Chapter 3: Testing Performance
To test offset accuracy
3–11
To test offset accuracy
This test checks the vertical offset accuracy.
Specification: ±(1.25% of channel offset + 2% of full scale) at full-resolution channel scale
Equipment Required
Procedure
1
Connect the equipment.
The cabling is the same as that used for the voltage measurement accuracy test. See figure 3-3.
a Use a BNC-to-banana adapter to connect a BNC cable to the power supply.
b Connect a BNC tee to the other end of the cable and connect the tee to channel 1 of the
oscilloscope.
c Connect another BNC cable to the tee at the oscilloscope and connect a BNC tee to the
other end of the cable.
d Connect the blocking capacitor to the BNC tee and connect the BNC short to the blocking
capacitor.
e Connect a BNC-to-banana adapter to the same BNC tee and connect the adapter to the
DVM input.
2 Press Default Setup to set the oscilloscope to default conditions.
3 Select Acquisition from the Setup menu.
4 Select Equivalent Time under Sampling Mode. Enable Averaging, and set the # of
Averages to 32. Click Close.
Setup is the same as that for the voltage measurement accuracy test. See figure 3-4.
5 Use the following table for steps 6 through 12.
6 Select Channel 1 from the Setup menu.
7 Set the vertical Scale to the Volts/div value from the first row of the table. Set the Offset
to the Position value from the first row of the table. Click Close.
Equipment Critical Specifications Recommended Model/Part
Power Supply 0.5 V to 2 Vdc, ±1 mV accuracy Agilent 6114A
Digital Multimeter
(DVM)
Better than 0.1% accuracy Agilent 34401A
Cables (2) BNC Agilent 10503A
Adapters (2) BNC (f) to banana (m) Agilent 1251-2277
Adapters (2) BNC tee (m)(f)(f) Agilent 1250-0781
Blocking capacitor 0.18
µF Agilent 10240B
Shorting cap BNC Agilent 1250-0774
Volts/div Position Supply Tolerance Limits
minimum maximum
200 mV 2.00000 V 2.00 V ±57 mV 1.943 2.057 V
100 mV 1.00000 V 1.00 V ±28.5 mV 0.9715 1.0285 V
50 mV 500.000 mV 500 mV ±14.25 mV 485.75 514.25 mV