Question

Explain how A.C voltage and its frequency is measured using CRO.

Answer 1

Method to Measure Voltage :

1.The simplest way to measure signal is to set the trigger button to auto that means oscilloscope start to measure the voltage signal by identifying the zero voltage point or peak voltage by itself. As any of these two points identified the oscilloscope triggers and measure the range of the voltage signal.

2.Vertical and horizontal controls are adjusted so that the displayed image of the sine wave is clear and stable. Now take measurements along the center vertical line which has the smallest divisions. Reading of the voltage signal will be given by vertical control.
Method to Measure Frequency :
1.Increase the vertical sensitivity to get the clear picture of the wave on the screen without chopping any of its amplitude off. 

2.Now adjust the sweep rate in such a way that screen displays a more than one but less than two complete cycles of the wave.
3.Now count the number of divisions of one complete cycle on the graticule from start to end.
4.Now take horizontal sweep rate and multiply it with the number of units that you counted for a cycle. It will give the period of the wave. The period is the number of seconds each repeating waveform takes. With the help of period, you can simply calculate the frequency in cycles per second (Hertz).