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Convert C Ku Band Signal
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Kerrie Gingrich
Dec 5, 2023, 7:12:58 PM12/5/23
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The mixer frequencies that are used to get from one band to another are as follows. To get from Ku-Band to the L-Band you would use 10750 MHz as a Local Oscillator mixer frequency, and to get from C-Band down to L-Band you would use 5150 MHz as a Local Oscillator mixer to down convert to L-Band. The lower product of the mixer is always used to avoid the harmonics of the signal and to keep it from interfering with the converted signal.
The SLM-771 is an L-Band Satellite Level Monitor designed to detect measure and report the receiving level of any RF signal from 5MHz up to 2.5GHz. Use it for early warning of satellite dish and LNB signal degradation due to snow loading, bug & bird intrusions, dish misalignment due to wind or movement, and any increase in LNB loss for whatever reason. It will alert you to the signal reduction before a system failure occurs.
Convert C Ku Band Signal
Download Zip https://shurll.com/2wIzXd
A low-noise block downconverter (LNB) is the receiving device mounted on satellite dishes used for satellite TV reception, which collects the radio waves from the dish and converts them to a signal which is sent through a cable to the receiver inside the building. Also called a low-noise block,[1][2] low-noise converter (LNC), or even low-noise downconverter (LND),[3] the device is sometimes inaccurately called a low-noise amplifier (LNA).[4]
The LNB is a combination of low-noise amplifier, frequency mixer, local oscillator and intermediate frequency (IF) amplifier. It serves as the RF front end of the satellite receiver, receiving the microwave signal from the satellite collected by the dish, amplifying it, and downconverting the block of frequencies to a lower block of intermediate frequencies (IF). This downconversion allows the signal to be carried to the indoor satellite TV receiver using relatively cheap coaxial cable; if the signal remained at its original microwave frequency it would require an expensive and impractical waveguide line.
The LNB is usually a small box suspended on one or more short booms, or feed arms, in front of the dish reflector, at its focus (although some dish designs have the LNB on or behind the reflector). The microwave signal from the dish is picked up by a feedhorn on the LNB and is fed to a section of waveguide. One or more metal pins, or probes, protrude into the waveguide at right angles to the axis and act as antennas, feeding the signal to a printed circuit board inside the LNB's shielded box for processing. The lower frequency IF output signal emerges from a socket on the box to which the coaxial cable connects.
The LNB gets its power from the receiver or set-top box, using the same coaxial cable that carries signals from the LNB to the receiver. This phantom power travels to the LNB; opposite to the signals from the LNB.
The signal received by the LNB is extremely weak and it has to be amplified before downconversion. The low noise amplifier section of the LNB amplifies this weak signal while adding the minimum possible amount of noise to the signal.
The low-noise quality of an LNB is expressed as the noise figure (or sometimes noise temperature). This is the signal to noise ratio at the input divided by the signal to noise ratio at the output. It is typically expressed as a decibels (dB) value. The ideal LNB, effectively a perfect amplifier, would have a noise figure of 0 dB and would not add any noise to the signal. Every LNB introduces some noise but clever design techniques, expensive high performance low-noise components such as HEMTs and even individual tweaking of the LNB after manufacture, can reduce some of the noise contributed by the LNB's components. Active cooling to very low temperatures can help reduce noise too, and is often used in scientific research applications.
Satellites use comparatively high radio frequencies (microwaves) to transmit their TV signals. As microwave satellite signals do not easily pass through walls, roofs, or even glass windows, it is preferable for satellite antennas to be mounted outdoors. However, plastic glazing is transparent to microwaves and residential satellite dishes have successfully been hidden indoors looking through acrylic or polycarbonate windows to preserve the external aesthetics of the home.[5]
The purpose of the LNB is to use the superheterodyne principle to take a block (or band) of relatively high frequencies and convert them to similar signals carried at a much lower frequency (called the intermediate frequency or IF). These lower frequencies travel through cables with much less attenuation, so there is much more signal left at the satellite receiver end of the cable. It is also much easier and cheaper to design electronic circuits to operate at these lower frequencies, rather than the very high frequencies of satellite transmission.
The frequency conversion is performed by mixing a fixed frequency produced by a local oscillator inside the LNB with the incoming signal, to generate two signals equal to the sum of their frequencies and the difference. The frequency sum signal is filtered out and the frequency difference signal (the IF) is amplified and sent down the cable to the receiver:
For the reception of wideband satellite television carriers, typically 27 MHz wide, the accuracy of the frequency of the LNB local oscillator need only be in the order of 500 kHz, so low cost dielectric oscillators (DRO) may be used. For the reception of narrow bandwidth carriers or ones using advanced modulation techniques, such as 16-QAM, highly stable and low phase noise LNB local oscillators are required. These use an internal crystal oscillator or an external 10 MHz reference from the indoor unit and a phase-locked loop (PLL) oscillator.
With the launch of the first DTH broadcast satellite in Europe (Astra 1A) by SES in 1988, antenna design was simplified for the anticipated mass-market. In particular, the feedhorn (which gathers the signal and directs it to the LNB) and the polarizer (which selects between differently polarized signals) were combined with the LNB itself into a single unit, called an LNB-feed or LNB-feedhorn (LNBF), or even an "Astra type" LNB. The prevalence of these combined units has meant that today the term LNB is commonly used to refer to all antenna units that provide the block-downconversion function, with or without a feedhorn.
It is common to polarize satellite TV signals because it provides a way of transmitting more TV channels using a given block of frequencies. This approach requires the use of receiving equipment that can filter incoming signals based on their polarization. Two satellite TV signals can then be transmitted on the same frequency (or, more usually, closely spaced frequencies) and provided that they are polarized differently, the receiving equipment can still separate them and display whichever one is currently required.
Throughout the world, most satellite TV transmissions use vertical and horizontal linear polarization but in North America, DBS transmissions use left and right hand circular polarization. Within the waveguide of a North American DBS LNB a slab of dielectric material is used to convert left and right circular polarized signals to vertical and horizontal linear polarized signals so the converted signals can be treated the same.
The probe inside the LNB waveguide collects signals that are polarized in the same plane as the probe. To maximise the strength of the wanted signals (and to minimise reception of unwanted signals of the opposite polarization), the probe is aligned with the polarization of the incoming signals. This is most simply achieved by adjusting the LNB's skew; its rotation about the waveguide axis. To remotely select between the two polarizations, and to compensate for inaccuracies of the skew angle, it used to be common to fit a polarizer in front of the LNB's waveguide mouth. This either rotates the incoming signal with an electromagnet around the waveguide (a magnetic polarizer) or rotates an intermediate probe within the waveguide using a servo motor (a mechanical polarizer) but such adjustable skew polarizers are rarely used today.
The simplification of antenna design that accompanied the first Astra DTH broadcast satellites in Europe to produce the LNBF extended to a simpler approach to the selection between vertical and horizontal polarized signals too. Astra type LNBFs incorporate two probes in the waveguide, at right angles to one another so that, once the LNB has been skewed in its mount to match the local polarization angle, one probe collects horizontal signals and the other vertical, and an electronic switch (controlled by the voltage of the LNB's power supply from the receiver: 13 V for vertical and 18 V for horizontal) determines which polarization is passed on through the LNB for amplification and block-downconversion.
An LNB with a single feedhorn but multiple outputs for connection to multiple tuners (in separate receivers or within the same receiver in the case of a twin-tuner PVR receiver). Typically, two, four or eight outputs are provided. Each output responds to the tuner's band and polarization selection signals independently of the other outputs and "appears" to the tuner to be a separate LNB. Such an LNB usually may derive its power from a receiver connected to any of the outputs. Unused outputs may be left unconnected (but waterproofed for the protection of the whole LNB).
A special type of LNB (not to be confused with Quad LNB) intended for use in a shared dish installation to deliver signals to any number of tuners. A quattro LNB has a single feedhorn and four outputs, which each supply just one of the Ku sub-bands (low band/horizontal polarization, high band/vertical polarization, low/vertical and high/horizontal) to a multiswitch or an array of multiswitches, which then delivers to each connected tuner whichever sub-band is required by that tuner.[8]
Although a quattro LNB typically looks similar to a quad LNB, it cannot (sensibly) be connected to receivers directly. Note again the difference between a quad and a quattro LNB: A quad LNB can drive four tuners directly, with each output providing signals from the entire Ku band. A quattro LNB is for connection to a multiswitch in a shared dish distribution system and each output provides only a quarter of the Ku band signals.
eebf2c3492
The SLM-771 is an L-Band Satellite Level Monitor designed to detect measure and report the receiving level of any RF signal from 5MHz up to 2.5GHz. Use it for early warning of satellite dish and LNB signal degradation due to snow loading, bug & bird intrusions, dish misalignment due to wind or movement, and any increase in LNB loss for whatever reason. It will alert you to the signal reduction before a system failure occurs.
Convert C Ku Band Signal
Download Zip https://shurll.com/2wIzXd
A low-noise block downconverter (LNB) is the receiving device mounted on satellite dishes used for satellite TV reception, which collects the radio waves from the dish and converts them to a signal which is sent through a cable to the receiver inside the building. Also called a low-noise block,[1][2] low-noise converter (LNC), or even low-noise downconverter (LND),[3] the device is sometimes inaccurately called a low-noise amplifier (LNA).[4]
The LNB is a combination of low-noise amplifier, frequency mixer, local oscillator and intermediate frequency (IF) amplifier. It serves as the RF front end of the satellite receiver, receiving the microwave signal from the satellite collected by the dish, amplifying it, and downconverting the block of frequencies to a lower block of intermediate frequencies (IF). This downconversion allows the signal to be carried to the indoor satellite TV receiver using relatively cheap coaxial cable; if the signal remained at its original microwave frequency it would require an expensive and impractical waveguide line.
The LNB is usually a small box suspended on one or more short booms, or feed arms, in front of the dish reflector, at its focus (although some dish designs have the LNB on or behind the reflector). The microwave signal from the dish is picked up by a feedhorn on the LNB and is fed to a section of waveguide. One or more metal pins, or probes, protrude into the waveguide at right angles to the axis and act as antennas, feeding the signal to a printed circuit board inside the LNB's shielded box for processing. The lower frequency IF output signal emerges from a socket on the box to which the coaxial cable connects.
The LNB gets its power from the receiver or set-top box, using the same coaxial cable that carries signals from the LNB to the receiver. This phantom power travels to the LNB; opposite to the signals from the LNB.
The signal received by the LNB is extremely weak and it has to be amplified before downconversion. The low noise amplifier section of the LNB amplifies this weak signal while adding the minimum possible amount of noise to the signal.
The low-noise quality of an LNB is expressed as the noise figure (or sometimes noise temperature). This is the signal to noise ratio at the input divided by the signal to noise ratio at the output. It is typically expressed as a decibels (dB) value. The ideal LNB, effectively a perfect amplifier, would have a noise figure of 0 dB and would not add any noise to the signal. Every LNB introduces some noise but clever design techniques, expensive high performance low-noise components such as HEMTs and even individual tweaking of the LNB after manufacture, can reduce some of the noise contributed by the LNB's components. Active cooling to very low temperatures can help reduce noise too, and is often used in scientific research applications.
Satellites use comparatively high radio frequencies (microwaves) to transmit their TV signals. As microwave satellite signals do not easily pass through walls, roofs, or even glass windows, it is preferable for satellite antennas to be mounted outdoors. However, plastic glazing is transparent to microwaves and residential satellite dishes have successfully been hidden indoors looking through acrylic or polycarbonate windows to preserve the external aesthetics of the home.[5]
The purpose of the LNB is to use the superheterodyne principle to take a block (or band) of relatively high frequencies and convert them to similar signals carried at a much lower frequency (called the intermediate frequency or IF). These lower frequencies travel through cables with much less attenuation, so there is much more signal left at the satellite receiver end of the cable. It is also much easier and cheaper to design electronic circuits to operate at these lower frequencies, rather than the very high frequencies of satellite transmission.
The frequency conversion is performed by mixing a fixed frequency produced by a local oscillator inside the LNB with the incoming signal, to generate two signals equal to the sum of their frequencies and the difference. The frequency sum signal is filtered out and the frequency difference signal (the IF) is amplified and sent down the cable to the receiver:
For the reception of wideband satellite television carriers, typically 27 MHz wide, the accuracy of the frequency of the LNB local oscillator need only be in the order of 500 kHz, so low cost dielectric oscillators (DRO) may be used. For the reception of narrow bandwidth carriers or ones using advanced modulation techniques, such as 16-QAM, highly stable and low phase noise LNB local oscillators are required. These use an internal crystal oscillator or an external 10 MHz reference from the indoor unit and a phase-locked loop (PLL) oscillator.
With the launch of the first DTH broadcast satellite in Europe (Astra 1A) by SES in 1988, antenna design was simplified for the anticipated mass-market. In particular, the feedhorn (which gathers the signal and directs it to the LNB) and the polarizer (which selects between differently polarized signals) were combined with the LNB itself into a single unit, called an LNB-feed or LNB-feedhorn (LNBF), or even an "Astra type" LNB. The prevalence of these combined units has meant that today the term LNB is commonly used to refer to all antenna units that provide the block-downconversion function, with or without a feedhorn.
It is common to polarize satellite TV signals because it provides a way of transmitting more TV channels using a given block of frequencies. This approach requires the use of receiving equipment that can filter incoming signals based on their polarization. Two satellite TV signals can then be transmitted on the same frequency (or, more usually, closely spaced frequencies) and provided that they are polarized differently, the receiving equipment can still separate them and display whichever one is currently required.
Throughout the world, most satellite TV transmissions use vertical and horizontal linear polarization but in North America, DBS transmissions use left and right hand circular polarization. Within the waveguide of a North American DBS LNB a slab of dielectric material is used to convert left and right circular polarized signals to vertical and horizontal linear polarized signals so the converted signals can be treated the same.
The probe inside the LNB waveguide collects signals that are polarized in the same plane as the probe. To maximise the strength of the wanted signals (and to minimise reception of unwanted signals of the opposite polarization), the probe is aligned with the polarization of the incoming signals. This is most simply achieved by adjusting the LNB's skew; its rotation about the waveguide axis. To remotely select between the two polarizations, and to compensate for inaccuracies of the skew angle, it used to be common to fit a polarizer in front of the LNB's waveguide mouth. This either rotates the incoming signal with an electromagnet around the waveguide (a magnetic polarizer) or rotates an intermediate probe within the waveguide using a servo motor (a mechanical polarizer) but such adjustable skew polarizers are rarely used today.
The simplification of antenna design that accompanied the first Astra DTH broadcast satellites in Europe to produce the LNBF extended to a simpler approach to the selection between vertical and horizontal polarized signals too. Astra type LNBFs incorporate two probes in the waveguide, at right angles to one another so that, once the LNB has been skewed in its mount to match the local polarization angle, one probe collects horizontal signals and the other vertical, and an electronic switch (controlled by the voltage of the LNB's power supply from the receiver: 13 V for vertical and 18 V for horizontal) determines which polarization is passed on through the LNB for amplification and block-downconversion.
An LNB with a single feedhorn but multiple outputs for connection to multiple tuners (in separate receivers or within the same receiver in the case of a twin-tuner PVR receiver). Typically, two, four or eight outputs are provided. Each output responds to the tuner's band and polarization selection signals independently of the other outputs and "appears" to the tuner to be a separate LNB. Such an LNB usually may derive its power from a receiver connected to any of the outputs. Unused outputs may be left unconnected (but waterproofed for the protection of the whole LNB).
A special type of LNB (not to be confused with Quad LNB) intended for use in a shared dish installation to deliver signals to any number of tuners. A quattro LNB has a single feedhorn and four outputs, which each supply just one of the Ku sub-bands (low band/horizontal polarization, high band/vertical polarization, low/vertical and high/horizontal) to a multiswitch or an array of multiswitches, which then delivers to each connected tuner whichever sub-band is required by that tuner.[8]
Although a quattro LNB typically looks similar to a quad LNB, it cannot (sensibly) be connected to receivers directly. Note again the difference between a quad and a quattro LNB: A quad LNB can drive four tuners directly, with each output providing signals from the entire Ku band. A quattro LNB is for connection to a multiswitch in a shared dish distribution system and each output provides only a quarter of the Ku band signals.
eebf2c3492
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