Search Results - Modulator
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In telecommunications, modulation is the process of varying a periodic waveform, i.e. a tone, in order to use that signal to convey a message, in a similar fashion as a musician may modulate the tone from a musical instrument by varying its volume, timing and pitch. Normally a high-frequency sinusoid waveform is used as carrier signal. The three key parameters of a sine wave are its amplitude ("volume"), its phase ("timing") and its frequency ("pitch"), all of which can be modified in accordance with a low frequency information signal to obtain the modulated signal. A device that performs modulation is known as a modulator and a device that performs the inverse operation of modulation is known as a demodulator (sometimes detector or demod). A device that can do both operations is a modem (short for "Modulate-Demodulate"). The aim of digital modulation is to transfer a digital bit stream over an analog bandpass channel, for example over the public switched telephone network (where a filter limits the frequency range to between 300 and 3400 Hz) or a limited radio frequency band. The aim of analog modulation is to transfer an analog lowpass signal, for example an audio signal or TV signal, over an analog bandpass channel, for example a limited radio frequency band or a cable TV network channel.
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Showing 1 to 11 of 11 Articles matching 'Modulator' in related articles. |
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1. How to Improve Web Templates
June 23, 2008
The web is a complete group on interconnected computers discussion to one another. The computers are usually connected by land lines, modulator satellite signals, cables, and other types of data-transfer mechanisms. A 'data-transfer mechanism' is a way to move data from point A to point B to point C and so on. The computers that compose up the web can be connected all the time or they can be connected only occasionally. The computers that are connected all the time are characteristically called a server. Server software is formed to 'serve' web pages and web sites. Basically, the server comput... (read more)
Author: Priya Singh
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2. Modem Basics
April 27, 2008
The word modem is made up from two other words, modulator and demodulator. You need a modem to enable your computer to transmit over telephone lines. The modem converts the digital data in the computer into analogue form that the telephone wire can accept, and back again. A modem can be external - that is, it can be attached to the outside of any computer with an RS-232 port. Most personal computers have such a port. The modem can also be internal, fitting into an expansion slot as an expansion board The speed of a fast modem is referred to as bits per second or bps. Really fast mo... (read more)
Author: Melanie C
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3. Miss conceptions about the 4L60E 4L80E
April 20, 2008
1-What controls the shifts in a 4L60E 4L80E and can I replace the PCM with a vacuum modulator.
The answer is the PCM is in complete control of every aspect of when and how the 4L60E shifts, Line Pressure and Lockup. If the command is given barring any mechanical failure clutches, Band ETC the transmission must make the shift or slip and burn itself up trying. Alternately It cannot shift before its commanded. Lockup again is strictly a function of the PCM turning on the lockup solenoid and pulsing the PWM solenoid. I hear a lot of people say my converter locks up sometimes and other not ... (read more)
Author: David Watson
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4. Brahmi to avoid Mood Fluctuation and Benefits
April 16, 2008
Brahmi is an herb that is known to man kind as a brain enhancer. It is also an herb that has been used as a brain modulator.
Brahmi is used to revitalize the body and as a memory support. It helps to overcome the negative effects of stress. It is exclusive in its ability to revitalize mental processes whilst reducing the effects of anxiety.
Mood fluctuation though is a disorder that is related to the brain but still it is highly influenced by the disturbances of the normal metabolic disorders in the body. Due to metabolic disturbances, our body remains under nourished and hence the p... (read more)
Author: Peter rodrick
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5. Faces of DARPP-32: Master Signaling Mediator in the Brain?
December 06, 2007
As a major target for dopamine-activated adenylyl cyclase and protein kinase A in the striatum, DARPP-32 plays a central role in regulating the efficacy of dopaminergic neurotransmission and can act either as a phosphatase or kinase inhibitor in a contextually dependent manner. Growing evidence points to DARPP-32 as a key mediator/modulator in numerous signal transduction cascades implicated in a growing number of neurological disorders such as schizophrenia and depression, as well as in drug abuse and addiction. For example, it has been shown that acute exposure of mice to cocaine increases ... (read more)
Author: Stephen Jones
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6. Satellite Modem Working
November 03, 2007
Satellite Modem Working
A satellite modem or satmodem is a modem used to establish data transfers using a communications satellite as a relay. A "modem" stands for "modulator-demodulator". 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 doesn't comprise any modulator) that are also referred to as "satellite modems". These devices are used in satellite Internet access (in this case data are transferred in other direction through a conventional PSTN modem or an ADSL modem... (read more)
Author: Surendra Dayama
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7. Enjoy Wireless Connectivity to the Internet with 3G Modem
June 20, 2007
Modem, a term derived form Modulator-Demodulator used to stand for a device that allowed a computer or terminal to transmit data over a standard dial-up telephone. This description of a modem is inadequate and was suitable only until the late 1990s. Since the advent of high-speed cable and DSL connections, modem now refers to devices that offer low-speed dial-up or high-speed broadband. Taking technology one step ahead, the wireless 3G modem provides global wireless access to the Internet and e-mail.
USB wireless 3G modem creates connection of computers and private networks with the In... (read more)
Author: Darlene Kaitlene
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8. Nolvadex (Tamoxifen Citrate) Profiles by MedPharmaCare
April 03, 2007
Active Life: 5-7 days Drug Class: Selective Estrogen Receptor Modulator (Oral) Average Dose: 10-30 mg/day Acne: Yes Water Retention: No High Blood Pressure: Rare Liver Toxic: low
This remedy is somewhat different from others since it is not an anabolic/androgenic steroid. For male and female bodybuilders, how-ever, it is a very useful and recommended compound which is con-firmed by its widespread use and mostly positive results. Nolvadex belongs to the group of sex hormones and is a so-called antiestrogen. The normal application of Nolvadex is in the treatment of certain forms of br... (read more)
Author: mark henry
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9. Clomid (Clomiphene Citrate) Profiles by MedPharmaCare
March 19, 2007
Active Life: 5-7 days Drug Class: Selective Estrogen Receptor Modulator (Oral) Average Dose: Men 50-100 mg/day Acne: Yes Water Retention: No High Blood Pressure: Rare Liver Toxic: Low Aromatization: None Decrease HPTA function: No, used to restore it Strong gonadotropin stimulator/mild anti-estrogen
Clomid is not an anabolic/androgenic steroid. Since it is a synthetic estrogen it belongs, however, to the group of sex hormones. In school medicine Clomid is normally used to trigger ovulation. Clomid also has a strong influence on the hypothalamohypophysial testicular axis. It stimu... (read more)
Author: mark henry
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10. Buying a Car Radio
August 17, 2006
This guide will help you choose the right radio, CD, MP3 Player or CD Changer for you and your car.
Considerations when replacing your car radio? If you are thinking of replacing or upgrading your original factory fitted car radio but are unsure of the options, benefits and technical considerations then read on, all will be explained. Factory fitted radios (standard fit radios) in the past had relatively low power outputs of about 3 to 5 watts RMS. However the latest factory fitted radios have improved vastly with power outputs of up to 100 Watts. These figures represent 25 Watts, ‘peak... (read more)
Author: Ian I
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11. Reflex regeneration in the bowel
May 06, 2006
The digestive tract is a highly complex organ system. Its functions are mediated through many channels of communication – hormonal, enzymatic, and of course neurological. The bowel is a reflex organ, which is further influenced by both the subconscious and conscious brain. Our autonomic nervous system is the key modulator of digestive system function, but it is of course influenced in turn by many internal and external factors. The sympathetic nervous system has a tendency to reduce bowel function when it is activated, where the parasympathetic tends to promote digestive function. This ... (read more)
Author: Justin Crawford
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