Codan MT-4E, Maintenance Manual

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MAINTENANCE GUIDE | MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS
Chapter 6: Additional Radio System Tests Page 58
RADIO SYSTEM TESTING THROUGH FILTERING
EQUIPMENT
The Transmitter RF power output and Receiver sensitivity tests can be performed by injecting and
measuring the RF signals through the fi ltering equipment. Connect the test set to the antenna port of
the fi ltering equipment as shown in Figure 6-1. When testing through this equipment, the test results
will be noticeably lower as the fi ltering equipment typically has 1 to 3 dB of insertion loss associated
with it.
Figure 6-1: Transmitter and Receiver Testing Through Filtering Equipment
TRANSMITTER
CNTL
BUS
MIC RF OUT
A D
ANALOG
DIGITAL
NORM
OFF
KEY TX
MIC MODE
REF
IN
USB
FREQUENCY (MHz)
MADE IN CANADA
MODEL # CODE
RECEIVER
NORM
SQ. DISABLE
OFF
CNTL
BUS
A D
RF N I
REF
IN
USB
FREQUENCY (MHz)
MADE IN CANADA
MODEL # CODE
VOL
SYSTEM REGULATOR
METER
+
-
MADE IN CANADA
ON
OFF
SPKR
INT
EXT
EXT
SPKR
OFF
POWER
ON
2
1
5
4
3
6 7
8
11
10
9
FUNCTION
12
REPEATER
CONTROL
RX B
TX B
RX A
TX A
PULL DOWN
TO REMOVE
9
5
3
7 11
15
9
13
3
7 11
15
SWITCH A SWITCH B
Rx Balanced Audio Output
(from pins B26 and Z26)
T/R port from IFR 2975 to
Antenna port on Duplexer
HELP MODE
TAB
SHIFT
+
-
.
BKSP
HOLD
RETURN
ESC ENTER POWER
1 2
ABC
3
DEF
JKL MNO GHI
6 5 4
TUV WXYZ PQRS
9 8 7
# 0 *
VOLUME
SQUELCH
GEN T/R ANT
125 W MAX
MIC AUDIO I/O DVM CH2 CH1 SCOPE TEST PORT
100V MAX 100V MAX 100V MAX
AUDIO IN AUDIO OUT 1 AUDIO OUT 2
Audio In
RF OUT from Tx
to Duplexer
Duplexer to
RF IN on Rx