Operating instructions

LOCAL OPERATION
3-50 46882-311D
Dx test (duplex testing)
C3376
➤ ➤
POWER
METER
MOD
METER
RF
COUNTER
AF
COUNTER
TONES
GEN
RF
GEN.
MOD
GEN
1
MOD
GEN
2
'N'
ANTENNA AF
IN
AF
OUT
BNC
RF
OUT
RF IN
IN/OUTRF
AF
OUT
AF
IN
20dB
ATTEN.
AF
FILTERS
DIST-
ORTION
METER
AF
VOLT-
METER
TRANSCEIVER UNDER TEST
SERVICE
MONITOR
Fig. 3-12 One port duplex test setup
Overview
With the Dx TEST mode selected, the screen and menu shown in fold out diagram (4 -0) is
displayed.
The Dx TEST mode is provided so that transmitter and receiver functions of transceiver operation
can be studied simultaneously.
‘One port’ and ‘Two port’ transceivers can be tested. See Fig. 3-12, One port duplex test setup,
and Fig. 3-13, Alternative two port duplex setups.
The Dx TEST mode display does not give all the information that is available from the individual
Tx TEST mode and Rx TEST mode displays but these displays are available individually by
selecting the appropriate test mode.
When interchanging between the Tx TEST mode, Rx TEST mode or Dx TEST mode, any active
transmitter test and any active receiver test will remain functional.
There are two exceptions to this.
The first is with the modulation generators used for receiver tests and the audio generators used
as a modulation source for transmitter tests. The two AF generators in the monitor serve both
functions. Therefore, although both can be assigned to either function, if modulation is required
on receiver and transmitter simultaneously, only single tones are possible.
The second exception is that the distortion measuring functions can be made only on the AF
signal taken from the receiver under test and fed into the AF input connector of the monitor.
The output from the Tx TEST mode demodulator is fed to the AF amplifier as in Tx test mode.
However, as the AF measuring circuits are continually switching functions when in Dx TEST
mode, the output from the loudspeaker or headset is discontinuous.