User`s guide

2-25
Making Mixer Measurements (Option 089 Only)
High Dynamic Range Swept RF/IF Conversion Loss
4. Set the analyzers LO frequency to match the frequency of the LO source by pressing:
5. To select the converter type and low-side LO measurement configuration, press:
In this low-side LO, down converter measurement, the analyzer's source frequency
range will be offset higher than the receiver frequency range. The source frequency
range can be determined from the following equation:
receiver frequency range (100 – 1000 MHz) + LO frequency (1500 MHz) = 1.6 − 2.5 GHz
6. To view the conversion loss in the best vertical resolution, press:
Figure 2-21 shows the conversion loss of this low-side LO mixer with output filtering.
Notice that the dynamic range from the pass band to the noise floor is well above the
dynamic range limit of the R Channel. If the mixer under test also contained
amplification, then this dynamic range would have been even greater due to the
conversion gain of the mixer.
Figure 2-21 Example of Swept IF Conversion Loss Measurement
System
INSTRUMENT MODE
FREQ OFFS MENU
LO FREQUENCY
1500
M/µ
RETURN
DOWN CONVERTER
RF > LO
FREQ OFFS ON
VIEW MEASURE
Scale Ref
AUTOSCALE