Codan MT-4E, Maintenance Manual

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MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS | MAINTENANCE GUIDE
Chapter 5: Codan Radio System Testing Page 23
RECEIVER TESTING
Receiver Analog Testing
Connect the IFR 2975 and Codan Radio as shown in Figure 5-3:
Figure 5-3: Receiver Analog Testing
On the IFR 2975, recall Codan setup 1 (Rx_Ana) from your internal drive. Enter the correct RF frequency
and ensure that the deviation level of the 1.0 KHz tone is set correctly for your receiver (wide / narrow).
Enter the correct CTCSS tone (if used) and deviation level for the tone. On the Codan Radio system,
ensure the receiver is turned on and turn the System Regulator Speaker switch to ON and INT. Set the
FUNCTION rotary switch to position 3 for Rx A or position 5 for Rx B (depending on the receiver being
tested), then turn the volume up until the 1 KHz tone is audible.
In the Jumper Settings area of the Service section on the RSS, ensure that the “Subtones on audio
path” selection is set to “Don’t pass” as shown in Figure 5-4. The IFR 2975 will conduct all tests with
CTCSS tones on the audio, giving erroneous measurements, if the Subtones are set to “Pass”.
Figure 5-4: RSS Subtone Settings
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
RECEIVER
NORM
SQ. DISABLE
OFF
CNTL
BUS
A D
RF N I
REF
IN
USB
FREQUENCY (MHz)
MADE IN CANADA
MODEL # CODE
Rx Balanced Audio Output
(from pins B26 and Z26)
Computer running RSS
USB from
Computer to Rx
T/R port from IFR 2975 to RF IN on Rx
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