own algorithms and there is no defined standard for them. As the full MPEG-2 transport data stream comes out of the demodulator, and error correction units, the DTV Receiver sends it through the card plugged into the Common Interface, before it is processed by the MPEG demultiplexer in the receiver. If several CI cards are present, the MPEG transport data stream will be passed sequentially through all these cards. An embedded CAM may not physically exist, as it may be in CPU software. In such a case, only the smart card

neg: Alfaxalone Alfaxalone Alfaxalone, also known as alphaxalone or alphaxolone and sold under the brand name Alfaxan, is a neuroactive steroid and general anesthetic which is used in veterinary practice as an induction agent for anesthesia and as an injectable anesthetic. Though it is more expensive than other induction agents, it often preferred due to the lack of depressive effects on the cardiovascular system. The most common side effect is respiratory depression; when premedications aren't given, patients also become agitated and hypersensitive when waking up. Alfaxalone works as a positive allosteric modulator on GABA receptors and, at high concentrations, as a direct

neg: Fingolimod Fingolimod Fingolimod (INN, trade name Gilenya, Novartis) is an immunomodulating drug, mostly used for treating multiple sclerosis (MS). It has reduced the rate of relapses in relapsing-remitting multiple sclerosis by approximately one-half over a two-year period. Fingolimod is a sphingosine-1-phosphate receptor modulator, which sequesters lymphocytes in lymph nodes, preventing them from contributing to an autoimmune reaction. Fingolimod is used in the treatment of the relapsing form of multiple sclerosis. Its effect in those with primary progressive MS is not clear. It may also be used in chronic inflammatory demyelinating polyneuropathy. The most common side effects of fingolimod have been head

neg: Demodulation amplitude, frequency or phase are transmitted in the carrier signal. For example, for a signal modulated with a linear modulation like AM (amplitude modulation), we can use a synchronous detector. On the other hand, for a signal modulated with an angular modulation, we must use an FM (frequency modulation) demodulator or a PM (phase modulation) demodulator. Different kinds of circuits perform these functions. Many techniques such as carrier recovery, clock recovery, bit slip, frame synchronization, rake receiver, pulse compression, Received Signal Strength Indication, error detection and correction, etc., are only performed by demodulators, although any specific demodulator may perform only

neg: Output coupler a light wave to complete one round-trip through the cavity, hence the name. After building in intensity the cavity suddenly "dumps" its energy. Cavity dumpers usually use a high-reflective mirror on each end of the cavity, allowing the beam to receive full gain from the medium. At a specific interval, the beam is redirected, using a device such as a Pockels cell, an acousto-optic modulator, or a fast-rotating prism or mirror. This redirected beam bypasses the end mirror, allowing a very powerful pulse to be emitted. Cavity dumpers can be used for continuous-wave operation, but their most common use is

neg: Selective androgen receptor modulator LGD-4033, a claim that the University of Florida denies. On March 25, 2017 Joakim Noah was banned for twenty games by the NBA for testing positive for Selective Androgen Receptor Modulator LGD-4033. In October 2017, the Food and Drug Administration issued warning letters to three supplement companies notifying them that SARMS are classed as unapproved drugs and can cause potential adverse side effects associated including cardiovascular and liver damage. Selective androgen receptor modulator Selective androgen receptor modulators or SARMs are a novel class of androgen receptor ligands. (The name follows the terminology currently used for similar molecules targeting the estrogen

neg: Analog television performs amplification to the IF stages from the microvolt range to fractions of a volt. At this point the IF signal consists of a video carrier signal at one frequency and the sound carrier at a fixed offset. 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

neg: Photoelastic modulator Photoelastic modulator A photoelastic modulator (PEM) is an optical device used to modulate the polarization of a light source. The photoelastic effect is used to change the birefringence of the optical element in the photoelastic modulator. PEM was first invented by J. Badoz in the 1960s and originally called a "birefringence modulator." It was initially developed for physical measurements including optical rotary dispersion and Faraday rotation, polarimetry of astronomical objects, strain-induced birefringence, and ellipsometry. Later developers of the photoelastic modulator include J.C Kemp, S.N Jasperson and S.E Schnatterly. The basic design of a photoelastic modulator consists of a piezoelectric transducer

neg: Ring modulation are created, with one at "f" + "f" and the other at "f" – "f". The two new waves are unlikely to be harmonically related and (in a well designed ring modulator) the original signals are not present. It is this that gives the ring modulator its unique tones. Intermodulation products can be generated by carefully selecting and changing the frequency of the two input waveforms. If the signals are processed digitally, the frequency-domain convolution becomes circular convolution. If the signals are wideband, this will cause aliasing distortion, so it is common to oversample the operation or low-pass filter the

neg: Ring modulation Ring modulation In electronics, ring modulation is a signal-processing function, an implementation of frequency mixing, performed by multiplying two signals, where one is typically a sine wave or another simple waveform and the other is the signal to be modulated. A ring modulator is an electronic device for ring modulation. A ring modulator may be used in music synthesizers and as an effects unit. The function derives its name from the fact that the analog circuit of diodes originally used to implement this technique takes the shape of a ring. The circuit is similar to a bridge rectifier, except that

neg: Superheterodyne receiver detector using a so-called beat frequency oscillator, and there are other techniques used for different types of modulation. The resulting audio signal (for instance) is then amplified and drives a loudspeaker. When so-called high-side injection has been used, where the local oscillator is at a "higher" frequency than the received signal (as is common), then the frequency spectrum of the original signal will be reversed. This must be taken into account by the demodulator (and in the IF filtering) in the case of certain types of modulation such as single sideband. To overcome obstacles such as image response, in some

neg: Nanoradio different shapes such as bent, straight or toroidal. Common among all nanoradios is how relatively strong they are. The resistance can be attributed to the strength of the bonds between carbon atoms. The fundamental parts of a radio are the antenna, tuner, demodulator and amplifier. Carbon nanotubes are special in that they can function as these parts without the need of extra circuitry. The nanoradio is small enough for electromagnetic signals to mechanically vibrate the nanoradio. The nanoradio essentially acts as an antenna by vibrating with the same frequency as the signal from incoming electromagnetic waves; this is in contrast

neg: Mode-locking light. Passive methods do not use an external signal, but rely on placing some element into the laser cavity which causes self-modulation of the light. The most common active mode-locking technique places a standing wave electro-optic modulator into the laser cavity. When driven with an electrical signal, this produces a sinusoidal amplitude modulation of the light in the cavity. Considering this in the frequency domain, if a mode has optical frequency "ν", and is amplitude-modulated at a frequency "f", the resulting signal has sidebands at optical frequencies and . If the modulator is driven at the same frequency as the

neg: RF modulator RF modulators are used in low-end car audio to add devices like CD changers without requiring dashboard hardware upgrades. For example, a portable CD player's headphone jack is connected to the modulator, which outputs a low-power FM radio signal that is played through the car radio. Car FM modulators suffer from loss of quality and interference issues. Later devices which would use these types of modulators would be iPods and similar portable media players. RF modulator An RF modulator (or radio frequency modulator) is an electronic device whose input is a baseband signal which is used to modulate a radio

neg: Crystal detector a lower forward voltage drop than silicon (0.3 vs 0.7 volts). Today a few galena cat whisker detectors are still being made, but only as antique replicas or devices for science education. Crystal detector A crystal detector is an obsolete electronic component in some early 20th century radio receivers that used a piece of crystalline mineral as a detector (demodulator) to rectify the alternating current radio signal to extract the audio modulation which produced the sound in the earphones. It was the first type of semiconductor diode, and one of the first semiconductor electronic devices. The most common type was

neg: Optical DPSK demodulator two beams in the two paths are then coherently recombined to interfere each other constructively or destructively. The interference intensity is measured and becomes the intensity-keyed signal. A typical optical system for such a purpose is Mach-Zehnder interferometer or Michelson interferometer, forming an optical DPSK Demodulator. Delay time depends on the data rate. For instance, in a 40 Gbit/s system, one bit corresponds to 25 picoseconds, and light travels 5 mm in a fiber optics or 7.5 mm in free space within that period. Thus the optical path difference between the two beams is 5 mm or 7.5 mm depending

neg: Constellation diagram "alphabet" of symbols that can be transmitted by each sample, and so determines the number of bits transmitted per sample. It is usually a power of 2. A diagram with four points, for example, represents a modulation scheme that can separately encode all 4 combinations of two bits: 00, 01, 10, and 11 and so can transmit two bits per sample. Thus in general a modulation with formula_1 constellation points transmits formula_2 bits per sample. After passing through the communication channel the signal is decoded by a demodulator. The function of the demodulator is to classify each sample as a

neg: Satellite modem side. This is achieved by the following two circuits: There are also additional components in the demodulator such as the Intersymbol interference equalizer. If the analog signal was digitized without a four-quadrant multiplier, the complex envelope has to be calculated by a digital "complex mixer". Sometimes a digital automatic gain control circuit is implemented in the demodulator. Error correction techniques are essential for satellite communications, because, due to satellite's limited power a signal to noise ratio at the receiver is usually rather poor. Error correction works by adding an artificial redundancy to a data stream at the transmitting side, and

neg: Amplitude modulation broadcast and amateur radio) also generate AM by controlling the gain of the transmitter's final amplifier (generally class-C, for efficiency). The following types are for vacuum tube transmitters (but similar options are available with transistors): The simplest form of AM demodulator consists of a diode which is configured to act as envelope detector. Another type of demodulator, the product detector, can provide better-quality demodulation with additional circuit complexity. Amplitude modulation Amplitude modulation (AM) is a modulation technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. In amplitude modulation, the amplitude (signal strength) of the

neg: DTV receiver a cable, a satellite, or terrestrial network and isolates a particular channel. The signal is then forwarded to a demodulator and converted to binary format. Once in binary format, the demodulator will check for error and forward the binary signal to a demultiplexer that will extract audio, video, and data from the binary stream. Once the demultiplexer has finished with the signal, the decoders will transform the digital bits into a format suitable for viewing on the television set. As the architecture of a DTV receiver can vary in function of the network operator or the set-box manufacturer, we have

neg: Allosteric modulator modulators are both allosteric agonists and allosteric modulators. An ago-allosteric modulator acts as an agonist and an enhancer for endogenous agonists in increasing agonist potency (the dose range over which a response is produced) and providing "superagonism". Superagonism results when the efficacy is greater than 100 percent. Ago-allosteric modulators can be neutral, negative, or positive. Neutral ago-allosteric modulators increase efficacy, but have no effect on potency. A negative ago-allosteric modulator has a negative effect on the potency but a positive effect on the efficacy of an agonist. A positive ago-allosteric modulator increases both efficacy and potency. Allosteric modulator In biochemistry

neg: Photoelastic modulator (and often detected with a lock-in amplifier), excluding many sources of noise not at the PEM operating frequency and attenuating the white noise by the bandwidth of the lock-in amplifier. Photoelastic modulator A photoelastic modulator (PEM) is an optical device used to modulate the polarization of a light source. The photoelastic effect is used to change the birefringence of the optical element in the photoelastic modulator. PEM was first invented by J. Badoz in the 1960s and originally called a "birefringence modulator." It was initially developed for physical measurements including optical rotary dispersion and Faraday rotation, polarimetry of astronomical objects,

neg: Compatible Discrete 4 or "Micro Ridge" type. By contrast, a standard "conical" or cone shape stylus has less contact area with the record groove. CD-4 playback in 4 channels also requires a specialized CD-4 demodulator. Such demodulators have not been sold commercially since the 1970s. These were often built as independent components. However, some audio receivers and or amplifiers built in the 1970s included the CD-4 demodulator as a built-in feature, along with FM radio and amplifier circuitry. A typical high-performance CD-4 system would include a turntable with a CD-4 compatible phono cartridge, a CD-4 demodulator, a four-channel amplifier (or receiver), and four

neg: Underwater acoustic communication single broadcast waveform can be considered the significant items. 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. Since this scheme depends on the difference between successive phases, it is termed differential phase-shift keying (DPSK). 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). In exchange, it produces more erroneous demodulation. Orthogonal frequency-division

neg: Frequency modulation signals can be generated using either direct or indirect frequency modulation: Many FM detector circuits exist. A common method for recovering the information signal is through a Foster-Seeley discriminator or ratio detector. A phase-locked loop can be used as an FM demodulator. "Slope detection" demodulates an FM signal by using a tuned circuit which has its resonant frequency slightly offset from the carrier. As the frequency rises and falls the tuned circuit provides a changing amplitude of response, converting FM to AM. AM receivers may detect some FM transmissions by this means, although it does not provide an efficient means

neg: Barrie Gilbert Barrie Gilbert Barrie Gilbert (born 1937 in Bournemouth, England) is an English-American inventor. He is well known for his invention of numerous analog circuit concepts, holding over 100 patents worldwide, and for the discovery of the Translinear Principle. His name is attributed to a class of related topologies loosely referred to as the Gilbert cell, one of which is a mixer - a key frequency translation device - used in every modern wireless communication device. A similar topology, for use as a synchronous demodulator, was invented by Howard Jones in 1963. During the 1950s he pursued an interest in solid-state

neg: Overlap zone Overlap zone An overlap zone, in radio frequency engineering, is a zone in which the signals from two or more radio stations, transmitting at the same frequency, can be received with comparable intensity. Interference occurs frequently in such a zone. In order to avoid this, a receiver with directional antenna is used, which can then be aligned in such a way that it will only receive the signal of one transmitter. Alternatively, the signals could be separated using a demodulator in single sideband mode. With digital radio (Digital Radio Mondiale and Digital Audio Broadcasting being two common types), there is

neg: Atari 8-bit family in the television frequency range. A device known as an RF modulator is normally used for television output, and these are difficult to shield to the levels being mandated by the FCC. Other manufacturers had avoided this problem using composite monitors, like the PET or TRS-80. Apple solved the problem by leaving those components out of the Apple II, and instead contracted M&R Enterprises to sell them under the name "Sup'R'Mod". The FCC required the entire device generating the signals to be tested as a whole, but as the RF modulator was sold by a 3rd party it was not

neg: Television transmitter V limit is for luminance signal. Some operators may accept superimposed color signals slightly over 1 V.) After buffer and 1 V clipping circuits, the signal is applied to the modulator where it modulates an intermediate frequency signal (which is different from the one used for aural signal.) The modulator is an amplitude modulator which modulates the IF signal in a manner where 1 V VF corresponds to low level IF and 0 volt VF corresponds to high level IF. AM modulator produces two symmetrical side bands in the modulated signals. Thus, IF band width is two times the video

neg: Coding theory the demodulator only as a low-level noise. Another general class of codes are the automatic repeat-request (ARQ) codes. In these codes the sender adds redundancy to each message for error checking, usually by adding check bits. If the check bits are not consistent with the rest of the message when it arrives, the receiver will ask the sender to retransmit the message. All but the simplest wide area network protocols use ARQ. Common protocols include SDLC (IBM), TCP (Internet), X.25 (International) and many others. There is an extensive field of research on this topic because of the problem of matching

neg: Modulating retro-reflector modulation rate can be faster. However, for longer application ranges on the order of several hundred meters, larger apertures are needed to close the link. For a given modulator, the speed of the shutter scales inversely as the square of the modulator diameter. When the drive voltage waveform is optimized, the electrical power consumption of a MQW modulating retro-reflector varies as: Where D is the diameter of the modulator, V is the voltage applied to the modulator (fixed by the required optical contrast ratio), B is the maximum data rate of the device, and R is the sheet resistance of

neg: SAM Coupé array of expansion ports were provided, including: Uniquely the SAM's RF modulator was built into the power supply unit and connected via a joint power/TV socket. This made signal interference from the ACDC converter common and it was a popular but entirely unofficial modification to remove the modulator and keep it as a separate unit. Due to a flaw in the design, when two joysticks were used at the same time (through the approved splitter) they would interfere with each other. Up to four devices could be connected to the Coupé's Euroconnector port, through the use of the SAMBUS, which

neg: Product detector envelope detector is a simple and relatively inexpensive circuit, and it can provide higher fidelity, since there is no possibility of mistuning the local oscillator. A product detector (or equivalent) is needed to demodulate SSB signals. Product detector A product detector is a type of demodulator used for AM and SSB signals. Rather than converting the envelope of the signal into the decoded waveform like an envelope detector, the product detector takes the product of the modulated signal and a local oscillator, hence the name. A product detector is a frequency mixer. Product detectors can be designed to accept either

neg: AN/ARC-164 selected, an ECCM slice capable of storing multiple Word-of-Day patterns for Havequick operation, and can also serve as a channel selector and audio demodulator for separate UHF DF systems. There are 2 common installations: remote and panel. With a remote installation, the R/T is in a remote location, while the panel installation features an all-in-one R/T and control panel. AN/ARC-164 The AN/ARC-164 is a aircraft station (also: "aircraft radio station") that operates in the aeronautical mobile (OR) service / B band (NATO). It might be found on B-52G/H, B-1B, C/EC/RC-26D, KC-135, C-23, C-130, C-141, F-15, A-10, F-16, UH-1D, CH-47, H-53,

neg: Radio receiver three functions above are performed consecutively: (1) the mix of radio signals from the antenna is filtered to extract the signal of the desired transmitter; (2) this oscillating voltage is sent through a radio frequency (RF) amplifier to increase its strength to a level sufficient to drive the demodulator; (3) the demodulator recovers the modulation signal (which in broadcast receivers is an audio signal, a voltage oscillating at an audio frequency rate representing the sound waves) from the modulated radio carrier wave; (4) the modulation signal is amplified further in an audio amplifier, then is applied to a loudspeaker or

neg: Federal Signal Modulator of Modulators. They use just over 20 5020's and 5020B's, and use them primarily for chemical releases. The Modulators in Olmsted County, Minnesota are famous for their pre-test and post-test voice announcements, and also for only being located in parks. The Modulators in Monroe County, Michigan are extremely well known for their quite irritating pre-test voice announcements. There is a unique "rainbow" Modulator located in Monroe County as well. Eden Prairie, Minnesota has a uniquely mouted Modulator 5020 on top of a parking garage which has a custom attack tone that cannot be found on other Modulators. Strangely, this Modulator

neg: GTx Incorporated GTx Incorporated GTx, Inc is a pharmaceutical company that is working on drugs in the selective estrogen receptor modulator (SERM) and selective androgen receptor modulator (SARM) classes. Its drugs in development include enobosarm (ostarine) and GTx-758. The company was founded in Memphis in 1997 by Mitch Steiner and Marc S. Hanover. The company was originally called Genotherapeutics, changed its name to GTx, Inc. in 2001, and reincorporated in Delaware in 2003. The company licensed toremifene from Orion Corporation, and licensed andarine, enobosarm and prostarine from the University of Tennessee Research Foundation; the SARM compounds from Tennessee had been invented by

neg: Spatial light modulator In this case spiral beam parameters can be changed dynamically. As its name implies, the image on an electrically addressed spatial light modulator is created and changed electronically, as in most electronic displays. EASLMs usually receive input via a conventional interface such as VGA or DVI input. They are available at resolutions up to QXGA (2048 × 1536). Unlike ordinary displays, they are usually much smaller (having an active area of about 2 cm²) as they are not normally meant to be viewed directly. An example of an EASLM is the Digital Micromirror Device at the heart of DLP displays

neg: Crystal detector Crystal detector A crystal detector is an obsolete electronic component in some early 20th century radio receivers that used a piece of crystalline mineral as a detector (demodulator) to rectify the alternating current radio signal to extract the audio modulation which produced the sound in the earphones. It was the first type of semiconductor diode, and one of the first semiconductor electronic devices. The most common type was the so-called cat whisker detector, which consisted of a piece of crystalline mineral, usually galena (lead sulfide), with a fine wire touching its surface. The "asymmetric conduction" of electric current across electrical

neg: Armstrong phase modulator into the sidebands, the carrier power is reduced. A balanced modulator mixes the audio signal and the radio frequency carrier, but suppresses the carrier, leaving only the sidebands. The output from the balanced modulator is a double sideband suppressed carrier signal and it contains all the information that the AM signal has, but without the carrier. It is possible to generate an AM signal by taking the output from the balanced modulator and reinserting the carrier. In the Armstrong method, the audio signal and the radio frequency carrier signal are applied to the balanced modulator to generate a double sideband

neg: Piezoresponse force microscopy of easy steps. The reference signal formula_5, and input signal, formula_6, are multiplied together to give the "demodulator output", formula_7 where "A" is the input signal Amplitude and "B" is the reference signal Amplitude, "ω" is the frequency of both the reference and input signals, and "φ" is any phase shift between the two signals. The above equation has an AC component at twice the frequency of the original signals (second term) and a DC component (first term) whose value is related to both the amplitude and phase of the input signal. The demodulator output is sent through a low-pass

neg: Piezoresponse force microscopy filter to remove the 2"ω" component and leave the DC component then the signal is integrated over a period of time defined as the "Time Constant", "τ" which is a user-definable parameter. Several different outputs are commonly available from a LiA: "X" output is the demodulator output and "Y" is the second demodulator output which is shifted by 90° in reference to the first output, together they hold both the phase, "θ", and magnitude, "R", information and are given by formula_8 and formula_9 However, phase and amplitude of the input signal can also be calculated and made output from the

neg: Fiber laser electro-optic modulator, Mach-Zehnder integrated-optic modulators, or a semiconductor electro-absorption modulator (EAM). The principle of active mode-locking with a sinusoidal modulation. In this situation, optical pulses will form in such a way as to minimize the loss from the modulator. The peak of the pulse would automatically adjust in phase to be at the point of minimum loss from the modulator. Because of the slow variation of sinusoidal modulation, it is not very straightforward for generating ultrashort optical pulses (< 1ps) using this method. For stable operation, the cavity length must precisely match the period of the modulation signal or some

neg: Constellation diagram symbol. The set of sample values which the demodulator classifies as a given symbol can be represented by a region in the plane drawn around each constellation point. If noise causes the point representing a sample to stray into the region representing another symbol, the demodulator will misidentify that sample as the other symbol, resulting in a symbol error. Most demodulators choose, as its estimate of what was actually transmitted, the constellation point which is closest (in a Euclidean distance sense) to that of the received sample; this is called maximum likelihood detection. On the constellation diagram these detection regions

neg: Selective androgen receptor modulator Selective androgen receptor modulator Selective androgen receptor modulators or SARMs are a novel class of androgen receptor ligands. (The name follows the terminology currently used for similar molecules targeting the estrogen receptor, "selective estrogen receptor modulators," such as tamoxifen.) They are intended to have the same kind of effects as androgenic drugs but be much more selective in their action, allowing them to be used for more uses than the relatively limited legitimate uses of anabolic steroids. Currently used androgens for male hormone replacement therapy are typically injectable or skin delivery formulations of testosterone or testosterone esters. Injectable forms of

neg: Pop (U.S. TV network) for the satellite feed's video and a Zephyrus Electronics Ltd model 100 rev. C demodulator/switching ISA card for manipulating the feed's audio. Also included were a Zephyrus Electronics Ltd. model 101 rev. C demodulator ISA card for the WGN data stream, and a Great Valley Products Zorro II A2000 HC+8 Series II card (used only for 2 MB of Fast RAM with SCSI disabled). The 101C fed demodulated listings data at 2400 baud from a DE9 RS232 serial connector on its backpanel to the Amiga's stock DB25 RS232 serial port via a short cable. The 101C also featured connection terminals

neg: Optical modulator modulator can be manipulated by the Franz-Keldysh effect, the Quantum-confined Stark effect, excitonic absorption, changes of Fermi level, or changes of free carrier concentration. Usually, if several such effects appear together, the modulator is called an electro-absorptive modulator. Refractive modulators most often make use of an electro-optic effect. Some modulators utilize an acousto-optic effect or magneto-optic effect or take advantage of polarization changes in liquid crystals. The refractive modulators are named by the respective effect: i.e. electrooptic modulators, acousto-optic modulators etc. The effect of a refractive modulator of any of the types mentioned above is to change the phase of

neg: RF modulator the demodulation in the television. RF modulators are commonly integrated into VCRs, in video game consoles up to and including the fourth generation, and in 8- and 16-bit home computers. Some systems were supplied with an external modulator unit that connected to both the system and to the antenna jacks of a television. One reason for this is that a device which outputs an RF signal must in general be certified by regulatory authorities—such as the U.S. Federal Communications Commission (FCC) — and thus by having an external RF modulator, only the modulator itself needed to be certified, rather than

neg: Olivia MFSK 256 samples in time and the window that shapes them is 512 samples long. The demodulator is based on the FFT with the size of 512 points. The tone spacing in frequency is 8000 Hz/256 = 31.25 Hz and the demodulator FFT has the resolution of 8000 Hz/512 = 15.625 Hz thus half of the tone separation. To adapt the system to different propagation conditions, the number of tones and the bandwidth can be changed and the time and frequency parameters are proportionally scaled. The number of tones can be 2, 4, 8, 16, 32, 64, 128 or 256. The

neg: Federal Signal Modulator Federal Signal Modulator Federal Signal Modulators (also known as Modulator Speaker Arrays) are electronic warning devices produced by Federal Signal Corporation that are used to alert the public about tornadoes, severe weather, earthquakes, fires, lahars or any other disaster. They are identified mostly by their distinctive stacked "flying saucer" design. The Modulator II is more sold on the side of the siren. The Modulator is composed of speaker cells (ranging from two to eight with the exception of seven) that contain four speaker drivers per cell, although two models (model 6032 and 6048) had additional drivers available when they were

neg: LaserDisc and DTS audio, is aware of AC-3 audio tracks, and has an AC-3 coaxial output; an external or internal AC-3 RF demodulator and AC-3 decoder; and a DTS decoder. Many 1990s A/V receivers combined the AC-3 decoder and DTS decoder logic, but an integrated AC-3 demodulator is rare both in LaserDisc players and in later A/V receivers. PAL LaserDiscs have a slightly longer playing time than NTSC discs, but have fewer audio options. PAL discs only have two audio tracks, consisting of either two analog-only tracks on older PAL LDs, or two digital-only tracks on newer discs. In comparison, later

neg: GABAA receptor negative allosteric modulator terbequinil, tetramethylenedisulfotetramine (TETS), and ZK-93426 as well as the endogenous neurosteroids dehydroepiandrosterone sulfate (DHEA-S), pregnenolone sulfate, epipregnanolone, and isopregnanolone. Some naturally occurring GABA receptor NAMs like cicutoxin and picrotoxin are considered to be toxins, while other GABA receptor NAMs like dieldrin, fipronil, and TETS are used as pesticides (e.g., insecticides, rodenticides), and yet other GABA receptor NAMs like bemegride, flurothyl, and pentylenetetrazol are used for clinical purposes. GABAA receptor negative allosteric modulator A GABA receptor negative allosteric modulator is a negative allosteric modulator (NAM), or inhibitor, of the GABA receptor, a ligand-gated ion channel of the major inhibitory neurotransmitter γ-aminobutyric

neg: Pulse-code modulation analog signal from the discrete data are similar to those used for generating the digital signal. These devices are digital-to-analog converters (DACs). They produce a voltage or current (depending on type) that represents the value presented on their digital inputs. This output would then generally be filtered and amplified for use. To recover the original signal from the sampled data, a "demodulator" can apply the procedure of modulation in reverse. After each sampling period, the demodulator reads the next value and transitions the output signal to the new value. As a result of these transitions, the signal gains a significant

neg: RF modulator RF modulator An RF modulator (or radio frequency modulator) is an electronic device whose input is a baseband signal which is used to modulate a radio frequency source. RF modulators are used to convert signals from devices such as media players, VCRs and game consoles to a format that can be handled by a device designed to receive a modulated RF input, such as a radio or television receiver. Prior to the introduction of specialised video connector standards such as SCART, TVs were designed to only accept signals through the aerial connector: signals originate at a TV station, are transmitted

neg: Federal Signal Modulator still available. Modulators have an inactive (dummy) speaker cell on the bottom of the stack that is used to help project sound in all directions. Without the inactive cell, because of the design of active cells, there would be unbalanced sound distribution. Modulators that are being made now use the UltraVoice (UV) controller. When they were first made, the used with MCP (Modulator Control Plus) and MC (Modulator Controls). Modulator model numbers identify the number of cells, as well as the number of drivers. The family of Modulator array are made up of eight different models, as follows: 1004, 2008,