172 Chapter 2
Performance Verification Tests
23. Frequency Response, Agilent E4402B and E4403B

23. Frequency Response, Agilent E4402B and

E4403B

This test measures the amplitude error of the analyzer as a function of
frequency. To measure frequencies of 100 kHz and greater, the output of
a source is fed through a power splitter to a power sensor and the
analyzer. A function generator is used as the source from 100 kHz to
10 MHz, and a synthesized sweeper at 10 MHz and greater. To measure
frequencies below 100 kHz, a DVM with a 50 Ω load replaces the power
sensor.
For improved amplitude accuracy the power splitter is characterized
using a “reference” sensor connected to one power splitter output port.
The other power splitter output port connects to the “buried” sensor; it
is not removed from the power splitter. Once the characterization is
done, the reference sensor is removed and replaced by the analyzer.
Measurements are made at the same frequencies used in the
characterization. The analyzer marker amplitude measurements are
corrected using the characterization data to determine the absolute
flatness error and the flatness error relative to 50 MHz.
This procedure does not test frequency response with the optional
preamplifier (Option 1DS) turned on. If the analyzer is equipped with
Option 1DS, also perform the “Frequency Response, Preamp On”
procedure. Analyzers with Option UKB are tested down to 100 Hz in dc
coupled mode. In ac coupled mode, Agilent E4402B analyzers are tested
down to 100 kHz.
The related adjustment for this performance test is “Frequency
Response.”
Equipment Required
Synthesized sweeper
Function generator
Power meter
RF power sensor (2 required)
RF Power splitter
Digital multimeter
Adapter, Type-N (m) to Type-N (m)
Adapter, Type-N (m) to BNC (f)
Dual banana plug to BNC (f)
BNC Tee (BNC f,m,f)
Cable, BNC, 122-cm (48-in) (2 required)
Cable, Type-N, 183-cm (72-in)
Termination, 50 Ω, BNC (m)