Keysight Technologies Infiniium 90000A Series, Руководство по обслуживанию

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Testing Performance
3
90000 A-Series Service Guide 35
7
Set the generator to apply a 50 MHz sine wave with a peak-to-peak amplitude
of about four divisions.
Use the following table to determine the approximate required signal
amplitude.
The amplitude values in the table is not absolutely required. If your generator is
unable to produce the recommended amplitude, then set the generator to the
highest value that does not produce a vertically clipped signal on the
oscilloscope.
Nominal Generator Amplitude Settings
8
Measure the input power to the oscilloscope channel and convert this
measurement to Volts RMS using the expression:
For example, if the power meter reading is 4.0 μ W, then
Vin = (4.0*10
-6
* 50
Ω
)
1/2
= 14.1 mVrms.
Record the RMS voltage in the Analog Bandwidth—Maximum Frequency Check
section of the Performance Test Record (Vin @ 50 MHz).
9
Press [Clear Display] on the oscilloscope and record the scope V rms reading in
the Analog Bandwidth—Maximum Frequency Check section of the Performance
Test Record (Vout @ 50 MHz).
10
Calculate the reference gain as follows:
Oscilloscope
Vertical Scale
Generator Signal
Amplitude (Vp-p)
Generator Signal
Amplitude (dBm)
5 mV/div 0.02 -30
10 mV/div 0.04 -24
20 mV/div 0.08 -18
50 mV/div 0.20 -10
100 mV/div 0.40 -4
200 mV/div 0.80 +2
500 mV/div 2.0 +10
1 V/div 4.0 +16
V
in
P
meas
50
Ω ×
=
NOTE
For all oscilloscope readings in this procedure, use the mean value in the Results area at the
bottom of the screen.