Scribd
Upload
301 views5 pages

Expt No 1

The document describes an experiment to measure the frequency, time period, AC and DC voltages of sine and square waves using an oscilloscope (CRO). It also aims to test components like diodes and transistors. The procedure involves connecting a signal generator and transformer to the CRO and measuring the waveforms. The peak, peak-to-peak values and frequency are calculated by adjusting the timebase and voltage settings. Diodes and transistors are also tested in different biasing configurations and their patterns are observed on the CRO display.

Uploaded by

sanju
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as DOCX, PDF, TXT or read online on Scribd
301 views5 pages

Expt No 1

The document describes an experiment to measure the frequency, time period, AC and DC voltages of sine and square waves using an oscilloscope (CRO). It also aims to test components like diodes and transistors. The procedure involves connecting a signal generator and transformer to the CRO and measuring the waveforms. The peak, peak-to-peak values and frequency are calculated by adjusting the timebase and voltage settings. Diodes and transistors are also tested in different biasing configurations and their patterns are observed on the CRO display.

Uploaded by

sanju
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as DOCX, PDF, TXT or read online on Scribd
You are on page 1/ 5

EXPERIMENT NO: 1

AIM: MEASUREMENT OF FOLLOWING USING CRO

a) Frequency /time measurement of sine and square wave


b) AC and DC voltages
c) Component testing (diode & transistor)

APPARATUS REQUIRED: CRO, Signal generator, transformer, diode


&transistor.

THEORY

AC FUNDAMENTALS

Alternating quantity: A quantity in which the magnitude and direction change


with respect to time is called an alternating quantity.

Example: sinusoidal quantity

Cycle :One complete set of changes in magnitude and direction of any


alternating quantity is called a cycle

Period:Time taken by an alternating quantity to complete one cycle is called


period. Its unit is seconds.

AC WAVEFORM:

Fig.1.Wave form with amplitude and peak-peak voltage & time period.
Fig.2.Wave form with peak voltage & RMS voltage.

FREQUENCY: The number of cycles completed by an alternating quantity per


second is called frequency. Its unit is Hertz.

PEAK VALUE OR AMPLITUDE: The maximum value that an alternating


quantity attains during a cycle is called peak value or Amplitude. There are
positive and negative peak values. The magnitude between these two peaks is
called peak-peak value.

PROCEDURE:

1. Output of the function generator is connected to one of the channels of CRO


through a probe.
2. Focus and intensity knobs in CRO are suitably adjusted to observe both the
signal. If there is any problem in tracing the signal position X and Y position
knobs are suitably adjusted.
3. Function generator is switched on. Sinusoidal quantity is chosen as the output
signal. Amplitude of the sinusoidal quantity is varied and maintained at a
particular value

4.Frequency of the sinusoidal quantity is varied and maintained at a particular


value.
5.The sinusoidal output of function generator is observed using CRO by
enabling AC knob

6.peak value ,peak-peak value of the sinusoidal waveform are observed by


noting the number of divisions in Y axis CRO monitor and the value of the
voltage in the voltage base knob.

7. Number of divisions in X axis of CRO monitor and value of the time in the
time base knob are noted. Time period of the sinusoidal wave is obtained by
multiplying the number of divisions in X axis of CRO monitor and value of the
time in the time base knob.

8.Reciprocal of the time period is the frequency of the sinusoidal waveform.


9.Frequency can also be checked by noting the digital value in the function
generator.

10.Switch on ac input of step down transformer. Keeping CRO channel in AC


mode connect two ends of transformer to probe. Calculate Vm from CRO.

11.Adjust Channel of CRO to reference. Switch on DC power supply and


connect to CRO. Increase DC supply in steps and calculate the vertical shift of
reference line .

12.Select component testing mode of CRO and Select X-Y mode .Connect
Diode and Transistor to test in port .

14.Observe the patterns of forward bias and reverse bias of Diode.

15. Observe the patterns of EB junction and CB junction of Transistor.


CRO DISPLAY

TABULATION:

No. of No. of Voltage Time Peak Time Frequency


S.No. divisions in divisions base Base to Period (Hertz)
X-axis of in Y-axis reading reading Peak ( m Sec)
CRO of CRO (Volt) ( m Sec) Value
monitor monitor (Volt)

CALCULATION:
Frequency =1/ time period

Vm=√ 2.Vrms

RESULT: Measured Time period, Frequency, Amplitude, AC voltage, DC


voltage and component tested (Diode &Transistor).

You might also like