HP 8530A, Руководство по эксплуатации и программированию, Страница: 323 / 439

Controlling Multiple Sources
1/10 * ( FREQ + 1.000000000 GHz )
RECEIVER
1.000000000 GHz
(The RECEIVER is set to a CONST ANT FREQUENCY of 1 GHz.)
Why these settings are used. Here are the objectives of this measurement setup:
The nal LO frequency must mix with a 100 GHz RF signal to produce a 1 GHz IF . Therefore
the nal LO frequency must equal 99 or 101 GHz. F or the sake of this example 101 GHz is
used.
The LO frequency output by the LO source must be 1/10th of the required LO frequency .
This is because the 10th harmonic mixers will essentially multiply the LO frequency by 10 (by
picking the 10th harmonic).
The setup must allow the receiver/frequency converter combination to measure the 1 GHz IF
signal.
These design objectives are met as follows:
The formula for SOURCE 2 must be:
1/10 * (RF FREQ + 1.000000000 GHz)
This yields:
Source 2 = 1/10 * (100 GHz + 1 GHz)
Source 2 = 1/10 * 101 GHz
Source 2 = 10.1 GHz
When the mixer picks the 10th harmonic , it will be at 101 GHz. Therefore the IF will be
1 GHz.
The Receiver must tune the HP 8511 frequency converter to measure 1 GHz. Setting
RECEIVER to a constant frequency of 1 GHz does this .
Figure 17-10 shows how the multiple source menu will appear after these changes are made .
Figure 17-10.
Finished Multiple Source Conguration for Hypothetical Module
17-16 Using System Functions