Installation and Maintenance Manual
As a Remote Microphone and Message Playback
See Figure 7. This installation uses a 300MB interface with a 300VSC-1 or 300SCW-1. The CommCenter
acts as a remote microphone audio input and adds message playback capability to a SelecTone system.
Adjust the gain on the 300MB so that the audio output is at the required audio input level for the remote
microphone input (16 mVrms max.) on the 300VSC-1 and the 300SCW-1. Failure to adjust the gain causes
distortion and clipping in the system.
MODEL 300VCS-1
4 5
TB1
SIGNAL LINES
TWISTED PAIR
Driving a 25 Vrms Speaker Line
See Figure 8. In this installation the CommCenter is directly driving one or more speakers. The total
power consumed must not exceed the drive capability of the CommCenter.
GROUND
120/240 Vac
10
TB2
14
Figure 7 Model 300MB with remote microphone and message playback
GROUND
120/240 Vac
GAIN
10
1
17 16
CNTR
TB2
120 VCA
17
1
7
12 13 14
16
TB2
SHIELDED
Figure 8 Model 300MB with 25 Vrms connections
MODEL 300MB
GAIN
1
17
14 13
CNTR
TB1
Model 300MB-SD CommCenter Series D1
MODEL 300MB
10
8
1
TB1
MODEL 300GC
SIGNAL LINES
SHIELDED
TWISTED PAIR
1
CONNECTIONS TO 300MC
300MB
300VSC-1/300SCW-1
TB1-8
PTT-NO
TB2-13
TB1-10
PTT-COM
TB2-7
TB1-16
SIG COM
TB2-14
TB1-17
MIC OUT
TB2-12
MODEL AM25CK
POWER
120 Vac
120 Vac
LOCAL
LOCAL
POWER
POWER
TB1-13
TB1-14
TO ADDITIONAL SPEAKERS,
40 OHMS MAXIMUM LOAD
PTT
GND
MIC COM
MIC AUDIO IN
LINES
120 Vac
290A7517
-
SIGNAL
+
SIGNAL
290A7333