Tech Works CI Series - Page 24

10/29/2019 Tech Works CI-Series Systems Planning & Installation Manual Page 24 of 42
CI-MSI-22
The MSI-22 is a Microphone and Speaker Interface for our Collaborative Intercom family of products.
There can be two Microphones (One from the Microphone Input; one from the PA-BUSS Input using a PA-
MI-1)
Two Speaker outputs (One from the Speaker Output; one from the PA-BUSS output using a AS-1 or PA-
402)
PRE-AMP
NOTCH
FILTERS
TALK SW
ALWAYS
MICROPHONE
OR
LINE INPUT
ALC OUT
BUFFER
OPTO
RCVR
PA-BUSS
INPUT
PA-BUSS INPUT ALERT
PA-BUSS INPUT AUDIO
ALERT
AUDIO
OPTO
RCVR
BUFFER SUM
LOCAL ALC
PA-BUSS INPUT
MASTER INPUT
CI-BUSS “SLAVE”
OUTPUT
CI-BUSS “SLAVE”
AUDIO INPUT
SLAVE INPUT
BUFFER SUM
LOCAL ALC
PA-BUSS INPUT
SLAVE INPUT
CI-BUSS “MASTER”
AUDIO OUTPUT
CI-BUSS “MASTER”
INPUT AUDIO
MASTER INPUT
AUDIO
CI-BUSS ALERT
CI-BUSS ALERT
CI-BUSS ACTIVE
ALC
OR
SUM
LOCAL ALC
PA-BUSS INPUT
MASTER INPUT
SLAVE INPUT
“LISTEN
LEVEL”
DUCK
MUX
TALK SW
CI-BUSS ALERT
ALWAYS
CI-BUSS ALERT
TALK SW
PA-BUSS IN ALERT
SELECT
MUX
AMP
ALWAYS
AUDIO
ALERT
PA-BUSS
OUTPUT
PA-BUSS INPUT AUDIO
PA-BUSS IN ALERT
SUM
LOCAL ALC
PA-BUSS INPUT
MASTER INPUT
SLAVE INPUT
“LISTEN
LEVEL”
DUCK
MUX
TALK SW
CI-BUSS ALERT
SELECT
MUX
PWR-AMP
SPEAKER
OUTPUT
OR
ALWAYS
CI-BUSS ALERT
PA-BUSS OUTPUT AUDIO
OR
ALWAYS
CI-BUSS ALERT
PA-BUSS IN ALERT
Basic Microphone / Speaker Interface Block Diagram (Transformers not shown for clarity)
Each input can be routed to an output or all outputs by placing routing jumpers inside the unit as desired.
The CI-BUSS interface performs the same function for additional units. The Microphone is processed
with ALC to be of constant level and passed to other Units in both directions as selected.
The ALC has an indicator for the Threshold of Limiting.
This indicator also serves as a setup indicator for adjusting the Microphone level.