Agilent Technologies n5181a, Service Manual, Page: 55 / 202

Agilent N5161A/62A/81A/82A/83A MXG Signal Generators Service Guide
Troubleshooting
No Output Power or Output Power is Unleveled (N5183A)
1-47
6. Let the signal generator sweep until the spectrum analyzer displays a sufficient number of points to provide a good representation of the
power performance across the range of frequencies in the sweep.
7. Using the marker feature on the spectrum analyzer, measure the lowest power level displayed for sweep points between 2.5 GHz and 5
GHz.
• If the measured power is < –5 dBm (for example, –6 dBm):
a. Replace the A3 RF assembly.
b. Go to Chapter 4, "Post-Repair Procedures and Performance Verification" .
• If the measured power is
≥
–5 dBm (for example, –4 dBm), and the signal generator has Option 1EM (RF output on rear panel):
a. Replace the A7 Micro Deck.
b. Go to Chapter 4, "Post-Repair Procedures and Performance Verification" .
• If the measured power is
≥
–5 dBm (for example, –4 dBm), and the signal generator has standard RF output (front output):
a. Turn off the signal generator and reinstall the W13 cable between the A3 RF assembly output and the 20 GHz doubler input.
b. Continue to Checking Attenuator Output Signals >= 3.2 GHz (N5183A) .
Checking Attenuator Output Signals >= 3.2 GHz (N5183A)
1. Remove the external cover and the top inside cover. Refer to Chapter 3, "Assembly Replacement" for instructions on removing the
instrument covers.
2. Using Figure 1-17 on page 44 , remove the attenuator output cable and connect the attenuator output to the spectrum analyzer. (The
attenuator output connector is a 2.4 mm female connector and requires a cable with a 2.4 mm male connector.)
3. Set up the spectrum analyzer:
a. Press
Preset
.
b. Set the reference level to +10 dBm.
c. Set the start frequency to 3.1GHz.
d. Set the stop frequency to the maximum source frequency.
e. Set Trace to Max Hold.
4. Set up the signal generator:
a. Press
Preset
.
b. Press
SWEEP
>
Sweep Type List Step
to Step.
c. Press
Configure Step Sweep
.
• Press
Freq Start
>
3.1
>
GHz
.
• Press
Freq Stop
> <maximum source frequency> >
GHz
.
• Press
# Points
>
501
>
Enter.
• Press
More
>
Step Dwell
>
2
>
msec
.
• Press
Return
>
Return
>
Sweep
>
Freq Off On
to On.
d. Press
RF On/Off
to On.
5. Turn on the signal generator and set it as follows:
a. Press
AMPTD
> <maximum settable power> >
dBm
.
b. Press
AMPTD > ALC Off On
to Off.
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