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Chapter 6
Performing Tests and Measurements
AM Transmitter Testing
22130634
CX300 ComXpert Operation Manual
Rev. 001
February, 2022
6 - 13
7.
RF Receiver
Reference Level
: set to 27 dBm. Select to AGC to auto.
8.
RF Receiver
IF Bandwidth
: select 6.25 kHz.
9.
Navigate to the
Analog Mod
controls and settings.
10. Demod Type
: select
AM
.
11. Mod Level Type
: select
Live
.
12. Mod Level Measurement
: select
(Pk-Pk)/2
.
13. Psophometric Filter
:
None
.
14. High Pass Filter
: select
300 Hz
.
15. Low Pass Filter
: select
5 kHz
.
In this example, the CX300 AF Generator uses the following settings:
To Configure the CX300 AF Function Generator:
1.
Navigate to the
AF Generator
controls and settings.
2.
AF Generator 1
Shape
: select
Sine
.
3.
AF Generator 1
Frequency
: set to 1 kHz (test modulation frequency).
4.
AF Generator 1
Level
: set to 0.2 V.
5. AF Gen 1 Enable
: set to OFF.
6. AF Gen 2 Enable
: set to OFF.
7. AF Gen 3 Enable
: set to OFF.
8.
Navigate to the Audio In controls and settings.
9. Coupling
: select
DC
.
NOTE - Use of External Attenuator
The expected transmit power of the UUT is 50 Watts (47 dBm) which is the maximum
input power of the CX300, so an external attenuator is required for this test.
The UUT transmits at 47 dBm through the 10 dB external attenuator, reducing the
amplitude received by the CX300 to 37 dBm (5 W), therefore the Reference Level of
the CX300 is set to 37 dBm so that the power measurements factor in external
attenuation to reflect the actual power generated by the UUT.
NOTE - IF Bandwidth Selection
For this test, the UUT will generate AM using a 1 kHz tone, which is a narrow-band
signal, so the IF Bandwidth is set to the narrowest setting of 6.25 kHz.