Agilent Technologies 8510C Operating And Programming Manual page 162

Controlling Multiple Sources
Many measurement systems require remote mixers, and therefore require an LO source. Such
a system is shown in Figure 5-5. The network analyzer controls all aspects of RF and LO
source frequencies. In setups that use multiple sources, the Multiple Source Menu allows the
network analyzer to properly manage these frequencies.
Here is an example of a setup that requires multiple source mode. The system shown uses an
LO source and 3rd harmonic mixers.
This setup creates two management tasks for the network analyzer:
The LO source must supply the appropriate LO signal to the mixer. The mixer uses the
third harmonic of the LO signal. The network analyzer must compensate by setting the LO
source frequency to be 1/3 of the needed frequency. The formula shown in Figure 5-7 would
be appropriate for this situation.
The mixer must produce a 20 MHz IF for the network analyzer. Therefore, the third
harmonic of the LO frequency must be 20 MHz away from the RF frequency.
The Multiple Source Menu provides the special control for this and other types of setups.
SYSTEM
4
Press
shown in Figure 5-6.
www.valuetronics.com
Figure 5-5. Actual LO Frequency Required by a Harmonic Mixer
NNNNNNNNNNNNNN NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
MORE EDIT MULT. SRC.
5
to display the Multiple Source Menu. It appears as
Using System Functions
Controlling Multiple Sources
5-11