Agilent Technologies PSA Series Service Manual page 97

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
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 30 dB
(dB) Select J4
pin 9
0 High
10 High
20 High
30 Low
40 Low
50 Low
60 Low
70 Low
Table 4-2 A14 Settings
Attenuation 2 dB - B
(dB) Select
J3 pin 9
0 High
2 High
4 Low
6 High
8 High
10 High
Chapter 4
Figure 4-4, A14 has two 2 dB sections and one 6dB section. A15 has a
30 dB
Bypass J4 Select J4
pin 4
Low
Low
Low
High
High
High
High
High
2 dB - B
Bypass
J3 pin 4
Low
Low
High
Low
Low
Low
Troubleshooting the RF Section (E4446A, E4447A, E4448A)
RF Section Description (E4446A, E4447A, E4448A)
10 dB 10 dB
Bypass J4
pin 2 pin 1
High Low
Low High
High Low
High Low
Low High
High Low
Low High
Low High
2 dB - A 2 dB - A
Select Bypass
J3 pin 8 J3 pin 5
High Low
Low High
Low High
High Low
Low High
High Low
20 dB 20 dB
Select J4 Bypass J4
pin 8 pin 5
High Low
High Low
Low High
High Low
High Low
Low High
Low High
Low High
6 dB 6 dB
Select Bypass
J3 pin 7 J3 pin 6
High Low
High Low
High Low
Low High
Low High
High Low
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