TVRO Cables & Wiring
Webbed satellite cable is the most convenient way to connect big dish satellite TV receiving equipment
to the outside dish electronics. All the wires and coaxial cable necessary to receive
satellite television from a movable dish are included in the webbed cable. Most webbed
cables will have 4 wire bundles. Two of the bundles contain coaxial cable, the other two
wire bundles contain regular stranded wire.
Webbed satellite cable is direct burial cable. Direct burial cable is made to be buried
in soil. PVC pipe should not be used with direct burial cable. Underground PVC pipe will fill
up with water or condensation and cause the cable to rot. If you must use PVC pipe, be sure
to drill holes at regular intervals in order to allow for drainage.
The coaxial cable that is part of the webbed cable is the same basic
type used for cable TV and VCRs. Coaxial cable's function is to carry
high frequency signals. The regular stranded wires carry power and control
signals between the satellite receiving equipment in your home and the outside
dish electronics.
Webbed Satellite Cable Bundles
A typical webbed satellite TV cable will generally have four seperate wire bundles with a thin
jacket material that holds all four bundles together.
The two left cables on the diagram on the left are coaxial cables which carry the amplified
high frequency signals coming from the satellites in space. These cables are labeled with
a "C".
The single cable labeled "P" on the diagram on the left is the smallest wire bundle. This
bundle contains three small gauge stranded wires for the Polorotor.
The last wire bundle contains 2 large gauge stranded wires and at least 2 smaller gauge
wires. These wires are for the actuator motor that moves the satellite dish.
Satellite Receiving Equipment Connections
Coaxial cable is connected to the LNB on the dish feed and to the satellite
receiver via F connectors for standard RG6. Your particular satellite web cable may
have 1 or 2 coaxial cables. The 2nd cable can be used for a Ku-band LNB.
The LNB dramatically amplifies
the microwaves that are gathered and focussed by the dish. The LNB is powered
by 18 volts DC supplied from the satellite receiver. The 18 volts DC appears
between the coaxial cable's center conductor and shield.
The polorotor motor is located on the dish feed and is used to rotate the
small metal probe at the feed's center. When the satellite dish and feed
are properly aligned, the probe is located at the dish's focus. The probe's
proper position will depend on the polarity of the satellite transponder
(channel) being viewed. Polarity is termed as horizontal or vertical. Adjusting
the proper positioning of the probe is called adjusting the skew. The 3
small polorotor wires can be seen coming out of a small motor attached to the
feed. These 3 wires on the motor should be matched up with the same colors
on the satellite web cable, always attach red with red, white with white, and black
with black. On the satellite receiver red is 5 volts, black is ground and white is pulse.
The color and number of wires for the motor wire bundle can vary widely. Most TVRO
satellite systems will only need 2 large and 2 small wires. Usually the thick wires will
be red and black or red and white, but it doesn't matter. The small wires can be any
color and often there is a bare wire ground in the bundle. Remember, you don't have
to use all the wires! The two thick wires carry the power to the motor that drives the actuator
arm in and out. If you hook up the motor power wires and the dish is moving
the wrong way, just reverse the wires. As the motor turns, pulses are sent
along the two small wires and applied to a counting circuit in the receiver or dish positioner.
If your motor sensor wires have two wires, the order of the wires doesn't matter.
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