HP 8712C, User Manual, Page: 89 / 559

Making Measurements
Measuring Conversion loss
700
MHz
Filter
2 0 0
7 0 0 9 0 0
1100
MHz
M H z
M H z
( R F - L O ) ( R F )
2 0 0
MHz
Figure Filtering Out the Unwanted Mixing Product
Inserting a 700 MHz filter in the measurement setup removes the
unwanted signals at 200 MHz, 900 MHz and 1100 MHz, providing an accurate
measurement of the desired IF signal at 700 MHz.
In the following example, the conversion loss of a mixer will be measured
with RF input frequencies over a 15 MHz span centered at 900 MHz. With an
LO frequency of 200 MHz, the mixer IF frequency will sweep over a 15 MHz
span centered at 700 MHz.
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