Agilent Technologies E4448A Service Guide

Chapter 4 97
Troubleshooting the RF Section (E4446A, E4447A, E4448A)
RF Section Description (E4446A, E4447A, E4448A)
Improper displayed signal amplitudes in some attenuator settings can
be isolated to either A13 or A14 based on which steps are incorrect.
Signal out of the attenuators can be measured by disconnecting the
appropriate semirigid cable and using a spectrum analyzer. Referring
to Figure 4-4, A14 has two 2 dB sections and one 6dB section. A15 has a
10 dB, a 20 dB and a 30 dB section. Verify that the attenuators are
receiving the correct switching sequences by using the following tables.
Table 4-1 A15 Settings
Attenuation
(dB)
30 dB
Select J4
pin 9
30 dB
Bypass J4
pin 4
10 dB
Select J4
pin 2
10 dB
Bypass J4
pin 1
20 dB
Select J4
pin 8
20 dB
Bypass J4
pin 5
0 High Low High Low High Low
10 High Low Low High High Low
20 High Low High Low Low High
30 Low High High Low High Low
40 Low High Low High High Low
50 Low High High Low Low High
60 Low High Low High Low High
70 Low High Low High Low High
Table 4-2 A14 Settings
Attenuation
(dB)
2 dB - B
Select
J3 pin 9
2 dB - B
Bypass
J3 pin 4
2 dB - A
Select
J3 pin 8
2 dB - A
Bypass
J3 pin 5
6 dB
Select
J3 pin 7
6 dB
Bypass
J3 pin 6
0 High Low High Low High Low
2 High Low Low High High Low
4 Low High Low High High Low
6 High Low High Low Low High
8 High Low Low High Low High
10 High Low High Low High Low

Agilent Technologies E4448A Specifications

General

Brand	Agilent Technologies
Model	E4448A
Category	Measuring Instruments
Language	English