Fluke 9640A Series, Инструкция по эксплуатации

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Local Operation
Operating the Instrument
3
3-47
Creating a Frequency-Modulated Output Signal
Use the following procedure to create a frequency-modulated output signal and, if
required, to define the incremental step values by which the frequency, level, modulation
rate and deviation of the output signal can be increased and decreased. Refer to Table
3-17 for a list of the fields available on the
Modulation
screen and the limits associated
with each field.
1.
Press

.
2. Press the
Modulation Select
soft key to expand the selections at the bottom of the
screen.
3. Press the
FM
soft key to activate the
FM Modulation
screen.
4. Select the
Frequency
field, and enter the desired output frequency.
5. If a frequency step is required, press the
Frequency
soft key again until a
Freq Step
field appears at the bottom of the screen.
a.
Select the
Freq Step (Step Size)
field.
b. Enter the desired frequency step in the field.
6. Select the
Level
field and enter the desired output level.
7. If a level step is required, press the
Level
soft key again until a
Level Step
field
appears at the bottom of the screen.
a.
Select the
Level Step (Step Size)
field.
b. Enter the desired level step in the
Level Step
field.
8. Select the
Mod Rate
field and enter the desired output rate.
Notice that the
Mod Rate
field includes a definition of the modulating waveform,
Sine
,
or External
. To select a specific waveform proceed as follows:
a. Press the
Mod Prefs
soft key.
b. Select the
FM Mod Waveform
field.
c. Select the appropriate waveform (
Sine
or
External
).
d. Enable, if required, the Modulation Trigger Output, Rising or Falling Edge.
e. If an External Modulation waveform is in use, select either AC or DC coupling
f. Return to the
FM Modulation
screen by pressing the
Exit
soft key.
9. If a rate step is required, press the
Rate
soft key again until a
Rate Step
field appears
at the bottom of the screen.
a.
Select the
Rate Step (Step Size)
field.
b. Enter the desired rate step in the
Rate Step
field.
10. Select the
Deviation
field and enter the desired deviation frequency. If External
Modulation is in use, the entry is the required deviation sensitivity value in Hz, kHz
or MHz per Volt.
11. If a deviation step is required, press the
Deviation
soft key again until a
Dev Step
field appears at the bottom of the screen.
a.
Select the
Dev Step (Step Size)
field.
b. Enter the desired deviation step in the
Dev Step
field.