Audio The electrical signal, analogue or digitally encoded representing what you hear. Americans spell Analogue as Analog.
AAC, HE-AAC, AAC+ Advanced Audio Codec, superior to MP3 digital Audio and MP2 Audio. Uses about 1/2 the space as MP2 audio.
AC3 Codec for Dolby Digital (Stereo or 5.1 channel). Designed for Cinema, DVDs and BD (BluRay disc). Also known as DD or Dolby Surround Sound.
ASO Analogue Switch Off. The Date and Time an Analogue Transmitter is turned off finally, only leaving Digital TV. Then the Digital transmissions can be increased in Power and in some areas in UK more channels or HD added.
CAM Conditional Access Module Used with a viewing card to decrypt (unlock) FTV or PayTV. On some receivers such as Sky Digital boxes, the CAM is not available for TVs or “generic” Receivers, but only built-in as part of the main design. The CAM has a slot for a credit card sized or SIM sized viewing card. If it’s an “embedded” CAM (which can be entirely in software), then there is only a Card Reading Slot. Official CAM usually only works for one Company (Canal+ etc), though there are some “multi-CAMs”. This is why some TVs and Boxes for mainland Europe may have multiple embedded CAM and card slots and multiple CI. Not needed for Saorview, Saorsat, Freeview or Freesat as they are FTA.
CI Common Interface A slot similar to a Laptop PCMCIA slot that a CAM can be inserted into.
CI+ A CI with added feature: A CI+ compliant device must also implement an MHEG-5 interactive TV engine to manage navigation of the user within an interactive TV application, using its device remote control.
Codec Coder / Decoder. A system for carrying sound or pictures (audio or video) as numbers, i.e. Digital files or transmissions. CD-Audio codec has no compression, MP3 uses different levels of compression, so takes less space, but as you compress you lose quality compared to CD Audio. MP2, MP3, AAC, AC3, MPEG1, MPEG2 and MPEG4 are Codecs. MHEG5 is not a Codec.
DD Dolby Digital Another name for AC3 Sound. It can be Stereo or Surround.
Digital Aerial Does not exist and never will. There are only Aerials. They differ only by TV band or group and are identical for Analogue or Digital Terrestrial at similar TV frequencies.
Digital Dividend The Spectrum to be freed and money made from closing down Analogue Television
Digital Text Any Broadcast Text system replacing Teletext, though Teletext is actually entirely digital and always has been.
Diseqc (Digital Satellite Equipment Control), pronounced “Die-Sec”, is a special communication protocol for use between a satellite receiver and a device such as a multi-dish switch or a dish motor. DiSEqC was developed by European satellite provider Eutelsat. It uses the LNB / IF coax cable to the dish for power and signalling to the switch. It and multiple LNBs or a motor are needed to receive more than one satellite on a TV or Receiver.
DSO Digital Switch Over. Process of adding Digital TV transmitters while analogue TV is still on the air.
DTT Digital Terrestrial Television is recieved in the same way as ordinary TV that uses an aerial. It needs a Digital Tuner built into the TV or sa separate box like Sky or UPC uses, except not compatible. A Cable TV or Satellite TV box does not work for DTT
DVB-C Digital TV modulated for Cable. Cable in Ireland has no free channels. It’s Pay TV only. It also carries Analogue TV and DOCSIS Broadband (Internet).
DVB-S Digital TV modulated for Satellite transmission. Satellites are about 36,000 km away. A Dish and LNB is required as well as the DVB-S digital tuner.
DVB-S2 A newer type of Satellite transmission. Most but not all HD channels use it. All HD Satellite receivers now can do DVB-S and DVB-S2, such as “Freesat HD” or “Sky HD” box. Some TVs can use it.
DVB-T Digital TV modulated for use with Aerials. Another name for DTT in Europe. USA/North America, Japan, China and South America use 4 other incompatible DTT systems. Be careful buying equipment on-line.
DVB-T2 A very new type of Terrestrial transmission, currently only in the UK since 2009 for HD DTT only. DVB-T2 receivers are all thus all HD and work with DVB-T also for HD or non-HD signals.
EPG Electronic Program Guide. Like having a live RTE-guide or Radio Times built in. May show five to seven days ahead of all channels with details on each program. A PVR (Personal Video Recorder) for Saorview or Saorsat can use the EPG to “tag” all the programs to be recorded. Much easier than programming a VHS.
Two versions of the EPG
The exact appearance of the program guide depends on the TV or Set-box used.
Freeview: UK FTA (Free to Air) digital TV via an Aerial, excluding HDTV. Various places can receive N.I., I.O.M. and Welsh Transmitters. Analogue is turned of in Wales, so people that used to get good Analogue TV now get better Digital. In N.I, there is still Analogue (turning off in 2012) and after ASO (Analogue Switch Off), Irish reception of Freeview will improve in Border areas. See the N.I. Digital Page. A Freeview TV or Set-box generally won’t work on Saorview, but a Saorview receiver will work with Freeview, if you live in an area with UK reception.
Freeview+: TVs or set-box with built in digital recording, excluding HDTV, a PVR for Freeview as VHS will be no use. Almost all will not work for Saorview.
Freeview HD: The HD version of Freeview. A “Freeview HD” IRD (TV or set-box) will receive Freeview and Saorview, if there is a signal. N.I. does not get HD till 2012, but some people in Ireland can receive the Freeview HD from I.O.M and Wales. A Soarview receiver will not receive Freeview HD, unless it has a DVB-T2 tuner internally.
Freeview+ HD: TVs or set-box with built in digital recording of terrestrial TV (via Aerial), a PVR for “Freeview HD” and “Freeview” as VHS will be no use. All models should work for Saorview also.
Freesat: UK FTA (Free to Air) digital TV, excluding HDTV, picked up on a Dish from a Satellite 36,000km above the Equator @28.2E. This has more channels than Freeview and can be received for free anywhere in Ireland. All the most viewed channels are actually on Sky. Pay Channels such as Sky Sport and Sky One are not on Freesat, but they have less than 2% viewing time, among Sky Subscribers. No Pay channel has more than 2% viewing time and most are less than 0.1%! No Freesat model will work with Saorsat.
Freesat+: TVs or set-box with built in digital recording via a dish, excluding HDTV, a PVR for Freeview as VHS will be no use. None will work for Saorsat.
Freesat HD: UK FTA (Free to Air) digital TV, including HDTV picked up on a Dish from a Satellite 36,000km above the Equator @28.2E. This has more channels than Freeview and can be received for free anywhere in Ireland. All the most viewed channels are actually on Sky. Pay Channels such as Sky Sport and Sky One are not on Freesat, but they have less than 2% viewing time, among Sky Subscribers. No Pay channel has more than 2% viewing time and most are less than 0.1%! Most but not all “Freesat HD” models will work with Saorsat. See the Satellite page on receiving Saorsat and Freesat/Freesat HD.
Freesat+ HD: TVs or set-box with built in digital recording via a dish, excluding HDTV, a PVR for Freeview as VHS will be no use. Most but not all “Freesat HD” models will work with Saorsat. See the Satellite page on receiving Saorsat and Freesat/Freesat HD.
FTA Free To Air: No encryption, no extra charges (you do have to pay a TV licence in Ireland and UK). You may freely receive the channel by any method for personal domestic use. Different rules apply to Hotels, Guest Houses, Community TV schemes and other redistribution. An Apartment Distribution system may freely distribute all channels as long as Pay TV channels are not decoded, it’s just aerial or dish sharing in this case.
FTC: Free To Carry: A Satellite, Cable, Terrestrial Broadcaster, Community TV, Hotel System or IPTV provider does not need to pay to carry the channel, only obtain permission from the Channel and from the Regulator. Most FTA channels are not FTC.
FTV, Free To View: Encrypted, so a viewing card or other method to unlick the picture is needed. No subscription in pay TV sense, but a once off or annual charge
HD Ready: Means the TV can somehow (maybe only via Component or HDMI) display all normal kinds of HDTV pictures though the TV is not “full” HD resolution. Typically WXGA PC resolution of 1366 x 768 pixels
iDTV Integrated Digital TV. Typically a TV with Terrestrial, Satellite or Cable (or a mix) “Digital” Tuner as well as an Analogue Tuner.
IRD Integrated Receiver Decoder. A TV or Setbox with Tuner for digital signals and MPEG2 or MPEG4 & MPEG2 video Decoder. Some can receive more than one kind of Digital Transmission, most only work for one kind of system.
LNB Low Noise Block Down-converter. Converts the Extremely high frequency (3,700MHz to 22,000MHz depending if C-Band, Ku-Band or Ka-Band Satellite) to a frequency band just above UHF TV, to feed to the rest of the Satellite Receiver via coax cable.
LNBF an LNB with a built in “feed horn” to focus or collect the signal from the dish better. Most Domestic LNB are actually LNBF.
HDMI (High-Definition Multimedia Interface) is a compact digital connection between High Definition Set-box or BluRay (BD) player and an HDTV. The traditional large SCART connector does not do HDTV.
HDMI socket on equipment
HDTV High Definition TV. Usually 1080 visible lines rather than normal 576 lines visible on 625 Line Analogue or SD Digital
hi-def see HDTV
MHEG5 Multimedia and Hypermedia Experts Group Version 5, a “middleware” system providing similar features to those familiar on a Sky SetBox for Program Guide (EPG), Interactive text with pictures and video. Unlike MPEG2 and MPEG4 this is not a codec and nothing to do with video decoding or compression.
MHP Multimedia Home Platform, DVB-MHP, used as alternative to MHEG5
Middleware Software added to a TV or Set-box to give more features than simply tuning in and changing channel. The most used are “OpenTV” (Sky), “MediaHiway” (UPC), MHP (Italy) and MHEG5 (UK). Only MHEG5 is royalty free.
MP2: Original Codec for Digital Audio on Digital TV and Radio.
MPEG2: Motion Picture Expert Group. The version of Codec used for Video on non-HD (SD) Freeview, Sky, UPC cable Digital and Freesat (excluding HD). Never used for HDTV.
MPEG3: There is no MPEG3. It was abandoned.
MPEG4: Motion Picture Expert Group. The version of Codec used for Video on “Freeview HD”, “Sky HD”, UPC cable Digital HDTV and “Freesat HD”. All HDTV requires MPEG4. Additionally many newer Digital services, including Ireland’s Saorview and Saorsat, only use MPEG4 for video, even SD (non-HD), with no use of MPEG2 at all. MPEG4 video of same quality and resolution takes about 1/2 the space or less, so twice the channels or more HDTV can be carried on same Transmitter or Satellite. Freeview, Sky and Freesat can’t change to MPEG4 to have more space as the original MPEG2 based TVs and Set-boxes can’t be upgraded to MPEG4. This is why on older services only the HDTV uses MPEG4 and new networks use only MPEG4.
MPEG5 There is no MPEG5 video codec at time of writing. People may say or write this meaning MHEG5. Which is “middleware software” nothing to do with MPEG codecs.
Multiswitch Used to distribute Satellite Dish signals for 8 to 2000 Satellite tuners. A PVR uses two connections.
Pixel: smallest dot or picture element of a digital image or Flat screen TV.
PVR: Personal Video Recorder. The replacement for VHS and DVD Recorders. They have a Digital Tuner and simply copy the live transmission exactly to a Computer type hard Drive (HDD). They can record from 50 hrs of assorted programs to an amazing one week of EVERY channel at once depending on Model and Capacity. Playback is thus identical quality to Live TV. They can “pause” Live TV if the phone rings, baby cries, door bell or pot boils over. When un-pausing some allow slightly faster than real-time playback so you can “catch up” with Live transmission. When you finish watching the channel/program the automatic background recording stops. Some models can “save” programs to DVDs or BD (blu-ray) writeable disc. The basic Analogue Tuner DVD recorder or VHS is obsolete. Typically you have a on-screen 7 day guide which allows you to pick a program or entire series for automatic recording. Some models will even automatically record if you normally watch a program and miss it without manually scheduling it.
Resolution: This has various meanings: (1) The number of pixels wide and high a screen has. (2) The Density of the pixels or Image dots. (3) The transmitted width and height in dots per line and visible lines. (4) The “optical resolution”, quoted in lines, but these lines can mean different things. 720 dots across can only resolve 360 separate actual lines. Broadcasting uses many more different resolutions than DVDs or BD (Blu Ray Disc)
Saorsat: Irish FTA Digital Satellite service, possibly on air from May 2011
Saorview: Irish FTA Digtial Terrestrial service, soft or Technical Launch 29th October 2010, Full Launch in may 2011
Set-Box: Formerly called a Set-top Box, first used in 1950s to add ITV to BBC only TV sets! Modern TVs are too skinny to have a box on top. Over the years these have added Teletext, Cable TV, MMDS, Analogue Satellite, Sky Pay TV Satellite, Freesat, Freeview and even Digital Recording on a Computer type Hard Drive (PVR) . Some TV sets have Satellite tuners or even “PVR” features built-in.
SCART: Traditional cable for VHS, DVD or Set-box to connect to a TV. Does not carry HDTV. RGB mode is the best quality.
SD, SDTV, Standard Definition: Standard Definition. 576 lines visible on 625 line PAL Analogue or on Digital TV in Europe. USA and Japan only use 480 visible lines on 525 Line NTSC Analog and Digital.
Sub Pixel: A mix of Red, Green and Blue pixels that the eye averages to give a coloured pixel. Also used is Red, Green, Blue, Green (may be brighter and just as good colour) and Red, Green, Yellow and Blue (less accurate, but more vivid colour). Triple LCOS, LCD, RP CRT and DLP projectors don’t have sub pixels. Windows on LCD screens can use “sub pixel” addressing to improve text quality, but if the resolution is too low you get coloured fringing.
Teletext: A text Broadcast system first deployed on Analogue TV in the 1970s, though Teletext is actually entirely digital and always has been. On Analogue it’s transmitted in unseen part of the picture. On Digital it gets a separate data stream as there is no “unseen” part in a Digitally encoded TV picture. A late 1970 version with photo images in the text, like modern digital text, was never adopted as transmission was too slow on Analogue TV.