4.2Using the Oscilloscope to Measure Waveforms

ECE 100IL-2

Session: (Tuesday or Thursday?)
(Student A) Name: / ID#: / E-mail:
(Student B) Name: / ID#: / E-mail:
Date: / Bench #

IL-2 Laboratory Data

Each student is to submit this file of observed data to their individual Course Book account at the end of this session. Use the supplied filename of il2data.doc.

4.2Using the Oscilloscope to Measure Waveforms

Set up the oscilloscope as per section 4.1.

Table 1.

Oscilloscope Controls:
Ch-1 input switch to "GND"
VOLTS/DIV switch is rotated
(outer dial)
VOLTS/DIV vernier is rotated
(inner dial)
TIME/DIV control is rotated
(outer dial)
TIME/DIV vernier is rotated
(inner dial)
Function Generator OUTPUT for frequency dial (vernier) is rotated.
Function Generator OUTPUT for RANGE selector pushed.
Function Generator OUTPUT for AMPLITUDE control rotation.

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ECE 100IL-2

2Measure Rout of the function generator=s output terminals

Table 2. Output resistance of the Function Generator

B&K
Function
Generator
Terminals / Vopen circuit / Vopen circuit /2 / Rdecade
measured(DMM) / R
shown on
the front
panel
Scope
Volts/
div / #divs / Volts
VP-P / Scope
Volts/
div / #divs / Volts
VP-P / ohms / DMM
range
8,9 / 600 ohms

3.Using the oscilloscope to measure the function generator frequency.

Table 3.

Time for one cycle of the waveform
(ie: One cycle is one period) / Frequency / Function
Gen. Freq.
Range
__s/div / # of divisions / Total Time
___seconds / Hz / Setting
10

4.Peak to peak voltage value versus R.M.S. voltage value.

Table 4.

Oscilloscope display / DMM voltmeter indication
Set
4.0 volts peak-peak
+/-5% / Range:______/ VRMS

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ECE 100IL-2

4.3Triggering the Oscilloscope

1.Investigating the trigger controls.

Table 5.

Observation
Set to AUTO sweep mode / Adjust TRIGGER LEVEL control
Pick a reference point on the waveform / Adjust TRIGGER LEVEL to determine how many degrees the trigger point can be moved on the waveform. / degrees = ______
Pull out TRIGGER level control to change to -slope / Adjust TRIGGER LEVEL as above. / degrees = ______
Pull out SWEEP LENGTH control
for x5 (or x10)

2.Investigating channel input and trigger source.

Table 6.

INPUT CHANNEL / TRIGGER SOURCE / 1000 Hz waveform
CH-1 (Stable?) / 600 Hz waveform
CH-2 (Stable?)
1 / 1 / ----
2 / 1 / ----
1 / 2 / ----
2 / 2 / ----

4.4Oscilloscope Input AC and DC Coupling

1.The Half-Power frequency for the AC coupling capacitor.

Table 7.

Coupling / Voltage / FREQUENCY MEASURED
AC / 0.707 x 8 volts peak-peak
= 5.6 VP-P
Adjust the frequency until this voltage is reached. / Sec/div: ______
#divs: ______
______Hz
DC / V/div: ______
#divs: ______
______VP-P / Same as above

2.Displaying a DC voltage.

3.Displaying a Squarewave with DC coupling.

4.Displaying a Squarewave with AC coupling.

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ECE 100IL-2

4.5The Oscilloscope X-Y Mode

Which channel input signal causes the Y deflection (vertical)?
Which channel input signal causes the X deflection (horizontal)?

What angle is the display deflection with respect to the horizontal axis?

4.6The Oscilloscope Differential Mode

What is the peak to peak value of the displayed waveform?
V/div: ______
#divs: ______VP-P

4.7Measuring OFF-GROUND Voltages

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ECE 100IL-2

2. & 3.

Table 8.

Measure
Oscilloscope / Measure
DMM
Vs / V/div: ______
#divs: ______/ ______VPK / Range:_____ / ______VRMS
V1 / V/div: ______
#divs: ______/ ______VPK / Range:_____ / ______VRMS
V2 / V/div: ______
#divs: ______/ ______VPK / Range:_____ / ______VRMS
Angle
Theta between Vs and V2 / Sec/div: _____
#divs: _____ / ______degrees(Do not invert ch.2 for this measurement)

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