Codan MT-4E, Maintenance Manual

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MAINTENANCE GUIDE | MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS
Chapter 5: Codan Radio System Testing Page 34
Receiver Reference Oscillator Adjustment
Connect the IFR 2975 and Codan Radio as shown in Figure 5-18.
Figure 5-18: Receiver Reference Oscillator Testing
The reference oscillator test on the receiver requires a connection directly into the Synthesizer, which
uses an SMB connector. Disconnect the SMB cable from the LO output of the synthesizer and connect
the small SMB-SMB cable to the SMB jack that is mounted on the Synthesizer (beneath the RF
Preselector). The SMB-BNC adapter is required to connect this point to the ANT input on the IFR 2975
as shown in Figures 5-19 (VHF and UHF 400 MHz Receiver) and 5-20 (UHF 700 / 800 / 900 MHz
Receiver).
Figure 5-19: VHF and UHF 400 MHz Receiver Reference Oscillator Connection
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
Synthesizer L.O. output from Receiver
to ANT input on IFR 2975
Computer running RSS
USB from
Computer to 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
To ANT input
on IFR 2975
SMB-SMB
cable
LO output of
synthesizer