Bosch LBB 1903/10 User Manual

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Bosch Security Systems | 2003-09 | 3922 988 92883en
Plena Mixer Amplifier | Installation and Operating Manual | 
en | 14
Microphone 1 input has a 5-pole DIN (for a 3 or 5-pole DIN microphone) and a 6.3-mm phone jack connector 
wired in parallel. Only when connecting a microphone with a priority contact on pin 4 and 5 of the 5-pole DIN 
connector (2), this input has priority over all inputs except the emergency input. This microphone input can be 
included with a voice controlled circuit (VOX) which will overrule all the other input signals. How to activate the 
VOX is described in §2.1.
4.3 Chime ON/OFF-switch
Figure 4.3
Depending on the position of the chime ON/OFF-switch (1), switching on microphone 1 will activate the chime. 
The default chime volume is -8 dB (40 V), which will be sufficient in most applications. The volume can be altered 
using the potentiometer VR401 on the main PCB of the unit (see §2.3).
Note
Only use one of the two connection possibilities of each microphone input.
Note
Only when connecting a 5-pole DIN microphone to the 5-pole DIN connector of microphone input 1 the 
chime can be activated.
External settings and connections
115V/2
30V
Appara
tus deliv
ered
conn
ected
for 230
V-
Rated
input
power
: 400VA
This
apparat
us mus
t be ea
rthed
Warnin
g
2
1
3
4
Mic/Lin
e
Mic/Lin
e
CD
L
R
Aux
Line O
ut 1V
Inc
Out
In
Tel/Eme
r.
0
0 2
Chime
4 .5
1- -3
Call/M
ix
24VDC
In
Call Only
Mix Onl
y
100V
0
70V
0
100/70V
0 100/7
0V 0
8
0
1