HP 8530A, Operating And Programming Manual, Page: 318 / 439

Controlling Multiple Sources
Controlling Multiple Sources
Many measurement systems require remote mixers , and therefore require an LO source . Such
a system is shown in Figure 17-5. The receiver controls all aspects of RF and LO source
frequencies . In setups that use multiple sources , the Multiple Source Menu allows the receiver
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 .
Figure 17-5. A ctual LO Frequency Required by a Harmonic Mixer
This setup creates two management tasks for the receiver:
The LO source must supply the appropriate LO signal to the mixer . The mixer will use the
third harmonic of the LO signal. The receiver must compensate by setting the LO source
frequency to be 1/3 of the needed frequency . The formula shown in Figure 17-7 would be
appropriate for this situation.
The mixer must produce a 20 MHz IF for the receiver . 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 .
Press 4 SYSTEM 5
NNNNNNNNNNNNNN
MORE
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
EDIT MULT. SRC. to display the Multiple Source Menu. It will appear as
shown in Figure 17-6.
Using System Functions 17-11