TN600-6 AC-3E Audio Card.indd

TECHNICAL NOTES
MT-3/4 Radio Systems
TN600 AC-3E Audio Control Card
The AC-3E audio control card is a plug-in module which provides audio routing, PTT routing, and muting control for
MT-3 and MT-4 radio systems. The audio control card includes the following features:
• jumper selectable audio routing, PTT, and muting.
• two independently adjustable hang timers adjustable from 50 milliseconds to 10 seconds.
• sockets for optional CTCSS decoders and encoders.
• low power analog and CMOS control circuitry.
• maximum standby current of 30 mA.
• true balanced 600  inputs and outputs for external equipment connection.
• optically isolated inputs and outputs for control by external equipment.
• suitable for Type 2 E&M signalling.
FREQUENCY (MHz)
REF
IN
7
5
NORM
OFF
KEY TX
ANALOG
DIGITAL
7
FREQUENCY (MHz)
FREQUENCY (MHz)
MICMODE
RECEIVER
FREQUENCY (MHz)
SQ . DI SA B L E
TX
SQ. DISABLE
N O RM
OFF
FUNCTION
2
10
3
4
8
5
7
CNTL
BUS
USB
9
RX B
MIC
TX B13
5
RF I N
RF OUT
REFERENCE
RF OUT
REFERENCE
RF IN
CNTL
BUS
9
INPUT
6
+
INPUT
POWER
ON
METER
-
MIC
5
13
TX A
1
11
VOL
REF
IN
5
SYSTEM REGULATOR
12
9
NORM
OFF
KEY TX
NORM
OFF
USB
TX B
TRANSMITTER
A D
A D
TX A
RX A
RECEIVER
FREQUENCY (MHz)
TRANSMITTER
AUDIO
CONTROL
OFF
ON
OFF
SPKR
INT
EXT
EXT
SPKR
PULL DOWN
TO REMOVE
MADE IN CANADA
MADE IN CANADA
MADE IN CANADA
MADE IN CANADA
MODEL # CODE
MODEL # CODE
MODEL # CODE
MODEL # CODE
MADE IN CANADA
The AC-3E audio control card is fully configurable and can be used for all repeater and base station applications.
The audio control card module circuitry consists of three main functional blocks:
AUDIO
CONTROL
7
5
7
5
(1) The repeater control circuit, which allows all COR / PTT routing combinations for all repeaters.
(2) Optional CTCSS modules that can be installed at the factory or in the field.
TX A
RX A
TX B
5
13
TX A
RX B
9
TX B13
5
(3) Audio routing circuitry for active level control and distribution of receiver to transmitter audio
signals. The AC-3E is designed for applications where interface to external equipment is required.
All audio and control inputs/outputs are isolated by transformers and opto-isolators on the AC-3E.
9
PULL DOWN
TO REMOVE
600 , -25 dBm to 0 dBm adjustable
600 , -20 dBm to +3 dBm adjustable
4.7 K, -25 dBm to +3 dBm adjustable
External Audio Input:
External Audio Output:
Internal Audio Input:
The AC-3E audio control card includes four potentiometers on the front panel for adjusting internal audio levels.
Optional frequency select rotary switches can also be mounted on the front panel of the audio control cards, giving
easy access to 16 pre-programmed receiver and transmitter operating frequencies. Two switches are mounted on
the front of the audio control cards that can be configured to control CTCSS on / off or repeat disable. Configuration
of all switches on the audio control card is set up at the factory at the time of order.
43 Erie Street
Victoria, B.C.
Canada V8V 1P8
TN600 Rev 6-0-0
Toll Free Canada & U.S.A.
Phone: 1-800-664-4066
Fax:
1-877-750-0004
May 14
International
Phone: 250-382-8268
Fax:
250-382-6139
© 2014 Codan Limited All rights reserved.
Internet
Email: LMRsales@codanradio.com
Web:
www.codanradio.com
Page 1 of 2
TECHNICAL NOTES
MT-3/4 Radio Systems
TN600 AC-3E Audio Control Card
Although the Audio Control Card can be configured to work in various configurations with add-in options and
functionality, the three main functions of the AC-3E Audio Control Card are shown in Figures 1, 2 and 3:
CORA -> PTTA
JUMPER
CORA
INHIBIT
PTTA
INHIBIT
OPTIONAL
CTCSS
ENCODER
TXA
PTT
RXA
COR
CORA -> PTTB
JUMPER
CORB -> PTTA
JUMPER
CORB
INHIBIT
RXB
COR
CORB -> PTTB
JUMPER
RXA
DISCRIMINATOR
O/P
REPEATER
INTER
CONNECTIONS
RXA
BALANCED
O/P
TXA
SUBTONE
I/P
CTCSS
DECODER
RXA
MUTE
Jumper
Selection
Jumper
Selection
TO AUDIO ROUTING
PTTB
INHIBIT
TXB
PTT
HANG
TIMER
A
OPTIONAL
CTCSS
ENCODER
OPTO
ISOLATORS
HANG
TIMER
B
AUX1
COR
RXB
DISCRIMINATOR
O/P
AUX2
COR
RXB
BALANCED
O/P
AUX1
PTT
TXB
SUBTONE
I/P
CTCSS
DECODER
RXB
MUTE
Jumper
Selection
Jumper
Selection
TO AUDIO ROUTING
AUX2
PTT
AUXILIARY CONNECTIONS
Figure 1: Repeater Control
Figure 2: CTCSS Control
AUDIO
GATE
AUDIO
LEVEL
CONTROL
C19
AUX1 BALANCED
I/P
R120
RECEIVER A
AUDIO
GATES
C20
AUDIO
LEVEL
CONTROLS
TXA AUDIO
TXA BALANCED
I/P
R5
DISTRIBUTION
AMPLIFIER
TXB AUDIO
RXA BALANCED O/P
FROM CTCSS CONTROL
TXB BALANCED
I/P
R9
AUXILIARY AUDIO
R13
AUX1 BALANCED
O/P
LINE
DRIVER
AMPLIFIERS
AUDIO
GATE
RECEIVER B
B11
A11
AUDIO
LEVEL
CONTROL
R48
B14
DISTRIBUTION
AMPLIFIER
AUX2 BALANCED
I/P
R123
RXB BALANCED O/P
FROM CTCSS CONTROL
A14
R52
AUXILIARY AUDIO
R56
LINE
DRIVER
AMPLIFIERS
C1
AUX2 BALANCED
O/P
C3
Figure 3: Audio Routing
43 Erie Street
Victoria, B.C.
Canada V8V 1P8
Page 2 of 2
Toll Free Canada & U.S.A.
Phone: 1-800-664-4066
Fax:
1-877-750-0004
International
Phone: 250-382-8268
Fax:
250-382-6139
© 2014 Codan Limited All rights reserved.
Internet
Email: LMRsales@codanradio.com
Web:
www.codanradio.com
TN600 Rev 6-0-0
May 14
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