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[20 September 2017 ] INFO *** BISS dan Tandberg Key (real time update)

Cabling

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.

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.

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' end connector (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.
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.

 

Power Passing Splitter

 

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.

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.
 

In-Line/Distribution Amps
 

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).
 

Servo Connections
 

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 the motor. 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 polarity probe 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!!

 

Actuator Wiring
 

(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 using
diameter 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).
 

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 its shape (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.
 

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.

 

GROUND ROD/SURGE PROTECTION:

I personally do not usually fool with ground rods though everyone recommends it - homeowners insurance should cover your satellite equipment - and certainly 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 with heavy 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 to connect 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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