Specifications

Chapter 6 43
Making Distortion Measurements
Third-Order Intermodulation Distortion
Making Distortion Measurements
Step 3. Set the analyzer center frequency and span:
Press
Preset, Factory Preset (if present).
Press
FREQUENCY Channel, Center Freq, 300.5, MHz.
Press
SPAN X Scale, Span, 5, MHz.
Step 4. Reduce the RBW until the distortion products are visible:
Press
BW/Avg, Res BW, ↓.
Step 5. Set the mixer level to improve dynamic range:
(ESA) Press
AMPLITUDE Y Scale, More, Max Mixer Lvl, –30, dBm.
(PSA) Press
AMPLITUDE Y Scale, More, More, Max Mixer Lvl, –30, dBm.
The analyzer automatically sets the attenuation so that a signal at the
reference level has a maximum value of
−30 dBm at the input mixer.
Step 6. Move the signal to the reference level:
Press
Peak Search, Mkr →, Mkr → Ref Lvl.
Step 7. Reduce the RBW until the distortion products are visible:
Press
BW/Avg, Res BW, ↓.
Step 8. Activate the second marker and place it on the peak of the distortion
product (beside the test signal) using the
Next Peak key.
Press
Marker, Delta, Peak Search, Next Peak.
Step 9. Measure the other distortion product:
Press
Marker, Normal, Peak Search, Next Peak.
Step 10. Measure the difference between this test signal and the second
distortion product (see Figure 6-4):
Press
Delta, Peak Search, Next Peak.
Figure 6-4 Measuring the Distortion Product