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BY AUQIB KHAN
Wiki User
∙ 11y ago
Wiki User
∙ 14y agoI know you'll find this hard to believe, but it's true: The signal that comes from the satellite all the way down to the little dish on the roof of your garage is on a frequency that has no trouble making the 25,000-mile trip from space to you, but it can't survive the trip through 50 feet of cable from the little dish to your TV inside. The LNB is a "Low-Noise Block" down-converter. It takes all the signals in a wide band of frequencies straight off the dish, and converts them all down to a much lower band of frequencies that can pass through the cable without too much loss, directly into your satellite receiver.
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What is the receiving and transmitting device called that is inside a communication or broadcast satellite that relays received signals back to Earth?
downlink
What electronic device that detects both vertically and horizontally polarized signal simultaneously?
Orthomode transducerFrom Wikipedia, the free encyclopediaOrthomode transducer, VSAT KubandOutdoor unit, includes feed horn, OMT, LNB and BUCOrthomode transducer (Portenseigne, France)Orthomode transducer, vertical and horizontal polarityAntenna side of OMTAn orthomode transducer is a microwave duct component of the class of microwave circulators. It is commonly referred to as an OMT, and commonly referred as a polarisation duplexer. Such device may be part of a VSAT antenna feed Orthomode transducers serve either to combine or to separate two microwave signal paths. One of the paths forms the uplink, which is transmitted over the same waveguide as the received signal path, or downlink path. For VSAT modems the transmission and reception paths are at 90° to each other, or in other words, the signals are orthogonally polarised with respect to each other. This orthogonal shift between the two signal paths provides approximately an isolation of 40dB in the Ku band and Ka band radio frequency bands.Hence this device serves in an essential role as the junction element of the outdoor, unit (ODU) of a VSAT modem. It protects the receiver front-end element (thelow-noise block converter, LNB) from burn-out by the power of the output signal generated by the block up converter (BUC). The BUC is also connected to thefeed horn through a wave guide port of the OMT junction device.Orthomode transducers are used in dual-polarised Very small aperture terminals (VSATs), in sparsely populated areas, radar antennas, radiometers, and communications links. They are usually connected to the antenna's down converter or LNB and to the High Power Amplifier (HPA) attached to a transmittingantenna.Wherever there are two polarisations of radio signals (Horizontal and Vertical), the transmitted and received radio signal to and fro the antenna are said to be "orthogonal". This means that the modulation planes of the two radio signal waves are at 90 degrees angles to each other. The OMT device is used to separate two equal frequency signals, of high and low signal power. Protective separation is essential as the transmitter unit would seriously damage the very sensitive low (µV) micro-voltage, front-end receiver amplifier unit at the antenna.The transmission signal of the up-link, of relatively high power (1, 2,or 5 watts for common VSAT equipment) originating from BUC,(block up converter) and the very low power received signal power (µ-volts) coming from the antenna (aerial) to the LNB receiver unit, in this case are at an angle of 90° relative to each other, are both coupled together at the feed-horn focal-point of the Parabolic antenna. The device that unites both up-link and down-link paths, which are at 90° to each other, is known as an Orthogonal Mode Transducer OMT.In the VSAT Ku band of operation case, a typical OMTOrthomode Transducer provides a 40dB isolation between each of the connected radio ports to the feed horn that faces the parabolic dish reflector (40dB means that only 0.01% of the transmitter's output power is cross-fed into the receiver's wave guide port). The port facing the parabolic reflector of the antenna is a circular polarizing port so that horizontal and vertical polarity coupling of inbound and outbound radio signal is easily achieved.The 40dB isolation provides essential protection to the very sensitive receiver amplifier against burn out from the relatively high-power signal of the transmitter unit. Further isolation may be obtained by means of selective radio frequency filtering to achieve an isolation of 100dB (100dB means that only a 10−10 fraction of the transmitter's output power is cross-fed into the wave guide port of the receiver).The second image demonstrates two types of outdoor units, a 1-watt Hughes unit and a composite configuration of a 2-watt BUC/OMT/LNB Andrew, Swedish Microwave units.The following images show a Portenseigne & HirschmannKu band configuration, that highlights the horizontal the vertical, and circular polarized wave-guide ports that join to the Feed-horn, the LNB or BUC elements of an outdoor unit
Which is HD ready lnb?
There's no such thing as an HD Ready LNB. Any LNB will be fine.
What is the difference between a Quad LNB and a Quatro LNB?
The difference between a Quad LNB and a Quatro LNB is that the Quad LNB is generally used for four receivers or two twin tuner receivers. A switcher is used with a Quatro LNB, and the switcher distributes to however many receivers is needed.
What is difference between quad lnb and quattro lnb?
Quad LNB is used for 4x receivers or 2x twin tuner receivers where a quattro LNB is used with a switcher and can distribute to as many receivers as needed (usually a communual, commercial or large domestic installation. The 2 LNB's use signals differently, so for most domestic installations a quad would be used.
How long are parachute cables?
lnb
Where can someone purchase a LNB satellite?
LNB satellite dishes are used for telecommunications. The LNB stands for low noise block and it is the part of the dish that collects the lowest frequencies. Your satellite TV distributor should be able to help you get hold of one.
What is the power source of LNB?
The LNB gets its power (DC Volts) from the receiver inside the house. This is sent up the same coaxial cable that carries the received signals down to the receiver. A change the voltage is used to change LNB polarity from Vertical to Horizontal.
What is the full name for lnb?
l n b
What is the function of an LNB for satellite television?
LNB stands for Low Noise Block. This device amplifies the weak incoming signal from the satellite and converts it to a signal that is usable by the television.
Is it possible to receive 2 channels with one cable?
hi,guys,if you want to receive 2 Channels with only one Cable on my regular DVB-S Tuner Box.Single can not do this.You should use dual tuner,it has two LNB Control,like LNB A use horizontal, and LNB B use vertical.TBS6981 can do what you want.
Why do LNB's have to be mounted close to the satellite dish?
The LNB takes the signal reflected off the dish, sends that signal through the coax cable to the receiver, where the receiver decodes the signal unlocking the channels you subscribe to.
What is the best type of cable for LNB to satellite receiver?
RG-6 cable.
What is the maximum length for satellite cable lnb to receiver?
Approximately 100 feet.
