Agilent Technologies 8719D, User Manual

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Filtering is required in both and broadband measurements, but you can implement it more
easily in the situation. Therefore, when configuring broad-band (swept) measurements,
you may need to trade some measurement bandwidth for the ability to more selectively
signals entering
the
analyzer’s receiver.
Frequency Selection
By choosing test frequencies (frequency list mode), you can reduce the effect of spurious
responses on measurements by avoiding frequencies that produce IF signal path distortion.
LO Accuracy Stability
The analyzer source is phaselocked to its receiver through a reference loop. In the frequency
offset mode, the mixer under test is inserted in this loop. To ensure that the analyzer
phaselocks correctly, it is important that you use an source that has frequency accuracy
better than MHz and residual FM 20 RMS.
Up-Conversion and Down-Conversion
determines which direction the internal source must sweep in order to achieve the requested
IF frequency. For example, to measure the lower sideband of a mixer, where the RF signal
is below the (RF the internal source must sweep backwards, See the examples in
Figure 6-90.
o f U p c o n v e r t e r
o f D o w n c o n v e r t e r w i t h
o f U p c o n v e r t e r w i t h
E x a m p l e o f
Figure 6-90. Examples
of Up Converters and Down Converters