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Dictionary
In the following text will terms that are used
mostly referring to satellite TV explained.
If You think that something here is wrong or You have addition
to this dictionary please send an email.
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A
ACTUATOR
The running and returning system for controlling motorized antennas.
ADC
Analog-to-Digital Conversion - Process of converting analog signals
to a digital representation. DAC represents the reverse translation.
AM
Amplitude Modulation---The baseband signal is caused to vary the
amplitude or height of the carrier wave to create the desired
information content.
AMPLIFIER
A device used to boost the strength of an electronic signal.
ANALOG
A form of transmitting information characterized by continuously
variable quantities, as opposed to digital transmission, which
is characterized by discrete bits of information in numerical
steps. An analog signal is responsive to changes in light, sound,
heat and pressure.
ANIK
The Canadian domestic satellite system that transmits Canadian
Broadcasting Corporation's (CSC) network feeds throughout the
country. This system also carries long distance voice and data
services throughout Canada as well as some transborder service
to the U.S. and Mexico.
ANNTENA
Device that is used to send and receive signals that are passed
on to the receiver.
APERTURE
A cross sectional area of the antenna which is exposed to the
satellite signal.
APEX
Highest point. (i.e. on a motorized antenna the highest point
in the satellite belt).
APOGEE
The point in an elliptical satellite orbit which is farthest from
the surface of the earth. Geosynchronous satellites which maintain
circular orbits around the earth are first launched into highly
elliptical orbits with apogees of 22,237 miles. When the communication
satellite reaches the appropriate apogee, a rocket motor is fired
to place the satellite into its permanent circular orbit of 22,237
miles.
ARC
Satellite belt. A imaginary line that has the shape of half of
a circuit and connects all satellites in the Clark’s belt.
ASPECT RATIO
The expected TV ratio. Standard TV has a ratio of 4:3, but widescreen
TV uses a 16:9 ratio.
ASTRA DIGITAL RADIO
System for digital emitting of audio programs by using compressed
signals. It is emitted on sound transponders and you need a special
digital receiver to receive it.
ATTENUATION
The loss in power of electromagnetic signals between transmission
and reception points.
ATTITUDE CONTROL
The orientation of the satellite in relationship to the earth
and the sun.
AUDIO SUBCARRIER
The carrier between 5 MHz and 8 MHz containing audio (or voice)
information inside of a video carrier.
AUTOMATIC FREQUENCY CONTROL (AFC)
A circuit which automatically controls the frequency of a signal.
AUTOMATIC GAIN CONTROL (AGC)
A circuit which automatically controls the gain of an amplifier
so that the output signal level is virtually constant for varying
input signal levels.
AV
Any equipment for video and audio.
AZ-EL MOUNT
Antenna mount that requires two separate adjustments to move from
one satellite to another.
AZIMUTH
The ankle between the satellite and the geographic south (given
by the compass) is expressed in degrees and can west or east,
i.e. Astra 19.2°E.
B
BACKHOUL
A terrestrial communications channel linking an earth station
to a local switching network or population center.
BACKOFF
The process of reducing the input and output power levels of a
traveling wave tube to obtain more linear operation.
BAND PASS FILTER
An active or passive circuit which allows signals within the desired
frequency band to pass through but impedes signals outside this
pass band from getting through.
BANDWITH
The frequency width on which a signal is broadcasted or which
allows devices to receive signals. It can be 18, 27, 36 or 72
MHz.
BASEBAND
This is the satellite TV signal from the receiver, which has yet
not been transformed into a useful TV signal.
BAUD
The rate of data transmission based on the number of signal elements
or symbols transmitted per second. Today most digital signals
are characterized in bits per second.
BEACON
Low-power carrier transmitted by a satellite which supplies the
controlling engineers on the ground with a means of monitoring
telemetry data, tracking the satellite, or conducting propagation
experiments. This tracking beacon is usually a horn or omni antenna.
BEAM
Signal transmission via satellite. The satellites signal beam
emitted from the satellite to the earth. There are wide beams-
covers a big area, narrow beam- covers a smaller area, pot beam-
covers only a specific area.
BEAMWITH
The expected ankle of the satellite antenna.
BELLING-LEE CONNECTION
A connection that is used to connect TV antennas to the TV, receiver
and video. In prior times it was used on the satellite receiver
line in.
BER Bit Error Rate
The precision of a digital signal. Similar to the analogue S/N
ratio.
BIRD
Bird is a word that is often used referring to satellites.
BIT RATE
The speed of digital transmission. Usually it is expressed in
Mb/s. the higher the bit rate the better is the picture and sound
since there are more data sent. I.e: 5Mb/s is approximately PAL
quality and 2.5Mb/s is VHS quality.
BLANKING
An ordinary television signal consists of 30 separate still pictures
or frames sent every second. They occur so rapidly, the human
eye blurs them together to form an illusion of moving pictures.
This is the basis for television and motion picture systems. The
blanking interval is that portion of the television signal which
occurs after one picture frame is sent and before the next one
is transmitted. During this period of time special data signals
can be sent which will not be picked up on an ordinary television
receiver.
BLOCK DOWN CONVERTER
A device used to convert the 3.7 to 4.2 KHz signal down to UHF
or lower frequencies (1 GHz and lower).
B-MAC
A method of transmitting and scrambling television signals. In
such transmissions MAC (Multiplexed Analog Component) signals
are time-multiplexed with a digital burst containing digitized
sound, video synchronizing, authorization, and information.
BORESIGHT
The side of the antenna that is turned towards the antenna.
BUISINESS TELEVISION
Corporate communications tool involving video transmissions of
information via satellite. Common uses of business television
are for meetings, product introductions and training.
C
CAM
Conditional access module- systems that are used to decode encoded
satellite programs.
CARRIER
The basic radio, television, or telephony center of frequency
transmit signal. The carrier in an analog signal. is modulated
by manipulating its amplitude (making it louder or softer) or
its frequency (shifting it up or down) in relation to the incoming
signal. Satellite carriers operating in the analog mode are usually
frequency modulated.
CARRIER FREQUENCY
The main frequency on which a voice, data, or video signal is
sent. Microwave and satellite communications transmitters operate
in the band from 1 to 14 GHz (a GHz is one billion cycles per
second).
CASSEGRAIN
A sort of parabolic satellite antenna that uses a convex hyperbolic
secondary reflector.
C-band
Area of frequencies from 3.700-4.200 GHz that is used for satellite
signal transmission, mostly in use in the USA.
CENTRE-FEED DISH
A satellite antenna with the focus in the centre.
CHROMINANCE
Part of the signals that carries the data for colour.
CI
Common Interface- the standard connection to connect additional
equipment on the receiver. Mostly used by CAM’s. Basically it
is the same system as the PCMCIA system used by computers and
notebooks.
CIRCULAR POLARIZATION
Unlike many domestic satellites which utilize vertical or horizontal
polarization, the international Intelsat satellites transmit their
signals in a rotating corkscrew-like pattern as they are down-linked
to earth. On some satellites, both right-hand rotating and left-hand
rotating signals can be transmitted simultaneously on the same
frequency; thereby doubling the capacity of the satellite to carry
communications channels.
CLARKE BELT
Look geostationary orbit.
C/N (carrier to noise ratio)
An antenna performance measure. Refers to the ratio between received
power and noise power. Is expressed in dB.
Co-Ax
Coaxial cables and connectors that are used for satellite and
antenna equipment.
CO-LOCATED
Satellite that have the same positions (i.e. Astra and HotBird).
Usually the distance between satellites is 0.2°.
COMPOSITE VIDEO
TV signal that contains data about colour, luminescence and synchro
data. Used in scart-connectors.
COMPRESSED DIGITAL TV
TV signal that is digitised and compressed, because repeating
signals are left out. It enables to send more programs via one
transponder.
CONAX
A coding system for Scandinavian digital programs developed by
Telenor.
CO-ROTOR
A device that unifies a feedhorn, depolarisator and a polarisator.
Usually used in C-band LNB’s.
CRYPTOWORKS
A digital program coding system.
D
DBS BAND
Part of the Ku band 11.700-12.500 GHz that is used for direct
transmission of satellite programs.
DECLINATION
The small ankle between the polarmount and the antenna that enables
it to receive all satellites in the satellite belt.
DECODER
Device that enables you to watch encoded programs.
DE-EMPHASIS
A filter that is used with another one (pre-emphasis that is there
when signals are sent) to decrease the rustling.
DEMODULATOR
This is a receiver part and it has the function of dividing audio
from video signals in the incoming signal.
DEPOLARISER
Device that enables the changing of circuit polarisation into
linear polarisation.
DIGITAL SATELLITE RADIO
System for digital radio program emitting, which uses 16 uncompressed
stereo stations on one transponder.
DIGITAL TV
See compressed TV.
DiSEqC
Digital Satellite Equipment Control- it is a system that is made
to control satellite equipment digitally. It is developed by Eutelsat
for watching Astra and Hotbrid with one antenna by using universal
LNB’s. the system is used to control peripheral equipment like
LNB’s, rotors and switches with a digitised 22kHz signal from
the satellite receiver.
DISH
Parabolic antenna that collects satellite signals.
D-MAC/D2-MAC
Two subversions of the Mac system.
DOWNLINK
The way from the satellite top the antenna.
DTH (Direct to Home)
Satellite TV for reception at home.
DUAL-FEED
Reception of two satellite’s signals by using one antenna on which
are placed two LNB’s.
DVB (Digital Video Broadcast)
European TV standard for digital program emitting. It is used
everywhere except for the USA.
E
ECM (Electronic counter measures)
Electronic counter measures are signals that are sent via satellite
to disable pirate cards.
EIRP (Effective Isotropic Radiated Power)
This is the measure of the power of satellite signals that is
emitted to the earth.
El-Az (Eleveation-Azimuth) Mount
A simple fixed antenna that allows you to adjust it in horizontal
and vertical directions.
ELEVATION
The ankle between the direction of received signals and the horizontal.
ENCRYPTION
The encoding of signals. You can’t receive encoded signals and
use them if you don’t have the decoder. Also called scrambling.
ENCHANTED
Converter (9.750 GHz oscillator) or receiver that can receive
signals in the frequency width of 10.700-10.950 GHz.
EPG
Electronic program guide- an on-screen graphical program view
for digital satellite programs. The EPG is sent by the program
itself and the receiver just displays it. If it is not sent the
receiver display no Information or no EPG.
EUROCRYPT
A coding system used for programs emitted in the D-MAC and D2MAC
system.
EVENT TIMER
A timer that is placed in the receiver. It enables the receiver
to turn itself on or off when you are not at home so you can record
programs.
EXTENDED IF
The frequency width of the receiver that allows you to receive
all frequencies that receives a universal converter. Usually 950-2050MHz
or 700-2150 MHz.
F
F-CONNECTOR
A connector used to connect converter and receivers.
FEC (Forward Error Correction)
Signals that are added to the main signal so that they can correct
errors that may appear during emissions.
FEEDHORN
Signal collector. Collects signals into the focus of an antenna
and send them to the LNB
FLAT-PLATE ANTENA
A flat, usually quadratic antenna that collect satellite signals
on its surface and sends them to the LNB
FLYING FEED LNB
A satellite antenna that has a LNB that is placed on motor, which
allows to move it lef and right so you can receive signals from
more satellites.
FOCAL POINT
Area in front of the antenna where signals of the focus antenna
are collected.
FOOTPRINT
Areas on earth where signals from one satellite can be received.
Includes the power of the received signal.
FREE TO AIR (FTA)
Emitting satellite program without encoding them.
FSS (fixed satellite services) BAND
A part of the frequencies 10.700-11.700GHz that are in commercial
use, but today they are mostly used for analogue programs.
G
GEOSTATIONARY ORBIT
The orbit used by TV satellites at a height of 36.000km. at this
height satellite move with the same speed as the earth does, so
this satellites are always visible on the same spot.
GEOSYNCHRONUOS ORBIT
See geostationary orbit
GHz
Gigahertz. 1 000MHz. One billion vibrations in one second.
GREGORIAN DISH
A subversion of satellite antenna that uses a concave hyperbolic
reflector that points signals to the converter and that is placed
opposite of the main reflector.
H
HALF-TRANSPONDER MODE
This is a method of sending two programs on one transponder by
dividing the bandwidth. It decreases the EIRP for about 4dB. Therefore
you need an antenna with a bigger scope.
HORISON TO HORISON
Device for the turning of antennas. It contains a motor and enables
the antenna to receive all satellites in a belt of 180°.
HORN
A satellite antenna that uses a bigger feedhorn and no reflector.
HDTV (high definition Television)
A future TV system that has more lines that build the visible
picture with more quality. PAL uses 625 lines and HDTV uses 1250
lines.
I
IF (intermediate frequency)
The signal in the cable between the receiver and the LNB. It’s
also the reception frequency of a receiver. By standard it is
950-1750MHz.
IF SHIFTER
Devices that is inserted into the LNB cable. It enables the LNB
to receive frequencies it normally couldn’t.
INCLINED ORBIT
The movement of satellites above and bellow the ARC. Satellites
that are placed in this orbit usually have already come to their
ends. To receive their signals a polarmount antenna is needed.
INCLINOMETER
Device for measuring of vertical ankles.
INTERFERENCE
Disturbances in sound and picture caused by unwanted signals.
IRD (integrated Receiver Decoder)
Device that unifies a satellite receiver and a decoder.
IRDETO
A coding system used for digital programs by German, Italian,
Greek and Arabic programs.
J
J17
It’s an audio de-emphasis system, which is used on some programs.
It gives you a cleaner sound.
JACK
See actuator.
K
KHz
Kilohertz. 1000 vibrations in one second.
Ku-Band
Frequency width from 10.700-18.000Ghz that is used for satellite
transmissions.
L
LADITUDE
Expressed in degrees. Refers to the geographical width. Distance
south or north from the equator.
LOCAL OSCILATOR
Device ina LNB that receives satellite signals and transforms
them into frequencies that can be used by the receiver. Mostly
used are 10.000GHz for FSS ban, 9.750GHz for enhanced FSS band,
10.750 for DBS band, 11.475 GHz for telecom satellites, 10.600
GHz for the upper band of a universal LNB and 5.150Ghz for C band.
LONGITUDE
Distance to east or west from the 0th meridian. Geographical length.
LOOPTHROUGH
Pairs of incoming and exiting connections on a receiver that enable
adding other equipment into the TV signal.
LNB (Low noise block)
LNB, converter. Device that receives and enhances incoming satellite
signals and then transforms them into electric signals of a lower
frequency so that they can be used by a receiver.
LUMINANCE
Part f the TV signal that carries information about the luminance
of the picture.
M
MAC (Multiplexed Analogue Components)
Divided transmission of analogue components. This system was especially
developed for satellite TV. It is replaced by the digital standard
MPEG 2!
MAGNETIC POLARISER
A polarisation chooser that is controlled by the receiver’s power.
MARCONI TYPE LNB
Device that unifies LNB and polariser. Polarisations are chosen
by using voltages of 13V and 18V. Most of today’s LNB’s are of
this kind.
MCPC (Multi Channel Per Carrier)
Most digital programs are transmitted so that there send more
programs on one transponder. All these programs have the same
frequency but they differ in video and audio by their PID.
MECHANICAL POLARISER
It’s servo polariser that is controlled by electric impulses from
the receiver.
MEDIAGUARD
Coding system for digital programs that is used by the Canal Plus
Group and some other stations.
MHz
Megahertz. 1.000.000 vibrations in a second. Equal to 1000 KHz.
MICROWAVE
Electromagnetic waves at frequencies from 1-30 GHz.
MODULATOR
This device forces TV picture and sound on a radio carrier for
ground emitting or on a looprthrough.
MOUNT
It is the carrier of an antenna. It is used for the installation
and stabilisation of an antenna.
MPEG (Moving Pictures Experts Group)
International group for achieving standards in digital TV. MPEG
1 – picture quality of VHS and CD-Video, MPEG 2- picture quality
useful for satellite transmission.
MULTIFEED
An unmovable satellite antenna that has two or more LNB and is
therefore enable dto receive signals from more satellites.
N
NAGRAVISION
A coding system that is used for analogue and digital programs.
NOISE
Unwanted signal in a wanted one.
NOISE FIGURE
This is the rustling that a LNB adds to a signal. It expresses
the quality of LNB and is written in dB, i.e. 0.7 dB. The lower
it is the better the LNB. Today we have LNB’s with a noise figure
of 0.4dB.
NTSC (National Television Standards Committee)
System of television transmission mostly used in USA and Japan.
On a Pal receiver there will be no viewable picture at all or
there will be a b/w picture with many disturbances. In jokes this
system is called Never The Same Colour.
NVOD (Near Video On Demand)
Emitting programs, mostly movies, with a time delay of mostly
15 minutes to half an hour, so you can always watch the movie
with only little waiting times.
O
OFFSET
Type of satellite antennas with the focus somewhat bellow the
centre.
OMT (orthogonal mode transducer)
Device, which enables two LNB’s to receive horizontal and vertical
polarisations at the same time.
ORBIT
The orbit of a satellite around the world.
P
PAL (Phas Alternate Line)
TV system that is used for ground and TV emission in most parts
of the world.
PANDA 1
Noise reduction system that is used for audio signals and was
developed by Wegener Corp.
PARENTAL LOCK
Encoding of programs or menus to prevent uncontrolled watching
or adjusting. A security number of 4 digits is used.
PHONO
Connectors that are mostly used for audio, video and baseband.
PIN
Personal Identification Number- this number serves the purpose
to give the users of original satellite cards access to information
about their subscription, ordering of PPV programs and sometimes
some menus on the receiver.
POLARISER
Devices that is put in front of LNB and serves the purpose to
divide vertical and horizontal polarisations.
POLARMOUNT
Device that is used to turn the antenna. This movement allows
to watch more satellites and to receive every satellite in the
band.
POSITIONER
Device used to control the motor that is connected to a satellite
antenna and makes it possible to choose positions of where to
stop the antenna. This can be a separated device but it can be
also a part of a receiver.
POWERVU
Coding system for digital programs.
PPV (Pay per View)
This system enables you to watch exclusive emissions, but you
have to order them and pay for them. Mostly it’s abut movies or
sport events.
PRIMARY FOCUS
Subversion of satellite antennas that have the focus and the feedhorn
in front of them antennas centre.
PRO LOGIC (Dolby)
System for recording and reproduction of sound, which is developed
by Dolby Laboratories Corp. It is used to give you the sound reproduction
of a cinema at home.
R
RECEIVER
This device receives signals from a LNB and transform them into
signals that can be seen on a TV set in form of a picture and
sound.
REFLECTOR
A shape of an antenna-reflector that collects signals.
S
SECA
Societe Europeenne de Controle d`Access – SECA. System for encoding
of digital programs. This system is mostly used by the Canal Plus
Group.
SECAM (Sequence a memoire)
TV system that is used in some countries like in example France.
On Pal TV’s the picture of this system will be display black and
white.
SKEW
Fine tuning of polarisation that has the different ankles of incoming
signals from different satellites in mind.
SCART
Scart connectors are a European norm for connectors that uses
21 pin. Each pin transmits different signals.
SECONDARY FOCUS
A secondary focus receives signals from another satellite. This
is used on dual and multi feed antennas.
SLOT
The position of satellites in the Clark’s belt which is described
in degrees east or west from the south (0°)
SMART CARD
This is a plastic card the size of a credit card. It contains
the electronic key ro decode encoded programs. It is used with
according decoder.
SMATV (Satellite Master Antenna Television)
Satellite system for buildings and neighbourhoods, which use one
antenna and the programs are distributed via existing antenna
cables.
S/N (signal to noise) ratio
The ration between signal power and noise power. Expressed in
dB.
SNG (satellite news gathering)
Sending of materials via movable uplink stations.
SOFT SCRAMBLING
Decoding method that uses no subscriber card, but only a decoder.
SOUND IN SYNC
Type of emitting where information about sound a put into the
synchro impulses of the TV picture. Without the according decoder
this picture is instable and has no sound.
SCPC (single channel per carrier)
Some digital programs send information via special frequencies
on a transponder and they are independent from all other signals.
SPARCLES
Picture disturbances in form of little black and white sparks,
caused by weak signals or by using antennas of a smaller scope
than it is recommended.
STATISTICAL MULTIPLEXING
Compression technique that enables to put more programs on one
transponder.
SUBCARRIER
Auxiliary signal that is combined with the TV signal and is used
for sound and radio transmission.
S-VIDEO
Video format that uses independent emitting of luminescence and
chrominescence information.
SYNC
Signal that synchronizes the TV picture with the emitted picture.
If they aren’t the same the picture will be shaky.
SYSTER
Coding system that is used for analogue programs.
T
TELECOM BAND
Part of the frequency width of the Ku band 12.500-12.750 GHz.
First used by the French satellites telecom. Also called BBS (broadcast
satellite services) band.
TRESHOLD
Minimal C/N that is need for a picture without disturbances. Refers
to the sensitivity os a satellite receiver expressed in dB. The
lower the better.
TRESHOLD EXTENSION
Method used to lower the existing treshold of a receiver.
TRANSCODER
Device that is used to translate one TV standard into another
one (i.e. PAL into NTSC)
TRANSPONDER (transmitter-responder)
Device in the satellite itself. It’s used to receive signals from
earth and to reemit them to earth.
TRIPLE BAND LNB
LNB that is enabled to receive signals from FSS, DBS and Telecom
band in two areas that are chosen by changing the voltage sent
by the receiver (13 or 18V).
22kHz SWITCH
his switch uses a 22kHz sound signal to switch between the upper
and lower band on a universal receiver and to control other equipment,
i.e. DiSEqC switches.
U
UHF (ultra high frequency)
Signal that uses frequencies from 300-890MHz and is used to emit
ground programs.
UNIVERSAL LNB
This LNB uses two local oscillators and has two frequency bands:
10.700-11.700GHz, lo.9.750 GHz and 11.800-12.750GHz l.o.10.600GHz.
to switch between them a 22kHz sound signal is used.
UPLINK
The way of the signal from the station on earth to the satellite.
V
VIACCESS
Coding system used for digital emitting
VIDEOCRYPT
Coding system that was first used by BSkyB and is today no longer
in use.
VIDEOGUARD
Coding system for digital programs that is used by Sky Digital
and lately some others too
VOD (video on demand)
Programs are emitted directly after they were order in this emitting
system.
VOLTAGE SWITCHED LNB
Combined LNB with a polariser, which is mostly used on Astra systems
where the polarisations are chosen by using 13 an 18V voltages
send by the receiver.
W
WAVEGUIDE
Precisely made channel for microwave signals
WEGENER
See Panda1
WIDESCREEN
TV programs and receiver that do not use the conventional ratio
4:3 but they use the cinema ratio 16:9 or sometimes 14:9 and 21:9
WIDEBAND
Large frequency width for satellite receivers that is usually
700-2150MHz.
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