SERIES 560-9XXXX AND 5400-6XXXX SWR AUTOTESTERS
OPERATION AND MAINTENANCE MANUAL
1.
INTRODUCTION
This manual provides product descriptions and
specifications for WILTRON Series 560-9XXXX and
5400-6XXXX SWR Autotesters (Figure 1). It also
includes Performance Verification procedures for
these components.
2.
GENERAL DESCRIPTION
WILTRON SWR Autotesters are precision-balanced
Wheatstone bridges that contain an internal preci-
sion reference termination in one arm of the bridge.
Series 5400-6XXXX models have N or BNC type test
port connectors. Models 560-97XXX have N or
GPC-7 type test port connectors, and models
560-98XXX have WSMA or K type test port connec-
tors (see Table 1 on page 2).
These units are broadband microwave measurement
components that are used with the Model 562 Scalar
Network Analyzer and with Series 54XXX Scalar
Measurement Systems for making fixed-frequency
and swept-frequency return loss (SWR) measure-
ments. Return loss measurements are used over a
wide range of radio and microwave frequencies to
check the performance of systems, subsystems, and
microwave components such as amplifiers, direc-
tional couplers, attenuators, filters, splitters, and
terminations.
3.
PERFORMANCE SPECIFICATIONS
Performance specifications for the SWR Autotesters
are listed in Table 1 (page 2).
4.
EXPLANATION OF SWR
AUTOTESTER SPECIFICATIONS
Certain key specification terms are explained below.
a. Accuracy.
This three-element term defines
the accuracy with which an SWR Autotester can
make a reflected signal measurement. The three
elements (0.01
±
0.06
ρ
2
) are described below.
1st Element: (0.01) is the directivity of the SWR
Autotester expressed as a reflection coefficient
(40 dB for this example, refer to Table 3 on
page 9).
2nd and 3rd Elements:
±
0.06
ρ
2
is the deprecia-
tion in accuracy due to test port mismatch (im-
pedance discontinuity). Element 2 (0.06) is the
inherent test port mismatch expressed as a re-
flection coefficient. The 3rd element, rho (
ρ
), is
the reflection coefficient of the device under test
(DUT). The entire expression describes the
measurement uncertainty caused by the re-
flected signal being re-reflected by the test port
mismatch.
b. Directivity. A figure of merit expressed in dB.
This figure represents the ratio of the power
levels as seen at the output port when (1) the
test port signal is fully reflected, and (2) the test
port is perfectly terminated.
c.
Frequency Sensitivity. The maximum varia-
tion in output power/voltage that can be ex-
pected due to a change in frequency over the
specified range when the input power is held
constant
d. Output Time Constant. The amount of time
required for the selected output pulse to either
rise from the 10% to the 90% point or fall from
the 90% to the 10% point on the waveform.
490 JARVIS DRIVE
●
MORGAN HILL, CA 95037-2809
P/N: 10100-00028
REVISION : B
PRINTED: NOVEMBER 1994
COPYRIGHT 1992 WILTRON CO.
Figure 1. Typical Series 560-9XXXX