Bosch Appliances 3922 988 43318 manual CCU Audio Routing Modes, MIX-MINUS mode FIG, DCN System a

Digital Congress Network Installation and Operating Manual Chapter 4 - Central Control Equipment en 4-12

4.9CCU Audio Routing Modes

To provide additional functionality in the CCU, the DCN software from release version 7.01 includes two new ‘Audio Routing’ modes - ‘MIX-MINUS’ and ‘INSERTION’ mode. Both modes are selected by setting DIP-switches (S9) on the TCB4 card located in the Central Control Unit CCU (see Chapter 4.5.2).

MIX-MINUS mode (FIG 4-8)

The main feature of this mode, is that audio signals connected to the ‘Line-Input’ of the CCU are no longer routed to the ‘Line-Output’ of the CCU.This feature is especially desired for the following applications:

1. Where a remote audio connection is made via a telephone coupler for connection to a remote

delegate or specialist speaker.

Installation:

To set the CCU for the Mix-Minus mode Dip-switch ‘S9’ on the Trunk Communication Board must be set as follows:

DIP-switch S9			(See Chapter 4.5.2 (Table 4-4:)
Switch-2	Switch-3	Mode
Off	Off	Standard
On	Off	Mix-Minus

DCN System A DCN System B

2. To interconnect two DCN systems.

IMPORTANT!: In the ‘Mix Minus’ mode, a permanent audio channel is used for ‘Line-Input’. Therefore the number of available interpretation channels is one channel less than in the standard mode (i.e. 10 channels instead of 11 channels as available in ‘Stand-alone’ and ‘Multi-CCU’ systems.

NOTE: For recording the total audio signal (i.e. Floor + Line-Input) use an Audio Media Interface unit LBB 3508/00 on channel 0 (see Chapter 4.11).

Using this mode of operation, the audio connection is considerably improved, and avoids ‘Echo’ due to feedback as was experienced in the standard mode of operation.

FIG 4-8gives an example of ‘Audio Routing’ in the CCU’s and the external routing for connection of two DCN systems A and B.

NOTE: If connection is done via the Public Telephone Network, telephone couplers must be used (not shown in FIG 4-8).

		Mix-Minus	Mix-Minus
		Insertion OUT	Insertion IN
	∑	CH.14	CH.14	∑
		Line-OUT	Line-OUT
		Mix-Minus	Mix-Minus
	∑	Insertion IN	Insertion IN	∑
		Line-IN	Line-IN
CH.0
Master volume
PC control
CH.12

CCU Volume

CH.13

Delegate/Chairman microphones

Interpreter headphones

CH.0 Unit loudspeaker Delegate headphones

Master volume

PC control

CH.12	Equalizer PA
	Local PA (MCCU)
CCU Volume
CH.13	Delegate unit
	loudspeaker

FIG 4-8 ‘MIX-MINUS’ mode

Bosch Security Systems 04-2003 3922 988 43318 en CCU Audio Routing Modes