Fluke 9640A Series, Инструкция по эксплуатации

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9640A
Instruction Manual
3-44
Defining an Amplitude-Modulated Output Signal
Use the following procedure to create an amplitude-modulated output signal and, if
required, to define the incremental step values by which the frequency, level, modulation
rate and depth of the output signal can be increased and decreased. Refer to Table 3-16
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
display.
3. Press the
AM
soft key to select amplitude modulation and return to the main 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. 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. 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 level.
Notice that the
Mod Rate
field includes a definition of the modulating waveform,
Sine
,
Tri
(triangle), or
External
. To select a specific waveform proceed as follows:
a. Press the
Mod Prefs
soft key.
b. Select the
AM Mod Waveform
field.
c. Select the appropriate waveform (
Sine
,
Triangle
, 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
AM Modulation
screen by pressing the
Exit
soft key.
9. If a rate step is required, press the
Rate
soft key again. 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
Depth
field and enter the desired output level (percent only). If External
Modulation is in use, the entry is the required depth sensitivity value in percent per
Volt.
11. If a depth step is required, press the
Depth
soft key again. A
Depth Step
field
appears at the bottom of the screen.
a.
Select the
Depth Step (Step Size)
field.
b. Enter the desired depth step in the
Depth Step
field.
12. To make the amplitude-modulated signal available as an RF Output signal,
press

.
13. To step carrier frequency, carrier level, modulation rate, or modulation depth, select
the appropriate field and use the cursor keys to increase or decrease the output level
by the amount previously entered in the step field
(Step Size)
.