Agilent Technologies 1141A, Руководство пользователя и сервисное руководство

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Adjusting the Probe 3
Probe Adjustment
1141A and 1142A User’s Guide 51
28 Change the function generator settings to a 4 kHz sine wave with a
1.0V
p- p
amplitude.
29 Change the oscilloscope settings to:
30 Adjust C6 ( –LF BANDWIDTH ) for minimum signal amplitude on the
oscilloscope. Again, adjust C6 slowly and press CLEAR DISPLAY
frequently to restart averaging.
Step 4. Adjust the High
Frequency Compensation
This adjustment sequence continues from the Low Frequency
Response and CMRR adjustment. However, it can be done
separately if the probe meets all specifications except bandwidth.
Adjust R13 for unity gain at 200 MHz.
31 Connect the signal generator to the test board and set it for 200
MHz and 300mV
p- p
(107 mV
rms
).
32 Carefully connect the input of the probe to the test board in the
position shown in
Figure 29 .
Figure 29 Signal to +Input
33 Press AUTOSCALE , then measure the peak- to- peak voltage on
channel 1 (Press SHIFT (blue), press
V P-P
, then press
1
).
34
Adjust R13 (
HF COMP
) to make the signal amplitude measurement
on the oscilloscope 300 mV
p- p
, or as close to that as possible.
Adjust slowly and press
CLEAR DISPLAY
frequently to restart
averaging.
Table 14 Oscilloscope Settings
Menu Selection Setting
TIMEBASE (time/div) 50 µs/div
CHAN 1 (sensitivity) 2 mV/div