Bosch Appliances Webcam 3922 988 43318 User Manual

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Bosch Security Systems
 
 | 04-2003 | 3922 988 43318 en
 
Digital Congress Network
 
 | Installation  and Operating Manual | Chapter 1 - Introduction to DCN
 
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 | 1-3
Installation equipment.
 
1.6   Installation equipment.
 
Fast cost-saving installation is an important benefit of the DCN’s digital technology. A thin twin-coaxial 
cable carries all the system’s digital signals, eliminating the need for the costly and vulnerable multi-
core cables used in conventional analogue installations. The same cable is used to transport the signals 
to all delegates’ microphone units throughout the system and can be ‘tapped off ’ at any desired point 
to connect the microphone units or any system unit associated with the DCN system. Later capacity 
extensions - for example to add extra microphone units does not demand changes to the system 
cabling. All that is needed is to connect the required DCN system units or branches to the installed 
cabling. Trunk-line splitters and extension cable assemblies are available to simplify installations in 
difficult working areas.
 
DCN’s System Philosophy.
 
The DCN introduces the latest digital technology, bringing far reaching benefits to the audio quality, as 
well as to promote the addition of a wide range of external peripheral equipment to conference 
systems.
shows the concept of DCN’s digital communication techniques. The Network cabling forms 
the system infrastructure providing the communication media between the Microprocessor 
controlled Central Control and all units connected to it. Using standard plugs and connectors 
throughout the system means that units can be connected to the Network at any convenient points, 
making installation quick and simple.
Communication through the Network cabling and all units connected to it, is done using three 
dedicated digital communication IC’s, ACN 
 
1
 
, ACN 2 and ACN 3. Units that include an ACN 
 
1
 
 
microprocessor - such as the delegate unit, chairman unit and interpreter desk - communicate to the 
Central Control Unit, via the units ACN 2 microprocessor on a send and receive basis (active or 
passive). Units that include an ACN 3 microprocessor - such as the Channel selector units - receive 
information on a receive basis only, such units are known as passive units.
 
Praedic
 
The integrated circuit (IC), PRAEDIC (Professional Audio Encoder Decoder Integrated Circuit) 
combines a built-in amplifier with both Analogue-to-Digital and Digital-to-Analogue convertors. The 
IC converts analogue signals (such as from a delegates’ microphone) and digitizes them for 
distribution throughout the DCN network cabling. In return the digitize signal is then fed back to the 
Praedic and converted back to an analogue signal for distribution throughout the DCN units - such as 
delegate loudspeakers and headphones.
 
FIG 1-1   DCN’s digital communication technique
Alternative for PC
with LBB 3510/00
Network card
DCN Discussion
Delegate/Chairman/Interpreter 
(contribution & distribution)
Channel selector unit
(language distribution)
ACN 1 - up/down
ACN 2 - up/down
ACN 3 - down only
Central Control Unit (CCU)
Delegate/Chairman unit (Concentus)
ACN 1
ACN 1
ACN 3
ACN 1
ACN 1
ACN 3
DAC
PRAEDIC
PC-bus
PRAEDIC
ACN 1
PRAEDIC
ACN 2
PERSONAL
COMPUTER
DAC
LBB 3510/00 
Network card
LBB 3512/00 
Data Distribution Board
CONTROL
PANEL
µProc.
e.g Hall Display
PRAEDIC
µProc.
FLASH
EPROM
RAM
DSP
Netw
or
k cab
ling