- D-CAB – Digital Cable
- D-Sat – Digital Satellite
- D2MAC – This is an encrypted
satellite signal sent in analogue which has the luminance & chrominance
parts of the video signal broadcast sequentially. Typically used by
broadcasters in Europe.
- DAB – Digital Audio Broadcasting
- dBi - The gain of the aerial in
accordance with an isotropic source. This really is normally 2.15dB greater
than the gain in accordance with what half-wave dipole is.
- dBm – dB power in relation to a 1
milliwatt standard
- dBw – dB power to 1 watt.
- DCT - The Discrete Cosine Transform
is a way of getting at the redundancy that's in television images to have the
ability to decrease the datarate. It is a fundamental part of the MPEG-2
compression process.
- Decibel - A decibel is really a
logarithmic energy ratio, abbreviated dB. Could also represent a current or voltage
ratio when the currents or power are measured across (or through) identical
impedance. Suffixes towards the abbreviation indicate references: dBi,
isotropic radiator dBic, isotropic radiator circular dBm, milliwatt dBW, watt.
- Declination Offset - The adjustment
position of the polar mount between your polar axis and also the plane of the
satellite dish accustomed to pointing at the geosynchronous arc. Increases from
zero with latitude from the equator.
- Demodulator - Equipment that's made
to extract the wanted information from an incoming signal.
- Depolarisation – The Turning of the
polarisation from a radio wave whilst it travels through the air.
- Deviation – The Total number that a
carrier frequency is moved by a modulating signal.
- Dielectric - Insulation materials
to split up the conductors of the coaxial cable or even the performing circuits
of the capacitor.
- Digibox – A name commonly used for
a digital receiver of either satellite of terrestrial TV signals.
- DigiTAG - Is Europes version of DTG
within the United kingdom, as being a consortium of tv stations and producers
focusing on common standards inside the DVB framework with the aim of achieving
a EU wide marketplace for receiver designs. Digitag works underneath the
auspices from the EBU.
- Diplexer - A frequency-conscious
device for mixing or splitting signals in various frequency bands. A diplexer
includes a lower insertion loss compared to equivalent splitter.
- Dipole – Generally an aerial
element which is half a wavelength in length that has interconnecting at the
centre point.
- Discriminator – An electrical
circuit that demodulates an FM signal.
- DiSEqC - Digital Satellite A
digital control signal for manipulating the DiSEqC compatible units from the satellite
dish through a coaxial cable, i.e. motor
units, switches.
- DMC – Digi Master Contract
- DMX – Digi Master X (High Gain)
- Downstream – Infomation travelling
from the Web to a PC.
- DSB – Double Side Band signals
rather than SSB – Single Side Band
- DSO – Digital Switchover. A
schedule for the switchover of the UKs’ Transmitters from analogue to digital.
- DTI – Department of Trade &
Industry.
- DTT – Digital Terrestrial TV which
is also known as Freeview, which is received through a wide band aerial.
- DTV – Digital TV.
- DVB – Digital Video Broadcasting. –
EU regulation for digital TV.
- DVB-S – Digital Video Broadcast –
Satellite.
- DVB-T – Digital Video Broadcast –
Terrestrial.
- DVB –T2 – Digital Video Broadcast
Transmission - platform 2, the HD broadcast platform for digital terrestrial TV
transmissions (i.e, Freeview) - presently not ‘backward-compatible’ using the
earlier DVB-T1 platform.
- DVD - Digital Versatile (initially
Video) Disk. Data storage medium used, among other activities, for disbursing
consumer video having a standard recording 4.7GBytes giving 140 mins at
typically around 3Mb/sec, however with an optimum capacity of 8Mb/sec.
