Tektronix TDS 820, Manual

Page: 38 / 94

Performance Tests
Performance Verification
1Ć24
Table 1-5: Voltage Measurement at 20
_
C to 30
_
C
b
— Without Delay Line
Vertical
Scale
Setting Generator
Voltage
Setting
a
Vertical
Position
Setting
a
Off-
set Set-
ting
a
Measurement Offset Accuracy Limits
100 mV 0.4 V 0 0 V V
1
Record measurement as V
1
–0.4 V 0 0 V V
2
Record measurement as V
2
V
1
– V
2
= 0.7902 V to 0.8098 V
a
Vertical position is set to 0 divisions and vertical offset to 0 V when the oscilloscope is initialized in step 1.
b
Outside the 20
_
C to 30
_
C range, calculate the accuracy limits using the specification.
H
Press MEASURE.
H
Press the main-menu button Select Measurement
H
Press the side-menu button more until the menu label Mean
appears in the side menu (its icon is shown at the left). Press the
side-menu button Mean.
b. Set the vertical scale, generator voltage, position, and offset: Change
the setup to one of the settings listed in Table 1-4 or Table 1-5 that is
not yet checked. (Start with the first setting listed.) Table 1-4 is for
instruments with a delay line (standard instrument). Table 1-5 is for
instruments without delay lines (Option 1D).
H
Set the vertical SCALE to the setting in the table.
H
Set the generator voltage to the setting in the table.
H
Press VERTICAL MENU.
H
Press the main-menu button Position; and then set the vertical
position to the setting in the table.
H
Press the main-menu button Offset; and then set the offset to the
setting in the table.
H
Press CLEAR MENU.
c. Display the test signal: The baseline DC test level was initialized for
all channels in step 1. Be sure
not to use the vertical POSITION knob
while checking any channel for accuracy of voltage measurement,
since varying the position invalidates the check.
d. Read the measurement results at the mean readout on screen.
Record the results for later use. See Figure 1-7.
e.
Check against limits: Do the following subparts in the order listed.
H
Repeat substeps b through e until all settings listed in Table 1-4
or Table 1-5 are checked for the channel under test.
H
CHECK that the calculated voltages are within the limits listed for
the vertical scale and generator voltage settings.