24
Appendix H: Viavi CX300 Tests
MAINTENANCE GUIDE | MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS
Transmitter CTCSS Testing
MT-4E Transmitters can be programmed, per channel, to generate CTCSS tones internally, or to allow for
External Input of the CTCSS tones from another device (such as a tone-remote adapter).
Connect the CX300 and Zetron Radio as shown in Figure H-24. The Tx Subtone input connection is only required
when testing the External Input. If the internal programming is used to generate the CTCSS tone, disconnect the
Tx Subtone input from the CX300.
Figure H-24: Transmitter CTCSS Testing
On the CX300, load Zetron preset 06 Tx CTCSS from your internal drive. Enter the correct RF frequency on the
CX300, set the MIC MODE switch on the front panel of the transmitter to Analog and flip the other switch to KEY
TX (or set the switch to NORM and key the transmitter through the RSS).
Computer running RSS
USB from
Computer to Rx
TRANSMITTER
BUS
CNTL
MIC
A D
RF OUT
OFF
NORM
KEY
DIGIT
ANALOG
AL
TX
MIC MODE
IN
REF
USB
FREQUENCY (MHz)
MADE IN CANADA
MODEL # CODE
VOL
SYSTEM REGULATOR
METER
+
-
MADE IN CANADA
ON
OFF
EXT
SPKR
INT
EXT
SPKR
OFF
POWER
ON
2
1
5
4
3
6
7
8
11
10
9
FUNCTION
12
Tx Subtone Input
)
)
2
3
B
(
d
n
u
o
r
G
d
n
a
2
2
B
s
n
i
p
o
t
(
o
t
(
Tx RF OUT to
RF DUPLEX on CX300
AF OUTPUT
