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Adjusting the Polar Mount and other info to install a tracking satellite system

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  • Adjusting the Polar Mount and other info to install a tracking satellite system

    Introduction: Welcome to the world of tracking satellite systems!!! There is much more to the world of satellite TV than fixed little dishes that look at only one satellite. It takes a little more effort to install a tracking satellite system. However, with a good understanding of the equipment options and if the adjustments on the tracking/tuning page are performed in the correct order, you will have a dish that tracks perfectly and a bigger window to the world. You should have an unwarped satellite dish, and a perfectly vertical mounting pole, it will make things easier. This site deals with prime focus (or center focus) satellite dishes, meaning incoming signals are directed to a point.at the center of the dish. It is impossible to cover every detail in a site such as this, otherwise the pages would never load!! Some details, such as using UV resistant tie wraps to tidy your cabling is common sense.

    And for pole installation, covered in detail on a companion page, is ground poles in concrete and mounts on concrete pads as well as a brief discussion on wind loading. For an azel mount, i.e. not a polar tracking mount, proceed directly to the azel mount setting notes. NOTE: Azel mounts are used when you have no intention of moving the dish to another satellite as in the case of a system feeding video into a hotel or apartment complex or other similar cable distribution system; if this is the case, then use an azel mount as they are more stable than polar mounts.

    Other good information on companion pages is a nice, detailed section on noise which includes discussion on signal loss due to rain fade and free space travel, earth thermal noise and terrestrial interference (TI) andShortcut to Tracking/Tuning Section.
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    GENERAL OVERVIEW:
    Television satellite signals originate from a single 'uplink' facility and are transmitted to a communications satellite orbiting 22,300 miles above the earth's equator. These type orbiting communications satellites are considered to be 'parked' in orbit; though in reality they travel from west to east but appear stationary to an observer on Earth because their speed is the exact speed of the Earth's rotation thus they are termed geostationary satellites. The overwhelmingly common receive frequency of satellite transmissions, for video purposes, are either in the C-band (frequency range from 3.7 to 4.2 gigahertz) or in the Ku-band (10.7 to 11.7 Ghz and 11.7 to 12.75 Ghz). New generation satellites are being built with Ka-band capability (22Ghz) and a very few, older specialty satellites are in the lower frequency S-band. After receiving the signals from earth, the satellite amplifies the signals then rebroadcasts them, or 'downlinks', back to earth in a predetermined beam pattern commonly called a 'footprint'. The calibration of the footprint is in EIRP (effective irradiated power) and its units are in dBw (decibel watts).

    The downlinked signal from the satellites, upon reaching the earth, is very weak not only because of the great distance the signal has traveled but also because of the 'spreading' effect of the signal from a point source at the satellite to a regional image at its footprint. To begin the process to receive this signal, in effect, a satellite dish is a passive amplifier in that it 'collects' the weak signals from space, thus the bigger the dish the greater the signal amplication which is why a larger dish is required to receive satellite signals that are weak into your receiving location. A satellite dish collects these weak signals and focuses (reflects) the energy to a central spot known as the focal point or focus. All satellite dishes are designed according to a family of mathematical formulae known as parabolas (dish design formula). All incoming signals to a parabolic reflector are 'bounced' to the same point - this point is known as the focus (or focal) point of the dish. Ideally, all incoming signals from the orbiting satellite are reflected to the focal point. If the dish is properly installed and has no major surface irregularities, the reflected incoming energy will be tightly concentrated at the focus, therefore maximizing dish gain. Note that an offset dish is simply a section of the total parabola.
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    CHOOSING A DISH:The obvious statement is that the bigger the dish the more signal it can gather and the weaker satellite signals it can pull in. So your first consideration in choosing a dish is to make a list of satellites you are interested in receiving and look at their footprints then calculate, using a link budget program, the size dish required to receive them. If you are interested in a DBS (direct broadcast system) satellite and only have interest in receiving the programming from that satellite only then purchase and install the recommended system from your local satellite store. If you have interest in receiving multiple satellites then be sure to get a C and Ku-band compatible dish. If you are buying a used mesh satellite dish, be sure it has the smaller diameter perforations or a significant portion of Ku signals will pass through the dish. Do not waste your time buying a fiberglass dish as that is early technology and will be guaranted to have C-band only mesh embedded within. If you have consideration to purchase a solid metal dish, or one piece mesh dish, stand aside from it and sight across it to be sure it is not warped - if so, do not purchase it regardless of the price. In buying a new dish, a solid dish will not necessarily have a greater efficiency rating than a mesh dish; look at the dish specs and see its efficiency rating which is the percent of signal that hits the dish is actually reflected into the feed - the greater the efficiency rating, the more gain the dish will have. In considering a buttonhook feed support or leg feed support dish, today's feeds and LNBs are so compact and lightweight (as compared to the equipment from the early days of the industry) that a buttonhook will provide sufficient support. On the other hand, a feed supported by legs will always be more stable in winds. In another consideration of mesh vs.solid dish, at wind velocity of about 50mph the two offer the same resistance to wind forces; a mesh dish is easier for the actuator to 'push' around though on smaller diameter dishes (less than 2.5m) today's actuators handle a solid dish with minimal problems. For more technical information on choosing a dish, go to the side lobe discussion page. To look at the dish size required for your site, if your know your EIRP, go to the EIRP/dish size charts page. To make a complete link budget which includes your LNB rating, dish efficiency parameters, latitude and longitude, slant angle, bandwidth and rain factors in the equation (program), go to this link, Swedish Microwave Link Budget program; (this is a real easy program to use and an example output of its TV screen display is seen here).
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    The next consideration in dish selection is the F/D ratio of the dish. In general, the less the F/D, the deeper the dish, the lower the gain and the greater the rejection of unwanted signal. Thus the choice of satellite dish can assist in rejecting terrestrial interference in that the deeper the dish the more narrow will be its acceptance of satellite signals and the less chance unwanted signals will enter the feed assembly. A dish is considered deep with F/D ratios of 0.25 to 0.32 and is considered shallow with F/D ratios of 0.33 to 0.45. So choose a high gain, shallow dish if you have no fears of TI entering your system. Remember that the more shallow the dish the closer to the dish thescalars are set on the feed.
    One thing to remember, the deeper the dish and the larger the dish, the narrower is the central reception beam pattern (see side lobe discussion page); the implications of this is that the effect on installation is that the narrower a main beam then the more difficult it is to focus on the satellite while tuning a dish. This is not appreciably noticeable under strong footprints or sizes under 3.0m, but is noticable when tracking Ku satellites and when using a larger dish. A larger dish, for instance a 4.0m diameter dish, has a much more narrower main beam pattern than a 3.0m dish and you have to be more 'dead on' the satellite when tracking them so your elevation/declination/north-south adjustments are more critical. If you use a 5.0m dish it is real easy to loose a satellite while making mount adjustments (due to the narrow receive beam pattern) so choose the highest gain, shallowest dish when possible.
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    FEEDHORN: (For assembly instructions.) At the focal point, the received satellite signals are gathered by, i.e. pass into, an apparatus called the 'feed', or feedhorn. The feedhorn is located exactly where the mathematics of the parabola, used in the dish design (dish design formula), determine the focal point to be located. The feedhorn is designed to accept incoming satellite signal while rejecting unwanted signal (such as signals bounced from nearby walls into the dish or signals from nearby telephone and/or television towers that might enter the dish) and it is designed to select signal polarity and to efficiently direct the gathered signal towards (into) the LNB (low noise, block downconverter, amplifier). Feedhorns have a scalar plate, composed of concentric rings, which surround the feed throat. Scalar rings are designed to accept desired signals and assist in rejecting undesired frequencies - notice the difference in scalars on a C-band feed and that of a Ku-band feed. The position of the scalar around the feed throat determines the feedhorn's field of view and, to some extent, its acceptance or rejection of unwanted signal (scalar settings for deep and shallow dish). The proper scalar location is determined by dish design mathematics and is the F/D setting. Inside the feed throat is a polarity probe which is the acual antenna that receives signals from a satellite. The feed throat and probe are designed for efficient reception of specific microwave frequencies and is why they should never be tampered with; they are designed to pass (channel) frequencies to the LNB with minimal signal loss or distortion.
    A single LNB feedhorn is called a polarotor and if you have a C-band system only then you are using a C-band polarotor and if you have a Ku-band system only then you are using a Ku-band polarotor. A small motor is mounted atop the polarotor that moves the polarity probe, inside the throat of the feed, and this motor is called the 'servo motor' or 'servo' for short. Satellite signals are transmitted at two polarities and, on command from the satellite receiver, the servo moves the probe so as to accept one polarity and reject the other.
    Satellites use a dual polarization transmission system to allow more efficient use of their equipment, this is termed frequency reuse (for further discussion on frequency reuse). Some satellitemanufacturer's design their satellites to transmit signals in a linear format and some in a circular format and some satellites, such as the Soviet Gorizont satellites, are designed to be linear in one band (C-band) and circular in the other. In a linear format, signal polarization is either horizontal or vertical. In a circular format, signal polarization is either right hand or left hand circular polarization, abbreviated to RHCP/LHCP. To receive circular polarized signals, a circular feed is required - this is often called an 'international feed'. Tofurther understand, for example, in other words, channels 1 and 2 on earth could be transponder 1-horizontal (or RHCP) and transponder 1-vertical (LHCP) in space on the satellite. It is the role of the probe inside the feed (whether linear feed or international feed) to pass one polarity and reject the other; this action by the feed is transparant to the user as it is automatically controlled by the receiver. To pass a polarity, the probe within the fee throat moves to be in line with the desired incoming signal polarization thereby being in-phase with the desired polarization and out of phase with the opposite polarization. The physical act of the probe to be out of phase with the undesired polarization has the effect of disrupting the coherency of that polarization therefore prohibiting it to pass into the LNB. When you change channels, while watching TV, the feedhorn's servo motor rotates the probe, which swings back and forth while switching between the polarized signals (horizontal/vertical channels or RHCP/LHCP channels as appropriate). The act of using one main signal transmission to host two polarizations within that signal is termed 'frequency reuse' and is a technique to double a satellite's channel capacity without adding additional transponders. It is common to use the term 'polarity' when referring to signal polarizations though polarization is the correct term.

    When both polarities of signal are desired to be received at the same time (as in the case for a distribution system as used for a motel or apartment complex or to allow each TV in your home to independently receive all satellite channels) two LNBs are installed on the feed, one for each polarity, and this style feed is called a dual feed, not a dual band feed as band typically refers to either C or Ku signals and a dual feed receives only one band. A dual feed can be for any frequency band; a dual feedhorn does not have a servo motor. Note on a dual feed the LNBs are at right angles (orthogonal) to each other; technically, a dual feed is called an 'orthomode feedhorn'. Another popular type feed is one that accepts multiple frequencies, usually C-band and Ku-band signals, this style feed is called acorotor and is a dual band feedhorn (sample receiver wiring for corotor system). A corotor will have a servo motor to control which incoming signal polarity is passed on to the LNB and it uses both a C-band and a Ku-band LNB. The style feed combining the dual C-band and single Ku-band LNBs (three in total, the Ku uses a servo) is called a 'dual C corotor' (sample receiver wiring for dual C, single Ku system); and a dual C/dual Ku (four LNBs total) is called a 'bullseye' feed. When a feed is designed to receive circular polarity it is called an international polarotor, international corotor, etc.
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    LNB: (For assembly instructions.) Attached to the feed is the LNB (low noise amplifier block downconverer); you will see a probe (post) inside the LNB throat and this probes receives the mechanically vibrating microwaves and converts it into electrical energy to be passed the LNB circuitry then on through the cable to the satellite receiver. Additional to accepting the signal from the feed, the function of the LNB is to both immediately amplify the weak satellite signals from space (received by the dish and passed through the feedhorn probe as gigahertz - a billion cycles per second) and to convert them to an intermediate frequency (megahertz - a million cycles per second) that can be used to travel efficiently thru the coaxial cable attached to the LNB at one end and to the satellite receiver at the other end. Summarizing, satellite frequencies are in the gigahertz (GHz) range and the LNB downconverter output is in the megahertz (MHz) range (the industry standard is to downconvert to the 950-1450MHz range though proprietary systems will use a different downconvert range); inside the satellite receiver, the signal is again downconverted and this time to the frequency range acceptable by your television. Note the downconverted frequencies are in a range, i.e. block, thus the term 'block downconverter'. With a block downconverter, for a twenty-four channel satellite, i.e. twelve transponders, for example, the output of the downconverter contains the information for either the twelve horizontal or the twelve vertical (or RHCP/LHCP) transponders depending on which polarity is being accepted by the feedhorn. Because all twelve channels (in this example of a twelve tranponder satellite) are being carried into the house at one time it is possible to connect multiple satellite receivers to the same satellite dish each with the capability to tune a different channel (a dual feed is used to bring both banks of transponder polarities into the house at the same time when multiple receivers are desired). Block downconversion allows independent channel selection from multiple TV's (each fitted with its own satellite receiver) though, of course, they have to watch the same satellite at the same time. The LNB coaxial cable is typically a 75ohm, RG-6 coaxial cable though for longer travel distances, over several hundred feet, a larger size cable, RG-11, is used because frequencies will attenuate (loose strength) over distance and the object is to deliver a strong signal to the receiver.
    LNBs are rated in noise temperature - the lower the number the better. Noise temperature is a value that indicates the unavoidable, inherent level of background atomic (molecular) motion in an object and this inherent noise (called ambient noise) is in the microwave frequency range. The lower the noise figure, the less ambient noise an LNB injects into the received signal; the lower noise rating of an LNB, the weaker signals it can effectively process. For C-band satellite signals, the noise figure is in degrees kelvin; a value of 25 or lower is today's industry standard. For Ku-band signals, the noise figure is in dB; a value of 1.0 or lower is today's industry standard with 0.7s being very commonly available.. An important fact to remember, natural molecular motion within all matter generates random noise and this random noise 'infiltrates' communication signals so that a received signal must be strong enough to override (rise above) the noise floor created by natural molecular motion. Therefore, the lower noise figure an LNB is rated the weaker satellite signals it can process and thusly the smaller diameter satellite dish it can accomodate. Modern LNB design and circuit technology advancements have lowered the noise figure values of today's LNBs considerably from the early days of the industry so by applying the lowest rated LNB to your system, the better signal processing you will receive and the smaller dish you will need.
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  • #2
    Re: Adjusting the Polar Mount and other info to install a tracking satellite system

    Introduction: On this page is information on cable choice and tips for wiring the servo motor and actuator and for wiring multiple LNBs to the receiver. Also included is info on power passing splitters and in-line distribution amps and discussion on waterproofing your system, the use of feedcovers and installing ground rods and surge protectors.
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    CABLING: Satellite cable is typically called 'all-in-one' or 'direct burial (DBC)'. It is comprised of two RG-6 coaxial cables, a bundle of three color-coded 18, 20 or 22 gauge stranded wires for the feedhorn servo motor, and a bundle of five color-coded stranded wires for the actuator - two 12 or14 gauge for motor control and three 18, 20 or 22 gauge for sensor control. DBC cable is designed to be buried directly into the ground, without being run in conduit, though do not bury the cable until your system is completely connected and performing properly. Buy enough DBC to go up the pole of the dish and out to the center; it is best to make the wire one long piece as splices are a potential future trouble spot for corrosion and entrance for moisture into the system and a splice will also attentuate signal slightly.
    Remember, in wire gauge, the smaller the number then the larger the wire diameter.You will be able to run your system comfortably with 250 feet of cable and should not have a problem at 300 feet. Using a quality receiver receiving strong satellites the RG-6 coax will be 'ok' at 350 feet but it will be close to requiring an upgrade of all stranded wiring. For cable runs (distances) over 300 feet I would go for 12 gauge motor wires and then 20 or 18 gauge sensor wiring (whatever comes in the DBC bundle). If the DBC bundle contains the thicker motor and sensor wires and still contains RG-6 (which is 'ok') then use an in-line signal amplifier on the RG-6 LNB runs if you are encountering weak signals. Over distance, higher frequencies lose power/signal strength/definition, i.e. attenuate,.quicker than lower frequencies so it is conceivable the Ku line would need a line amp whereas the C line would not, all other things being equal. If in doubt, check with your cable supplier and equipment provider for their exact recommendations on length of cable run and size cable/wire to use.
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    Coax cable consists of an inner solid wire, conductor, which carries both the DC voltage to power the LNB and the signal from the LNB to the receiver, and the conductor is surrounded by a plastic or foam insulator (dielectric) and then covered with an outer 'grounding' foil sheath and then covered by an extra braided sheath and then the entire cable is coated by a durable outer plastic covering which is typically black, or pink if plenum fire retardant cable. The dielectric core establishes the impedance of the cable and serves as an insulator between the centr conductor and grounding sheathes; coaxial cable for satellite TV video is a 75 ohm impedance cable. To use RG-6 coax cable, an 'F' endconnector (the same connector used for VCR connections) is attached to each end of the coaxial cable; it is a rather simple procedure which I have performed many times using a pair of pliers to crimp the connector to the cable rather than purchase a speciality coax 'F' connector crimp tool (of course no one recommends this). Be sure that the center conductor does not short out, i.e. touch, to the outer ground sheath as this will definitely kill signal passage and possibly blow the receiver's fuse and could conceiveably damage its internal power supply; just 'skin' back the sheath and clip it so that it can not contact the center conductor - a simple thing to do. If you are using RG-11 cabling be sure to get the 'F'connector for that size cable and even I recommend to use the proper coax crimping tool to install end connectors on RG-11 rather than use pliers. Also use a professional crimp tool when installing for commercial accounts and especially for your customers where plenum cable is employed. When end connectors are installed, pull on them by hand to ensure they are crimped well.
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    For a single LNB feed, only one coax cable is used from the LNB to the receiver. For a dual LNB feed, i.e. no polarotor motor, a coax cable is run from each LNB to the appropriate connection at the back of the receiver - two coax cables are used. For a dual feed going to a single receiver the LNB connections are easy to install as the receiver will have two labeled LNB input coax ports - both a horizontal C-band port and a vertical C-band port. If each LNB output is to go to multiple receivers, i.e. a receiver by the TV in the main room and a receiver by the TV in a bedroom, then you will need to pass each LNB coax through a power passing splitter (in other words, you will need a power passing splitter for each LNB); be sure not to use a regular, in-house, low frequency splitter but a special splitter rated for the range of output frequencies of the LNB. A power passing splitter has dual purposes: to pass DC power (from the receiver) to operate the LNB through one port and to split the output received signal from the LNB for use with multiple receivers. The coax port that passes DC is to be connected to the receiver that controls movement of the dish. Don't forget to place a terminator on any unused splitter ports.

    Two cables are also used for a corotor feed. For a corotor feed going to a single receiver the LNB connections are easy to install as the receiver will have two labeled LNB input coax ports - both a C-band port and a Ku-band port (sample receiver wiring for corotor system). When a dual C/single Ku feed is used then three coax cables are required - the two with the DBC bundle and an extra coax run alongside the DBC bundle (sample receiver wiring for dual C, single Ku system). Two extra coax cables are required when a dual C/dual Ku feed is used for a total of four cables. Because receivers only have two input ports, if three or four coax inputs from the LNB to the receiver are used then you will need an electronic dual polarity satellite control switch for each LNB. It takes in both polarities, i.e. two coaxes, from each LNB then outputs a single coax to the back of the receiver with the polarity of the channel requested by the receiver (as you change channels you are in reality changing polarities and this switch coordinates that information to the LNB). Each set of horizontal and vertical LNBs will require this switch. The electronic switch is powered from the back of the receiver in accordance with receiver manufacturers instructions (see example combiner/control box for C-band LNB in this example receiver wiring for dual C, single Ku system). For receivers that do not have capability to power the switch, the switch can be purchased with an external DC power supply. NOTE: Control switch is placed in-line after the power passing splitter if more than one receiver is used - make a diagram of the coax paths from the LNBs to the receiver if you are slightly confused on the configuration of power passing splitters and control switches. Just remember, you will need a splitter port for each receiver and a control switch per receiver for each set of dual polarities brought down from the feed.
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    One important thing to remember, no cable will forgive you if you put a staple or nail thru it!!, Also coax cable is not forgiving to being kinked so always loop roll coax and never bend it; and nothing kinks easier than RG-59. Damaged coax cable can detrimentally alter signal impedance and cause undue attenuation at certain frequencies (remember that channels are really nothing more than frequencies). I do not recommend using RG-59 cable for anything; it is the 'skinniest' cable available for video application and for some reason it is the favorite (because it is cheapest, I guess) of architects and construction managers to use to prewire a house. Besides kinking easiest and having a flimsy center conductor, RG-59 is a waste of money as it attenuates signal too quickly over any distance to be useful. Do not pay any attention to people that say RG-59 can be used for distances up to 100 feet - RG-59 is a waste of time to use; it kinks easier, has a flimsy center conductor (yes, I know you can purchase RG-59 with thicker center conductors but why bother when RG-6 is available) and it looses signal too quickly. NOTE: For all 'F' connectors - those for LNB connections, for insertions, for VCR connections - use the solid one-piece crimp style and not the two-piece style shown in the RG-59 photo above. A two piece connection is a definite aggravation.
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    In-line and distribution amps are sometimes required for long or undersized cable lengths. If you do have a problem with weak signal from the LNB to the receiver due to long coax distances, i.e. you arrive on a site and find it wired to the dish with undersized coax, such as RG-59, you can put an in-line UHF amplifier (900 -1750 MHz range) on the coax; it is powered by the center conductor of the coax (like the LNB) and typically comes in +10 and +20dB ratings and uses 'F' end connectors. If you are at the limit of RG-6 length, from receiver to dish, and should go to RG-11, you use an in-line amp. As a fact, if you stay under 200 feet on your RG-6 DBC, you will be fine with LNB signal and power to the sensor and actutor assemblies.

    If distribution wiring within the house is prewired with RG-59 (heaven forbid) then use the lower frequency (5-950 MHz) in-line amp on the coax - options include amps powered with an external DC power supply and by in-line DC (check your application and talk with your supplier to determine your need). If you are distributing signal to multiple TVs around a large house, you can use, for instance, a simple 25dB gain distribution amplifier which takes one combined line in and sends one combined line out. For use around a small to medium hotel or apartment complex, you can use an adjustable 60dB gain distribution amp which offers acceptance of combined or individual inputs and offers separate attenuation control for low band VHF, high band VHF and low band UHF. These type units are typically adjustable in 10dB input attenuation units and have individual output gain adjustments and offer front panel feature selectivity and control. NOTE: All frequencies given are for North American designations and products shown are typical examples of market availablity.(Complete list of North American TV Frequencies/Channel Assignments and International TV Frequencies/Channel Assignments).
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    In the DBC bundle, the three 22 gauge wires for the servo motor provide 5V DC power, pulse, and ground connections from the back of the receiver to themotor. For a feed with a polarotor motor, servo control cable is connected at the back of the receiver and to the servo motor. They connect to corresponding terminals on the back of the receiver and usually the red wire is for power (five volds DC), white for pulse (which changes the polarity), and black for ground; these wires pass five volts dc from the receiver to the servo. The receiver uses pulses to keep track of the position of the feedhorn's polarity probe in the feedhorn throat and these wires are the control. Once the receiver is programmed, this control function is transparant to the user and is automatically applied as you switch channels. The servo motor will make a one second 'whirring' noise when you change channels on your receiver - this noise is the motor rotating the polarityprobe inside the feed throat; when you hear this noise, the servo motor is wired correctly. If you do not hear this noise either both polarities on the receiver are set for the same value in which case use the manual polarity control to activate the servo or the wiring is not correct. If the wiring is not correct, switch the wires on the servo until they are properly connected, i.e. until you hear the noise. When connecting any wiring to the dish or receiver, turn off power to the receiver; better yet, unplug the receiver. And do not forget, no cable will forgive you if you put a staple or nail thru it!!
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    (For actuator installation.) The actuator cable bundle of wires consists of two large stranded wires and three smaller wires similar to the three wires for the servo motor. Be sure to connect actuator wires to the appropriate location at the receiver and not confuse them with the connections for the servor control wires. Like the feedhorn servo wires, the three actuator motor sensor wires also provide power, pulse, and ground. In modern systems, a Reed (most common) or Hall-Effect sensor switch is used internally in the actuator motor circuitry (to count rotations of the actuator motor, i.e. to know when to stop the actuator on the satellites you program) and will only require two of the sensor wires, one for pulse and the other for ground - clip or fold back the unused wire. As the shaft rotates the actuator arm, the magnet wheel rotates and the sensor is activated, i.e. makes a 'count' and sends a pulse, every time a magnet passes under the sensor. Actually, the reed switch is 'open' until a magnet passes under it then it 'closes' when it detects a magnet and thereby sends the pulse. The more magnets on the magnet wheel the more counts per arm revolution and the greater accuracy the receiver has in stopping the dish directly where you want it - most important for Ku reception. If, after a lightening storm, your dish is not counting properly, then the reed switch has failed. The two large stranded wires connect to the large wire terminals at the actuator motor and to the motor wire terminals on the back of the receiver. The two large wires provide 24 to 36 volts dc to the antenna actuator's dc motor; do not connect them to any other terminals on the receiver except where it says motor control. Many modern receivers, today, only power 24 volts output and this can be a problem when usingdiameter dishes of 4.0m or greater.When you move the dish to the east or west; if the dish moves in the opposite direction of the direction intended, then simply reverse the two actuator control wires either at the dish or at the receiver. When you set (program) limits for the actuator, according to instructions for your receiver, if the receiver will not let you move the dish, switch motor sensor wires at either the dish or the back of the receiver until the proper sensor wire configuration is achieved - when the receiver will not let you move the dish it is almost always a sensor wiring problem. When connecting any wiring to the dish or receiver, turn off power to the receiver; better yet, unplug the receiver. And do not forget, no cable will forgive you if you put a staple or nail thru it!! And when the job is finished, and the dish tracked, and all cables are in properly functioning order, I use cable/wire tie wraps to tidy up all cable runs along the pole, to the feed assembly and around the actuator (leave a drain loop on cables going into the LNB and wires going into the feed servo motor and actuator - for the actuator allow a large enough loop to allow for actuator movement of the motor as the arm extends and retracts).
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    WATERPROOFING: I use silicon gel on any electrical connections exposed to the elements but for sure do not plug up the drain hole on the actuator motor housing cover. For LNB connections, many LNBs include a black, sticky waterproof compound called Coax-Seal (or whatever) to wrap around the connection, it is designed to breathe but not to pass moisture. If this is not available, or you get tired of fooling with it (it can be a mess), I have regularly squirted silicon gel into the end connector and immediately screwed the connector onto the LNB but remember that silicon gel does not pass moisture so be sure there is no trapped moisture in the connector before doing this - use a blow dryer on the end connector if you are concerned about moisture; you can also apply the gel around the outside of the connector if you wish. Note that if you use ScotchLok connectors for the smaller guage wire connections, such as servo motor lines, that internal to the ScotchLok is silicon gel which is immediately forced around the wires when the ScotchLok is squeezed to make the connection. If you use screw-on wire caps, bathe them in gel and wrap in electrical tape. For in-line insertions, also be sure to waterproof them very well or, better yet, place them in a waterproof plastic box. For all cable connections, whether to the actuator or into the house, leave a little 'sag' in the cable where it enters into the unit or wall so that water will run to the low point and drip off the cable rather than follow the cable into the connection - this is called a 'drip loop'. For instance, before connecting cabling to the feed assembly (servo motor and LNBs), I loosely wrap the cable once around the feed then make the connections as this servese two purposes - it automatically makes a drip loop and also takes the weight of the cable off the connections.
    Regardless of measures taken for waterproofing, the elements will eventually take their toll on your connections so make regular inspections for corrosion and water incursion part of your routine. Replace corroded 'F' connectors - just snip them off and put on a new one; do not bother to clean as usually the corrosion will extend back into the coax and maybe as much as an inch on long neglected connections. Be especially aware that saltwater (salt air) is very damaging to everthing involved with a satellite system - if you live in a salty air environment, in addition to outside electric connections, pay particular attention to corrosion of actuator parts (especially the tube) and mount/cap bolts (they will lock up with corrosion quicker than you think so keep them covered in light oil/grease). Nothing is more aggravating than twisting off a corroded nut/bolt; and remember to spray the bolts that are used in holding the dish together as they are not as high a quality.as mount bolts and they will definitely seize. In regards to the actuator, always install 'this side up' in accordance to manufacturer's instructions; and over time the rubber wiper where the tube goes into the actuator sleeve will loose itsshape (if it is in any kind of sun) and loose completely its wiping capability. Also, in regards to the actuator, I have never been fond of the actuator accordian boots that cover the sliding tube - they always seemed more trouble than they were worth and if you live in a humid environment the tube will become lightly corroded anyway and the boot gives a false sense of security and once you put it on you have a tendency never to check it; I used to sell them to customers that wanted them (easy money) but never put them on display nor promoted them nor installed them - there is no shortcut to regular maintenance.
    If you are worried about water incursion into your signal cable then use 'flooded' coax - it contains a water resistent, clear, sticky gel beneath the plastic jacket (a mess to make connections with but will do the trick) and, in the worst case scenario, put all outdoor cable in PVC conduit. To tell the truth, though, in the ten years in Houston (high humidity, relatively close to the coast, high rainfall amount, poor yard drainage) when we would deinstall a system and dig up the DBC cable, it was dirty but none the worse for wear so we never put anything in conduit for below ground applications unless a client really insisted on it. We would put outside cabling in conduit up a wall, commerical installations, etc, but that was to protect the cable from man and not from weather. Now, rusty bolts is a different story - that was always a problem.
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    FEEDCOVERS:This is a good time to talk about feed assembly covers. I never use them because I use a commercial CalAmp C-band LNB with the tiny power indicator light on it and I like to look up at my dish and see that the LNB is powered (as crazy as that sounds). However, I always install covers for customers. Also, for my personal systems, I leave off the elbow on the feed and connect the LNB straight into the feed (for the extra gain lost by using the elbows) so that feed covers will not fit over the finished assembly. I also live in a temperate zone and feel it is better in the summer to leave the cover off rather than bake the LNBs; when I worked in Saudi Arabia we always left them off. Imagine it being a hot day and in the car with the windows rolled up - that is what it is like under the feedcover. Plus, the warmer is the LNB, the more ambient noise it will have and the greater its noise temperature will be thus reducing its effectiveness. Although LNBs are coated (externally) with heat resistent material (enamels, paint, whatnot) it is still not good to heat them up. These are just my personal preferences as you can see just as many dishes with feed covers than not and there seems not to be any pattern in service calls from one arrangement to the other as far as LNB failure is concerned. Another reason I leave the cover off is so that insects will not make a home under them. When winter comes, and inclement weather, ice and precipitation, is the norm, I do cover the feed assembly with a plastic bag for whatever period I think is important to avoid any water expansion due to freezing and the effects it may have on connections though I like to think I have made all connections impervious to water incursion. For regular spring rains, even when I lived in the rain forest of Costa Rica, I never bother with a feed cover as I want everything to dry as quickly as possible and to avoid a humid condition under the feed cover.
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    GROUND ROD/SURGE PROTECTION:I personally do not usually fool with ground rods though everyone recommends it - homeowners insurance should cover your satellite equipment - andcertainly the lightening strike map showed I was in a high probablity area for lightening when I lived in Houston. However, I always unplug all my electronics in the house, including stereo, TV, microwave, satellite equipment, etc., during any lightening storms or severe weather. That foolishness said (as some would say), the theory of ground rods is to direct spurious and anomalous electrical energy that may 'strike' your satellite dish, or near it, into the ground and not into the cabling which leads to indoor equipment. Grounding rod or not, a strike on the dish will kill dish electronics, i.e. LNB, though I have never heard of it affecting the servor motor except in direct hits. If, after a lightening storm, your dish is not counting properly, then the reed switch in the actuator motor has failed. A strike between the dish and the house (or nearby) can radiate electrical energy away from the strike point (depending on soil conductivity) and can thus enter buried cabling and will then travel both directions - into the house and back toward the dish. So a ground rod is really good for something at the dish and not between the house and dish therefore try to put your dish in a shelter place where it is not the greatest attraction to lightening. The ground rod for your satellite dish should be of equal length as recommended by the building code in your area
    for ground rods for electical circuit boxes (where elecrical power enters your house from the service pole) - four to six feet copper, 3/8" to 5/8" diameter should be sufficient if you have no other guidelines to follow, you can buy them in any good hardware or building supply store. For non conductive soils (ex: sandy soils), you may need to use a ground rod up to eight feet in length - check with your local power company. Use a combination grounding clamp/strap at the pole and a clamp at the rod and connect the two grounding clamps withheavy copper braid (strap). You must clean all paint and corrosion from around the satellite pole where the ground clamp/strap is to be attached. Because not all damaging electrical energy enters satellite cabling through the dish, install coax/actuator/servo wire surge protectors inside the house (they can be purchased as a unit toconnect all these wires through one box) and definitely install surge protectors on the AC electrical outlets and use a surge rated multi-outlet power strip to plug you electrical items into. AC surge protectors offer protection from power company transformer problems and line surges. In some countries, it is adviseable to have a combo surge protection/line smoother box to plug you AC cords into; the line smoother protects against voltage falling below specificied values. In reference to commercial installations, including headends and data units, always make every effort to ground the equipment. Don't forget, lightening can also enter a structure through TV antenna and cable company cables as well through telephone lines. All lines where power/signal enter a facility are potential sources of surges and static. In regards to purchasing surge protectors, they never seem to have the one product you really want and I end up installing a combination of products. I always use a surge rated multi-outlet wall plug and if using an extension cord put single outlet surge unit (purchased at the hardware store) on the end of that then have a floor multi-outlet, surge rated strip into which I plug all AC lines of entertainment units (sat receiver, TV, VCRs, etc.). I place great limits on AC surge protection as their power protections are more needed; here in my city the transfomer or power grid or something is always going out so I figure there are spikes in the line all the time. For the computer, it is plugged into a line smoother which boosts weak current and limits high currents and also has phone line filter jacks
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    Comment


    • #3
      Re: Adjusting the Polar Mount and other info to install a tracking satellite system

      READ ALL THESE INSTRUCTIONS BEFORE BEGINNING!!! If the adjustments are donein the correct order, you will have a dish that tracks perfectly. You should have an unwarped satellite dish, and a perfectly vertical mounting pole, it will make things easier. It is suggested to take a TV and the satellite receiver to the dish rather that run back and forth to the house to see what is happening. This site deals with prime focus (or center focus) satellite dishes, meaning incoming signals are directed to a point.at the center of the dish. It is impossible to cover every detail in a section such as this, otherwise the page would never load!! Some details, such as using UV resistant tie wraps to tidy your cabling is common sense.
      For an azel mount, i.e. not a polar tracking mount, proceed directly to the azel mount setting notes. NOTE: Azel mounts are used when you have no intention of moving the dish to another satellite as in the case of a system feeding video into a hotel or apartment complex or other similar cable distribution system; if this is the case, then use an azel mount as they are more stable than polar mounts.
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      INSTALLATION AND TRACKING/TUNING:
      1)Begin with assembly of feedhorn and LNB and checking mounting of the feedhorn. In a center focus (prime focus) system, all legs supporting the feedhorn should be the same length, measure them to be sure, and do any adjustment you can if they are not the same length. Next, check the distance from three different points on the edge of the dish, to the center of the feedhorn, to be sure feed is set to be in the center of the dish. I like to use a focal finder to determine if the feed is aimed at the center of the dish. It is a plastic cup (dual cups, for standard C and Ku-band feed scalar rings) that fits over the innermost scalar ring with a telescoping pointerwhich, when extended, will indicate exactly if the feed is directed to the center of the dish. Remember, even if the feed legs have the same length, that does not mean the feed is centered! You might have to 'bend' the feed into the center of the dish, or adjust the feed support legs for the feed to be centered in the dish. In assembly of the feedhorn/LNB, do not place sealant on feed gaskets - they are meant to be installed dry; and the gasket thickness should be such that there is metal-to-metal contact of the flange contacts after bolt tightening. Do notovertighten bolts, flanges will crack. Leave off the elbows, if you want, and let the LNB(s) stick out to the side - you will gain three dB if you do. If you are using an adjustable noise interference ring (commonly called scalar rings) then set the F/D ratio in accordance with manufacturer's instructions. (If you do not know the F/D ratio, then calculate it using formula in diagram below.) Do notovertighten the screw/bolt that connects the scalar ring to the feed throat as those pieces will also crack. During the feed installation process, be sure do not touch the probe inside the feedhorn nor the probe inside the LNB throat as oil from your fingerprints could interfere with signal reception; and definitely do not bend the probes as they are finely adjusted and any impairment to their shape or position will inhibit their performance.
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      After feed is mounted, use a measuring tape to ensure focal distance of the feedhorn is properly set; the measurement distance can be found in the instruction manual of the dish. Measure from the absolute center of the dish to the front of the polarotor and adjust the distance to as exactly as possible to what the dish instructions say. A 1/8" either way will greatly affect video reception performance on weaker satellites. Imagine wearing eyeglasses and understand that a dish focuses beam energy into the feed as do glasses focus light into your eyes; your eyes and dish can only see as well as they are focused. Dish to feedhorn misalignments of 0.5" reduces collected C-Band signal power by 50% (-3dB)!! (see dB discussion) For instance, the difference in signal gain between a 10 foot dish and 7 foot dish is about 3dB; animproperly aligned feedhorn wastes this gain differential. Without a doubt, an incorrectly placed feedhorn compromises picture quality resulting in detrimental video effects such as picture 'snow' or horizontal lines. If you do not know the focal length, then calculate it. At the end of all feedhorn adjustments and installation, once again check to be sure feed is still centered within the dish. If the face of the scalar is not parallel (equidistant) to the dish face then you will have to carefully bend it into place if the feed legs do not allow for appropriate adjustment .When adjusting the feed, be sure not to touch the probe inside the feedhorn as oil from your fingerprints could interfere with signal reception; in fact, there is no need to remove the plastic cap covering the feed throat probe except to slide on the scalar rings and to measure the focal length, then immediately replace the cap.Now you may connect the coax cable and servo cables to the feed assembly. When connecting any wiring to the dish or receiver, including LNB coax cables, turn off power to the receiver; better yet, unplug the receiver. NOTE: On F/D ratio, the antenna manufacturer's focal length measurement is probably from a center plate (in the middle of the dish) and is not the value used to calculate the curvature of the dish as the center plate will sit atop the center of the dish by some thickness of metal (most center plates are on the order of 1/8" thick); you can use the recommended focal length setting to set the feedhorn location but you can not use it in calculations without adding the thickness of the center plate.
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      2)Install the actuator. Linear actuators, sometimes called 'jacks', consist of a motor and gears with an arm that telescopes in and out of a fixed tube. The purpose of the actuator is to provide stability to the dish while targeting (stopping at) a specific satellite on command from the satellite receiver. The actuator attaches between the polar mount and the satellite antenna. Knowing the satellite arc at your location will tell you what direction the dish needs to travel in order to see the satellites - this will tell you whether the actuator needs to be on the right side of the dish or the left. Attaching the arm will mean having to set the clamp distance on the actuator where it attaches to the mount. The only real way to set this distance is to mount the clamp to the actuator and leave it somewhat loose but not so loose that it slides in travel. Check thatno parts of the actuator rub on the mount during travel - insert washers (spacers) where needed on the actuator bolts to 'lift' the arm away from the mount to prevent any contact with the mount other than the attachment points - this is important as otherwise the natural movement of the actuator as it positions the dish may put itself in a bind and over time this could bend the actuator tube (which is why I do not recommend a one inch tube actuator). There is no set rule on this other than observation as each brand of dish is slightly different in how the actuator attaches and each actuator manufacturer is slightly different in its attachment design. The clamp to the mount will need to be set to a point where it appears that the arm will travel to a point just beneath the lowest look angle it needs to be. This position will probably have to be reset during the tracking process so do not be too fussy on this setting in the beginning. When you feel reasonably sure the retracted position of the actuator will lower the dish sufficiently to be just past the lowest satellite of interest on the horizon then tighten the clamp at the mount axis and program into the receiver the east and west limits of travel.

      To prevent overdrive at the top of the arc, set the actuator limits (in the receiver) before performing any tuning. If you happen to overdrive it at the top of the arc - to the short side (and the dish flops), do not panic; just have someone lift the dish by the lip while you drive it back using the receiver controls and then be sure to check the setting of the limits better. For dish diameter greater that 2.0m always use a 2.0 inch diameter actuator tube (it will serve you much better over time - a one inch tube just does not cut it); for actuator stroke 24 inches and greater a ball actuator is recommended though often more difficult to locate. Acme model actuators consist of a threaded shaft which moves in a threaded collar and are usually rated for loads up to 500 to 700 pounds in the 24 inch length model. A ball actuator features ball bearings instead of a threaded collar and provides smoother movement and is always rated for greater loads than the same length acme actuator - up to 1500 pounds in some cases. However, manufacturing advances in the internal gears and assembly parts have given me confidence to use a 24 inch acme actuator (on mesh dishes) whereas in the early years of the satellite industry they were designs for failure. I would not consider using an acme for actuator requirements over 24 inches in stroke length. To repeat, a one inch tube for dishes over six feet in diameter is a recipe for failure. Actuator manufacturers whose products I like are Venture, Von Weise, and Thomson Saginaw.
      For accurate Ku reception, be sure actuator has a 'high count' sensor, i.e. the more magnet wheels (see diagram in actuator wiring section) the motor has in its sensing 'section' the greater the counts will be per shaft revolution. When choosing an actuator, hold the extension tube in one hand and the body in the other and check for slop in the tube and if too much free movement then choose another brand because that is the amount of movement the dish will experience in wind. Also, some manufacturers ship actuators without middle swivel clamp so be sure to ask if it is included. The better quality actuators also have internal limit settings, called mechanical limits, that I never fool with, but I always buy the brands that build them that way so I recommend you do to as it gives me more confidence in the integrity of their product. The mechanical limits are to be set in case your receiver goes wacky and tries to overdrive the dish so that it would flop (see next paragraph) and the mechanical limits (in the motor housing) will stop the receiver from overdriving the actuator. The mechanical limit switch consists of a plastic cam that trips a microswitch that stops the motor; you set the cam to trip the switch just past the point where the receiver is programmed to stop the dish.
      When the actuator is in the extended position, program that limit to be just past the last satellite of interest; by no means allow the actuator to be extended to the point where it looses its operating leverage thereby causing the dish to 'flop' over to the other side. If you accidentally flop your dish, commonly called 'dumping', then do not panic but simply have a companion lift the dish by its lip while you run the actuator back into its housing and then reset the high side limit - no harm will have been done except to your ego!! All dish controllers are designed to not work when pulses are not received from the actuator motor sensor, i.e. reed switch, and you will see a message saying 'actuator error' (or something similar). If this is the case, do not panic, the greatest probability is that you only need to reverse the pulse and sensor wires and you can do this at the back of the receiver. You must program the east/west limits before beginning tracking procedures otherwise the dish will only move for a few pulses then display the actuator error message. When you move the dish to the east or west; if the dish moves in the opposite direction of the direction intended, then simply reverse the two actuator control wires either at the dish or at the receiver. Remember, after tuning the dish and programming the end satellites, run the dish back and forth between end satellites to be sure actuator sensor counts properly, i.e. to make sure it stops in the same place each time.
      For maintenance, be sure to install the actuator so that the motor is setting in the direction dictated in manufacturer's instructions for water drainage, i.e. rain protection. Over time, if the actuator arm itself becomes slightly corroded with rust then clean gently with fine steel wool and wipe down with a light grease or oil. (For more maintenance ideas see Waterproofing.) Your actuator should last at least five years and probably ten years under normal operating conditions and in most cases will require only normal tube maintenance and annual inspection of wiring connections inside the motor housing for corrosion with the worst problem being to replace the reed switch. However, expect a one inch diameter tube actuator on dishes larger than 2.0m to fail much sooner.
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      3)Set declination/elevation.Move the dish to the highest point in its travel arc, i.e. centering the dish at its zenith. Do this by using the actuator; it can be done by visually looking at the dish. It is now time to set your declination/elevation angles. I use a common carpenter's inclinometer, with magnetic base, to set angles. I like it better than the much more expensive digital inclinometer - especially since I seem to drop it all the time, or forget and leave it on the mount and it gets knocked off to the ground when I am checking the sides or the arc, or forget and leave it on the mount and it gets rained on!! First set the elevation angle, it is measured on the polar axis (sometimes the elevation angle is called the polar axis angle). By elevation, it means the angle in degrees which the dish must be tilted up from the horizon prior to addition of the declination angle. Use az/el charts to get total elevation for your latitude location then substract the declinationvalue for your latitude location and the remainder is the elevation angle to set in this step. (NOTE: The true dish pointing angle is the angle given by all az/el calculation programs and is in fact the sum of the zenith elevation angle (when the dish is at the top of the arc) plus the declination offset angle therefore substract the declination offset angle from the zenith az/el value to get the zenith elevation angle. This is not very critical at this point because you will adjust this angle for best reception later but be as accurate as possible. Next, set the off-set angle on the polar mount, this is the declination. This is an adjustment that tilts the dish 'forwards' at an angle depending on what latitude you live. This adjustment is usually measured on one of the mounts connected directly to the dish, i.e. in the plane of the dish but on its back ring, it depends on your type mount. (In practice, use az/el charts to get total zenith elevation angle, i.e. from the ground to the dish face, for your latitude location and this will be the value to set in the declination adjustment.).
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      4A)Set magnetic deviation.Align the polar axis to the true north-south line for your site (don't forget to adjust for magnetic deviation and to apply the deviation to the correct 'side' of the north needle on the compass) and check that the satellite dish mount cap is vertical on all sides after you tighten it.Tighten the dish on the mount, then loosen it just enough so it will turn. Sometimes, though, the weight of the front of the dish will typically cause it to drop a little so that the mount cap will not be plumb - this is especially true if the pole diameter is in centimeters and the polar cap is in inches; when this happens, I jam a screwdriver between the pole and cap until the cap is plumb then tighten the cap bolts. NOTE: Sometimes the act of tightening mount cap bolts will cause the dish/mount to rotate slightly so after tightening mount cap bolts check that the dish is still aligned to the true north-south line.

      In case you haven't used a compass in a while, remember it's a circle, 360 degrees. Zero is North, East is 90, South is 180 and West is 270. Put the needle on North and pick something in the distance that is in line with North. Make sure the needle moves freely as you turn the compass around and that it is not too close to the dish or anything metal. It may help you to tie a string to the mount and walk out away from the dish. Line your compass with the string and have someone hold it, or tie it to something such as a rod in the ground. When you are behind the dish, this will give you a reference to work with.
      Remember, the dish will look south if you are in the northern hemisphere and will look north if you are in the southern hemisphere and will look straight up if you are on the equator.
      4B)Align azimuth for azel mount satellite.If you are using an azel mount, i.e. not a polar tracking mount, then you will align the azimuth setting to the true heading (not the magnetic heading) of the satellite you are seeking and proceed to azel elevation setting.
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      5A)Program first satellites. Move your television (or spectrum analyzer) and satellite receiver to a table near the dish, if possible; it will save time from running in the house to look at the image then go outside to make dish adjustments. Begin with a satellite that is located as close as possible to due south of your location (if in the northern hemisphere and otherwise locate a satellite due north if you are in the southern hemisphere), this is the highest point of the arc and it is easiest to accurately adjust the polar axis angle (elevation angle) from this position. (A few degrees off will not make much difference because the dish moves almost flat in the center of arc.) It is usually best to look for a C-band satellite when you begin (if you are working with a C/Ku system), they will be easier to find than a Ku satellite; however, try a Ku satellite because the accuracy your system will have will be much greater if you tune to Ku satellites although Ku satellites are more difficult to find initially - if you have a Ku system only, of course, look for the nearest Ku satellite due south of your installation. (See Side Lobe Discussion for why Ku satellites are more difficult to track.) The quickest way to track a dish, though, is to program all the C-band satellites first then put in the Ku satellites. If the elevation setting is way off or if the magnetic adjustment is way off, you might not find this first satellite. If so, while having the dish located at the highest point of the arc (due south), you have to turn the entire polar mount on the ground pole until you 'hit' the satellite.- this is where using a spectrum analyzer comes in handy. If you do not have a spectrum analyzer (and I did not for years), then set the receiver to 'scan' mode (you will find a button, switch, on the back of the receiver to accomplish this) so it will rapidly scan the channels and you will be sure not to miss an active transponder as it flashes across your TV screen. If your first satellite is not at the top of the arc, or near to it, continue with this procedure until you locate the top of the arc satellite; always program all satellites you find into the receiver, as you find them, and do not forget to use the skew adjustment to fine tune polarity. When you find a satellite, take the receiver off scan mode and check with a current copy of your local satellite TV guide to confirm which satellite you have found. Remember to adjust the polarity to its best at each satellite and program into receiver.
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      5B)Program azimuth-elevation satellite.If you are using an azel mount, i.e. not a polar tracking mount, then you will have aligned the azimuth setting to the true heading (not the magnetic heading) of the satellite you are seeking and in this step you will raise (lower) the elevation setting to the elevation of the satellite you are seeking and you will be finished with your installation except for fine tuning the two settings.
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      6)Fine tune north-south alignment (tracking the sides of the arc).After you are satisfied with the elevation and declination adjustment at the top of the arc, it is time to program middle and end of the arc satellites. This is where most people fail. DO NOT adjust any elevation angles on the mount at this point! Choose the side where the satellites are lowest on the horizon and move the dish, using the actuator, to each consecutive satellite from the top of the arc to the lowest one you can find. Peak the dish on the satellite, the lowest on the arc you can locate, using the actuator. Next, push or pull upwards and downwards on the dish (remember not to stand in front of the signal so as to block incoming signal). You don't have to use much force, just a bit to see if the signal gets better or worse when you push/pull on the dish. What you are actually doing is changing the elevation angle a bit. For instance, if the dish is pointing at a satellite to the east of center and you have to push up on the dish to get a better signal, then the elevation angle must be adjusted higher. At this time, you adjust this by turning the entire mount to the east (to the west if you are in the southern hemisphere) and not by adjusting either the elevation or declination angles! Most errors in tuning a satellite system are due to improper north/south alignment. To repeat, if the dish needs to be pulled down (lowered) for a better signal, then turn the mount the opposite direction (towards the higher point on the arc) and if the dish needs to be pushed up (lifted) to get a better signal, then rotate the entire mount away from the top of the arc. BE SURE TO MARK, using a piece of chalk or place a strip of masking tape on the pole and mount cap, the pole and mount to know exactly where your original position is - rotate the mount only SLIGHTLY (no more than 1/16inch ). Note from thechart, a very small movement on the pole can translate to a very large amount in degrees of rotation. Best method to rotate the dish is to barely loosen the cap bolts then stand in front of the dish and grasp the lip of the dish with both hands and gently move the dish in the desired direction. Then retighten the cap bolts, checking that mount cap is still plumb, and mark the new cap position on the pole. After moving the mount, use the actuator and move the dish east/west as necessary to peak the signal on each satellite encountered. Observe the results on a satellite at each end of the arc and at the top of the arc after each mount adjustment. Repeat this procedure until the dish has the correct north/south alignment, as you do this you should be able to locate the satellite lowest on the arc if you could not find it at first. Always go back to the top of the arc to make sure it is still in view and always check the satellites on the low ends of the arc. If you peaked the dish for center, and then for one side, and the center is still in view then the other side should be very close, of course, this will depend on the ground pole being vertical and offset angle/elevation angle settings.
      Remember, when you rotate the mount on the pole, each satellite will need to be reprogrammed into the receiver as rotating around the pole changes the location of the satellite in respect to the memory of actuator setting (per satellite) internal to the receiver. If, when the end of the arc satellite is in view and the top of the arc satellite is not in view, then the elevation angle adjustment is grossly wrong and you have to readjust the elevation angle and repeat the procedure until you get one side of the arc, including the top, all in view and programmed into the receiver. If you suspect your elevation adjustment is grossly wrong, go back to the first satellite, the one at the top of the arc, and adjust the elevation so that the satellite remains in view when the mount is set back to its true north-south axis then repeat procedures of this step. Ideally, what you want in this step is to be able to see the entire arc (even if the dish is not hitting center on either ends or the top); what you are looking for at this time is a compromise on the north/south setting that allows all satellites, from end to end, to be in view. After this compromise is reached then it is time to fine tune elevation/declination settings. Always, as you move the dish from side to side, stop at a couple of satellites in the middle and at the top to monitor your adjustment effects.
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      7)Fine tune elevation.Once again, lift and pull the dish on the satellites on the low ends of the arc to see which direction produces a better picture (stronger signal). As stated in previous step, lifting and lowering the dish has the momentary effect of making elevation changes to the mount - if you are using a spectrum analyzer to tune the dish then you will be able to visibly see if the signals are weaker or stronger as you lift and lower the dish otherwise watch the image on the TV screen and/or the strength meter on the receiver. If lifting the dish on both sides produces a better signal, including the center satellite (or at least does not affect the center) then slightly increase the elevation angle. If lowering the dish on both sides produces a better signal, including the center satellite (or least does not affect the center) then slightly reduce the elevation angle. Keep track how much you turn the bolt(s) that adjust the elevation angle so in case you overadjust you know how much to 'back up' the adjustment. A rule of thumb is to only move the elevation adjustment bolts no more than a quarter of a turn per adjustment. After each adjustment quickly check all satellites to see if they are better or worse. You might have to go from side to side and repeat the elevation adjustment steps before the dish tracks to your satisfaction.
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      8)Fine tune declination (end of the arc adjustments).If, and ONLY if, you can not get both sides to peak, and both sides would be too low or too high while the center remains the same; you can then do a small adjustment of the declination angle to get the two sides into peak with the top. BUT, only do this if you can confirm that both sides are low or high while the center remains the same. If the dish is too high on the sides (arc ends), but fine in the center, the declination angle is too low so increase the declination and decrease the elevation angle the same amount. The two adjustments will cancel each other in the center of the arc while tracking lower on the sides. Conversely, if the dish is too low on the sides (arc ends), but fine in the center, the declination angle is too high so decrease the declination and increase the elevation angle the same amount. One thing to remember, the satellite dish also receives random noise, earth thermal noise, from the earth in addition to signals from space. Random earth noise is something we can not control and is generated by internal molecular motion of all matter; therefore, when the dish is at its peak, it is receiving less thermal noise than when it is positioned looking out on the horizon. Therefore, lower end satellites will always show a weaker signal than higher arc satellites - all things being equal. If your satellites of interest are on the low end of the arc and those satellites are delivering weaker signals to your system after your best efforts at tuning the dish, then you will require a larger diameter dish though installing the best rated LNB you can afford might overcome this. Note, a larger diameter dish will take in more thermal noise, of course, but the increased satellite signals it will gather are more significant than the increased thermal noise it will pick up. The side lobes (see side lobe discussion) of a larger dish are smaller in comparison to its main lobe so a larger dish receives less per cent noise per signal as compared to a smaller dish and, as the chart indicates, consequently shows to receive less noise than a smaller dish. so that a larger diameter satellite dish is the clue to overcoming weak signals from low end of the arc satellites.
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      9)Using spectrum analyzer. You should now have a perfectly peaked dish and you can check this using a spectrum analyzer although I have installed many systems to complete customer satisfaction without an analyzer. A spectrum analyzer displays frequency vs. amplitude of all carriers, per polarization, per satellite. If you used Ku-band satellites for peaking, it will be as good as it can be. If you used C-band satellites, you will want to repeat the fine tuning steps using Ku satellites. As you go from satellite to satellite in the tuning process, note the weakest channels on each satellite and see what effect your adjustment process has on them. If at the end of the adjustmentprocess and there are still weak channels then check the eirp footprints (eirp for Eastern Hemispheresatellites, for Western Hemisphere satellites) for that satellite and channel (transponder) to see if they are aimed into your region and, if possible, use a spectrum analyzer to look at the weak channels (transponders) and see how weak they really are in comparison with the stronger channels on other satellites with similar eirp patterns to see if ground effects are playing a role in reception and/or if your tuning is that much off. Also compare weak channels to strong ones on the same satellite to see if the weak channels might belong to a broadcaster that is simply not uplinking a strong signal or is uplinking a half transponder signal. All these actions will give you peace of mind that you have done the best job possible and will tell you if what you need is a bigger dish to receive the weaker channels. On older satellites it is a fact that some transponders age quicker than others and thereby are inherently weaker. A spectrum analyzer allows more quantative understanding of the variations in transponder reception per satellite than does monitoring each channel with a TV. In regards to final tracking of the dish, in general, it is said that Ku reception is three times more sensitive to tracking errors than is C-band and tracking Ku satellites is really where a spectrum analyzer comes in handy. The last thing to do after satisfying yourself that your installation is its best, apply VNR (video noise reduction) and/or bandpass filters, as built into your receiver, to any channels which still show a few sparkles. A satellite receiver with a good set of internal filters (especially Chapparal brands) will increase video quality by a 'grade', i.e. make a 'B' grade image to an 'A' grade. If you are using a frequency tunable receiver (again, Chaparral), then try adjusting the center frequency and frequency range of any channel that is giving you a problem especially if you think they might be half transponder transmissions or transmissions on non standard transponder bandwidths, i.e. a downlink on a 54MHz transponder.
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      SUMMARY: Find top satellite first then satellite at lowest arc position then program satellites in the middle between these two then program your way down to the lowest satellite at the other end of the arc. Always adjust north-south axis before making elevation/declination adjustments. Always adjust elevation before making any declination adjustments. To determine whether to make elevation or declination adjustment, program as many satellites as possible into satellite receiver then use this chart to analytically see which adjustment is appropriate.


      (The best manner to understand these diagrams is to understand that the satellite arc makes a half circle and that the tracking movement of mount of dish makes another half circle and when these two half circles are aligned then dish is properly tracked.)

      If at any time a satellite signal quality can be improved by manually lifting or lowering the dish then your adjustments are not complete. A perfectly tracked C-band arc can appear to be 'all over the place' when you go to program the Ku satellites - do not be shocked. So repeat fine tuning steps on the Ku arc but stay away from further north/south adjustments in Ku fine tuning unless you are really convinced it will be beneficial or you can really get 'mucked up'!! Be sure, on Ku, that you are not chasing weak or half transponder channels and that your dish size relative to site location relative to transmitted footprint is conducive for high quality reception from the questionable weak signal, i.e. check the footprint of that transponder to see if it is being transmitted to your region.
      Ku signal strength can vary greatly from transponder to transponder within a satellite - especially on hybrid C/Ku satellites. On Ku, national news feeds are usually strong throughout the coverage region; regional feeds may be on a spot beam; local news feeds may be uplinked weakly and dependent on a very large dish at the home station to bring in a quality picture; private educational classes are often half transponder transmissions and depend on a very large dish at the receive site to bring in a quality picture. For dedicated Ku satellites the energy level of the transponders is more even and your major problems will be one of spot beams - you may be under a strong regional coverage yet be marginal in a spot coverage.
      If you really want to 'play' with your system further (and your wife does not mind), position and leave the dish on the satellite with weak channels and experiment with moving the focal point (the feed) in and out slightly then with moving the setting of the F/D ratio slightly. Remember that warped dishes (antenna symmetry), missing panels, hail damaged panels and loose bolts in the mount (especially check the bolt that connects the pivot axis tube to the mount cap) will deter top performance from your system - and Ku reception is the most sensitive to incorrect focal length and F/D settings.
      When you are satisfied with your efforts, recheck that all bolts are completely tight and definitely tighten the mount cap to axis tube bolt. Also, make a definitive mark on the pole/mount cap for the correct alignment just in case extremely high winds should cause the dish to rotate slightly on the pole. In high winds, position the dish at the top of the arc at which point is the least resistance to wind forces; aiming the dish into the wind will put the most strain on your installation.
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