A9 Input Attenuator - Agilent Technologies 8564EC Service Manual

A9 Input Attenuator

1. Perform the "Input Attenuator Accuracy" performance test in the
2. If there is a step-to-step error of approximately 10 dB or more,
3. On the spectrum analyzer, press
4. Step the input attenuator from 0 dB to 60 dB. A "click" should be
5. Monitor the pins of A14U421 with a DVM while setting the input
6. If one or more logic levels listed in
When W11 is disconnected, the +28 V levels listed in
NOTE
page 606
Table 12-4 on page
7. If one or more logic levels listed in
8. If all logic levels are correct, the A9 input attenuator is probably
Chapter 12
8560 E-Series Spectrum Analyzer Calibration Guide.
continue with step 3.
until MAN is highlighted.
heard at each step. The absence of a click indicates faulty attenuator
drive circuitry. It will be necessary to use the DATA keys to enter an
input attenuator setting of 0 dB (the step key will not allow selecting
0 dB input attenuation).
attenuator to the values listed in
incorrect, disconnect W11 from A14J6 and repeat step 5 using
Table 12-4 on page 607.
are floating and will read approximately 0.2 V. Refer to
607.
incorrect with W11 disconnected, troubleshoot the A14 frequency
control assembly.
defective.
, and
AMPLITUDE ATTEN AUTO MAN
Table 12-2 on page 606.
Table 12-2 on page 606
Table 12-2 on
Table 12-4 on page 607
RF Section

A9 Input Attenuator

is
is
605