User`s guide

Table Of Contents
220 Agilent E5505A User’s Guide
7
Residual Measurement Fundamentals
Procedure
1
Connect circuit as per Figure 155 and tighten all connections.
2
Offset the carrier frequency of one synthesizer to produce a beatnote for
cal.
3
After the phase noise system reads the beatnote, set the software to the
same carrier frequency.
4
Adjust the phase difference at the phase detector to 90 degrees
(quadrature) either by adjusting the synthesizer or by adjusting an optional
variable phase shifter or line stretcher. Quadrature is achieved when the
meter on the front panel of the phase noise interface is set to zero.
Measured beatnote/automatic calibration
This calibration option requires the reference source to be a PSG (E8257D,
E8267D, or E8663D) which has the functionality to adjust the phase remotely.
Advantages
Simple method of calibration.
Eliminates the need for a line stretcher or phase shifter.
Disadvantages
Requires the reference source to be a PSG-D.
Procedure
1
Connect the equipment as shown in Figure 156.
2
The reference source must be either an E8257D, E8267D, or E8663D.
Figure 155 Synthesized residual measurement using beatnote cal