Anritsu MG3641A - Manual (Page 178)

SECTION 7 PERFORMANCE TEST
7-10
7.3.5 AM modulation factor and AM distortion
(1) Test specifications
• Range 0 to 100 %
• Accuracy with reference to
≥0.4 MHz, ≤ +7 dBm, AM ≤ 90 %,
Source=Int1 1 kHz, and in a 300 Hz to 3 kHz demodulation band:
± (5 % of set value +2 %)
• Distortion with reference to
≥ 0.4 MHz, ≤ +7 dBm, Source=Int1 1 kHz:
< –40 dB (AM=30 %)
< –30 dB (AM=90 %)
(2) Measuring instrument for test
• Modulation analyzer
• Distortion meter
(3) Setup
Fig. 7-5. AM modulation factor and AM Distortion Test
(4) Test procedure
STEP PROCEDURE
AM modulation factor
1. Set the MG3641A/MG3642A output level to +7 dBm.
2. Set the MG3641A/MG3642A frequency and modulation analyzer receive frequency to the
expected frequency.
3. Turn on the MG3641A/MG3642A AM, and set Source to Int1 1 kHz.
4. Set the MG3641A/MG3642A AM modulation factor.
5. Read the indicator of the modulation analyzer.
6. Change the MG3641A/MG3642A AM modulation factor and repeat the measurement.
AM distortion
7. Set the MG3641A/MG3642A AM modulation to 30 % and 90 %.
8. Measure the demodulation output of the modulation analyzer with the distortion meter.
MG3641A/MG3642A
RF
IN AF
OUT INPUT
Modulation analyzer Distortion meter
Demodulation
signal