REPEATER
When an information-bearing signal passes through a communication channel, it is progressively degraded due to loss of power. For
example, when a telephone call passes through a wire telephone line,
some of the power in the electric current which represents the audio
signal is dissipated as heat in the resistance of the copper wire. The longer the wire is, the more power is lost, and the smaller the amplitude of the signal at the far end. So with a long enough wire the call will not be audible at the other end. Similarly, the farther from a radio station a receiver is, the weaker the radio signal, and the poorer the reception. A
repeater is an electronic device in a communication channel that
increases the power of a signal and retransmits it, allowing it to
travel further. Since it amplifies the signal, it requires a source of electric power.
This is used to increase the range of telephone signals in a telephone line. They are most frequently used in trunklines that carry long distance calls. In an analog telephone line consisting of a pair of wires, it consists of an amplifier circuit made of transistors which use power from a DC current source to increase the power of the alternating current audio signal on the line. Since the telephone is a duplex (bidirectional) communication system, the wire pair carries two audio signals, one going in each direction. So telephone repeaters have to be bilateral, amplifying the signal in both directions without causing feedback, which complicates their design considerably. Telephone repeaters were the first type of repeater and were some of the first applications of amplification. The development of telephone repeaters between 1900 and 1915 made long distance phone service possible. However most telecommunications cables are now fiber optic cables which use optical repeaters (below).
This is used to increase the range of signals in a fiber optic cable. Digital information travels through a fiber optic cable in the form of short pulses of light. The light is made up of particles called photons, which can be absorbed or scattered in the fiber. An optical communications repeater usually consists of a phototransistor which converts the light pulses to an electrical signal, an amplifier to increase the power of the signal, an electronic filter which reshapes the pulses, and a laser which converts the electrical signal to light again and sends it out the other fiber. However, optical amplifiers are being developed for repeaters to amplify the light itself without the need of converting it to an electric signal first. Some repeaters have been powered by light energy transmitted down the fiber with the signal.
This is used to extend the range of coverage of a radio signal. A radio repeater usually consists of a radio receiver connected to a radio transmitter. The received signal is amplified and retransmitted, often on another frequency, to provide coverage beyond the obstruction. Usage of a duplexer can allow the repeater to use one antenna for both receive and transmit at the same time.
This type is used in channels that transmit data in the form of an analog signal in which the voltage or current is proportional to the amplitude of the signal, as in an audio signal. They are also used in trunklines that transmit multiple signals using frequency division multiplexing (FDM). Analog repeaters are composed of a linear amplifier, and may include electronic filters to compensate for frequency and phase distortion in the line.
The digipeater is used in channels that transmit data by binary digital signals, in which the data is in the form of pulses with only two possible values, representing the binary digits 1 and 0. A digital repeater amplifies the signal, and it also may retime, resynchronize, and reshape the pulses. A repeater that performs the retiming or resynchronizing functions may be called a regenerator.
Avery Paul, a disgraced boxer and ex-convict, is hired to abduct a runaway from a notorious drug house and return her safely to her family. But nothing goes as planned and nothing is what it seems.
When I was looking at the cast I thought, oh no not another teenager flick like Twilight or that kind of trash. I have nothing against teenager flicks, I liked Red Riding Hood and Jennifer's Body, but I have something against flicks that are about nothing just some love story. But when I saw Michael (Richard De Klerk) I remembered him from the 4400 series, and the face of Amanda Crew did ring a bell too, Final Destination 3. Dustin Milligan, the third main lead I knew from The Messengers so I knew they could deliver their stuff. And they did, the performances are excellent and you really believe the characters. Somehow the story reminded me of Triangle. You better have full attention to understand it all. It's an excellent flick not only for teens but also for Sci-Fi freaks and for people who can dig thrillers. I won't go that far to say it's a drama because the Sci-Fy takes the main part. It's never explained what has happened to them but the story is strong enough to let you forget that. Their is some red stuff in it, not that it's creepy or anything but it can offend the people with weak stomachs. So it's a bit for everybody, or did I repeat myself?.
1 2 3 4 5 6 7 8 9 10 5.5/10 X Three college friends hit the biggest party of the year, where a mysterious phenomenon disrupts the night, quickly descending into a chaos that challenges their friendships -- and whether they can stay alive.
1 2 3 4 5 6 7 8 9 10 5.5/10 X Avery Paul, a disgraced boxer and ex-convict, is hired to abduct a runaway from a notorious drug house and return her safely to her family. But nothing goes as planned and nothing is what it seems.
This is used to increase the range of telephone signals in a telephone line. They are most frequently used in trunklines that carry long distance calls. In an analog telephone line consisting of a pair of wires, it consists of an amplifier circuit made of transistors which use power from a DC current source to increase the power of the alternating current audio signal on the line. Since the telephone is a duplex (bidirectional) communication system, the wire pair carries two audio signals, one going in each direction. So telephone repeaters have to be bilateral, amplifying the signal in both directions without causing feedback, which complicates their design considerably. Telephone repeaters were the first type of repeater and were some of the first applications of amplification. The development of telephone repeaters between 1900 and 1915 made long distance phone service possible. However most telecommunications cables are now fiber optic cables which use optical repeaters (below).
This is used to increase the range of signals in a fiber optic cable. Digital information travels through a fiber optic cable in the form of short pulses of light. The light is made up of particles called photons, which can be absorbed or scattered in the fiber. An optical communications repeater usually consists of a phototransistor which converts the light pulses to an electrical signal, an amplifier to increase the power of the signal, an electronic filter which reshapes the pulses, and a laser which converts the electrical signal to light again and sends it out the other fiber. However, optical amplifiers are being developed for repeaters to amplify the light itself without the need of converting it to an electric signal first. Some repeaters have been powered by light energy transmitted down the fiber with the signal.
This is used to extend the range of coverage of a radio signal. A radio repeater usually consists of a radio receiver connected to a radio transmitter. The received signal is amplified and retransmitted, often on another frequency, to provide coverage beyond the obstruction. Usage of a duplexer can allow the repeater to use one antenna for both receive and transmit at the same time.
This type is used in channels that transmit data in the form of an analog signal in which the voltage or current is proportional to the amplitude of the signal, as in an audio signal. They are also used in trunklines that transmit multiple signals using frequency division multiplexing (FDM). Analog repeaters are composed of a linear amplifier, and may include electronic filters to compensate for frequency and phase distortion in the line.
The digipeater is used in channels that transmit data by binary digital signals, in which the data is in the form of pulses with only two possible values, representing the binary digits 1 and 0. A digital repeater amplifies the signal, and it also may retime, resynchronize, and reshape the pulses. A repeater that performs the retiming or resynchronizing functions may be called a regenerator.
Avery Paul, a disgraced boxer and ex-convict, is hired to abduct a runaway from a notorious drug house and return her safely to her family. But nothing goes as planned and nothing is what it seems.
When I was looking at the cast I thought, oh no not another teenager flick like Twilight or that kind of trash. I have nothing against teenager flicks, I liked Red Riding Hood and Jennifer's Body, but I have something against flicks that are about nothing just some love story. But when I saw Michael (Richard De Klerk) I remembered him from the 4400 series, and the face of Amanda Crew did ring a bell too, Final Destination 3. Dustin Milligan, the third main lead I knew from The Messengers so I knew they could deliver their stuff. And they did, the performances are excellent and you really believe the characters. Somehow the story reminded me of Triangle. You better have full attention to understand it all. It's an excellent flick not only for teens but also for Sci-Fi freaks and for people who can dig thrillers. I won't go that far to say it's a drama because the Sci-Fy takes the main part. It's never explained what has happened to them but the story is strong enough to let you forget that. Their is some red stuff in it, not that it's creepy or anything but it can offend the people with weak stomachs. So it's a bit for everybody, or did I repeat myself?.
1 2 3 4 5 6 7 8 9 10 5.5/10 X Three college friends hit the biggest party of the year, where a mysterious phenomenon disrupts the night, quickly descending into a chaos that challenges their friendships -- and whether they can stay alive.
1 2 3 4 5 6 7 8 9 10 5.5/10 X Avery Paul, a disgraced boxer and ex-convict, is hired to abduct a runaway from a notorious drug house and return her safely to her family. But nothing goes as planned and nothing is what it seems.
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