Xoro HSD 7790, Operation Manual

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HSD 7790
45
Engl
ish
GLOSSARY
5.1
5.1-multichannel encoding means, that 5 audio channels with full frequency response are present
(left, center, right, surround left, surround right) plus a subwoofer channel (represented by the „.1”)
providing deep humming frequencies you are used to know from modern cinemas. Both Dolby Digi-
tal
®
(including AC3) and DTS
®
support 5.1-coding and –decoding.
Aspect ratio: 4:3 and 16:9
Full Frame refers to programs developed for TV display with an aspect ratio of 4:3. Widescreen re-
fers to programs developed for screens with an aspect ratio of 16:9.
If a widescreen program is displayed on a 4:3 screen, the picture will have black borders on top and
bottom.
CD
A CD (Compact Disc) is a metal-coated plastic disc. It has a diameter of 12 cm and a thickness of
about 1,2 mm. It was developed by Sony and Philips in 1985. The advantages are digital storage of
music enabling very natural sound reproduction. Beyond this, the data is stored more compact, the
handling is easy. The long lifetime of the media and the fact that usage does not decrease quality
made the CD the ideal storage media.
In the meantime, 12 different storage media have been developed from the first CD. The mostly
used are CD-DA (Compact Disc - Digital Audio) , CD-ROM (Compact Disc - Read Only Memory),
and the DVD (Digital Versatile Disc). One can store about 74 to 80 minutes of music on a CD (-DA).
This is equal to 650 to 700 MB.
Signal transmission is performed touchless with a laser beam. The CD is being read from the middle
to the outer side. The data or music is recorded in a spiral from the middle to the outer side.
A CD has pits and lands, the distance is about 1,6 mm. The laser light created by a laser diode
passes different mirrors and prisms and then is focused by a lens to a laser beam. This laser beam
scans the data spiral of the CD. On the pits, the laser beam is reflected in another direction and is
detected by a photocell. The photocell transmits the signal to a microprocessor, which converts the
digital data to an audio signal. The rest is done by the sound system.
Contrast
Means the range of luminance between the brightest and the darkest pixel, which can be displayed.
DVD
The DVD (Digital Versatile Disk) was introduced in 1995 and is a storage media with a large capac-
ity.
While a standard CD can store 650 MB of data, the DVD can store up to 9 GB. Especially when it
comes to video playback, a large storage capacity is important. Beyond its high capacity, the con-
sumer enjoys high quality video and audio. A DVD can store up to 8 different audio streams, so in
best case, the movie can be watched in 8 different languages.
DVB MPEG-2
DVB is the abbreviation of Digital Video Broadcasting, which is a standardization group. DVB-T is
one type of DVB mode (T=Terrestrial). MPEG is the abbreviation of Motion Picture Experts Group, a
working group which defines international standards for audio and video digital compression. The
MPEG-2 standards are mainly applied in digital TV signals.
FEC
FEC stands for Forward Error Correction, applied to correct signal transmission errors between an-
tennas and the receiver.