Agilent Technologies 8719D User Manual page 392

Compatible Instrument Modes and Sweep Types. Frequency offset is compatible with all
sweep types in the network analyzer mode.
Receiver and Source Requirements. Refer to Chapter 7, "Specifications and Measurement
Uncertainties. n
IF Input: R always; and port 1 or port 2 for a ratio measurement.
Display hmotations. The analyzer shows the annotation of s when the frequency offset mode
is on. The annotation of? indicates that the source frequency is approximately 10 MHz away
from the sum of the IF and Lo frequencies that you requested. This is most likely caused by
the Lo frequency being outside the - 1 to + 5 MHz accuracy requirement.
Error Message. If you connect your test device before you switch on the frequency offset
function, the error message PHASE LOCK CAL FAILED appears on the screen. This is normal, and
Spurious Signal P&s&and Frequencies. Unwanted mixing products (or spurious Lo signals)
at specific frequencies can cause measurement inaccuracy, because of the characteristics of
a sampler. These specific frequencies can be calculated. You can reduce unwanted mixing
products going to sampler by inserting a low pass fllter at your test device's IF output.
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