Agilent Technologies PSA Series Service Manual page 77

If the DC/AC Coupling modes are not properly functioning, a similar
table can be used.
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
20 dB and a 30 dB section. Verify that the attenuators are receiving the
correct switching sequences by using the following tables.
Table 3-1 A15 Settings
Attenuation 6 dB
(dB) Select
J4 pin 9
0 High
6 Low
10 High
20 High
30 High
40 High
50 High
60 High
70 Low
Chapter 3
Coupling DC Block Select
DC
AC
Figure 3-4, A14 has two 2 dB sections and A15 has a 6 db, a 10 dB, a
6 dB 10 dB
Bypass Select
J4 pin 4 J4 pin 2
Low High
High High
Low Low
Low High
Low High
Low Low
Low High
Low Low
High Low
Troubleshooting the RF Section (E4440A, E4443A, E4445A)
RF Section Description (E4440A, E4443A, E4445A)
J3 pin 9
High
Low
10 dB 20 dB 20 dB
Bypass Select Bypass
J4 pin 1 J4 pin 8 J4 pin 5
Low High
Low High
High High
Low Low
Low High
High High
Low Low
High Low
High Low
DC Block Bypass
J3 pin 4
Low
High
30 dB 30 dB
Select Bypass
J4 pin 7 J4 pin 6
Low High Low
Low High Low
Low High Low
High High Low
Low Low High
Low Low High
High Low High
High Low High
High Low High
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