Keysight InfiniiVision 2000 X Series, Руководство по обслуживанию

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42 2000/3000 X-Series Oscilloscopes Service Guide
2
Testing Performance
2 Set up the power meter.
Set the power meter to display measurements in units of watts.
3 Set up the oscilloscope.
a Press the [Default Setup] key.
b Set channel 1 Coupling to DC .
c With 2000 X-Series oscilloscopes, connect a 50 ohm feedthrough
termination.
With 3000 X-Series oscilloscopes, set channel 1 Imped to 50 Ohm .
d Set the time base to 500 ns/div.
e Set the Volts/Div for channel 1 to 200 mV/div.
f Press the [Acquire] key, then press the Averaging softkey.
g Turn the Entry knob to set # Avgs to 8 averages.
4 Set the signal generator for 1 MHz and six divisions of amplitude.
The signal on the oscilloscope screen should be about five cycles at six
divisions amplitude.
5 Set up the Amplitude measurement
a Press the [Meas] key.
b Press the Clear Meas softkey and then the Clear All softkey.
c Press the Type: softkey and use the Entry knob to select AC RMS - Full Screen
(Std Deviation) within the select menu.
d Press the Add Measurement softkey.
6 Note the oscilloscope AC RMS - FS(1) reading at the bottom of the screen.
(This is the RMS value with any dc offset removed.)
7 Set the power meter Cal Factor % to the 1 MHz value on the calibration chart
on the power sensor.
8 Note the reading on the power meter and covert to Vrms using the expression:
For example, if the power meter reading is 892 uW, then Vin
1MHz
= (892*10
-6
*
50
Ω
)
1/2
= 211.2 mV
rms
.
Vin
1 MHz
Pmeas
1 MHz
50
Ω ×
=