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i. As a voltmeter.
The time base is switched off while the voltage to be measured is fed through the Y-gain of the CRO. The applied voltage displaces the spot vertically on the screen. The Y-gain control knob can be used to amplify the display on the screen by setting it to a certain value. This is referred to as the sensitivity of the CRO.
Hence the corresponding voltage to the signal on the screen is expressed as;
Voltage (V)= vertical deflection (cm)
x Y-gain setting or sensitivity (volts/cm)
ii. Used to measure frequency
The signal whose frequency is to be measured is fed into the Y-gain and the time base is switched on and
adjusted so that the waveform appears stationary on the screen. Suppose the time base setting is 10ms/cm, it implies that the wave takes 10ms to cover 1cm horizontally. This can be used to determine the time of one
wave i.e period T.
Recall: frequency=1/ period T.
In the example above, suppose the time base is set at 40ms/cm;
Then, period T= number of divisions fitting one wave x time base setting
=4cm x (40/1000) s/cm
=0.16s
Hence frequency of the signal= 1/0.16 =6.25Hz
Other uses of the CRO include:
iii. Measurement of small time intervals.
iv. Measurement of amplitudes of direct and alternating voltages.
v. Display of electrical signals whose variations can be put in the form of voltage.
Moraa orina answered the question on April 12, 2018 at 06:30
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