2. CATHODE RAY OSCILLOSCOPE

3. Functional Units a) Electron GunElectron Gun b) Evacuated TubeEvacuated Tube c) Deflecting SystemDeflecting System d) Time BaseTime Base e) Trigger CircuitTrigger Circuit

4. Electron Gun

5. a) Heating Filament b) Cathode c) Grid d) Electron lens Link to figure Return

6. Evacuated Tube Vacuum space Screen Graphite inner wall Shielded from electric and magnetic fields ReturnLink to figure

7. Deflecting System X-plates Y-plates X and Y Deflection Amplifiers X-shift Control Y-shift Control Sensitivity Control ReturnLink to figure

8. Time Base Sawtooth potential difference Time period control ReturnLink to figure

9. Trigger Circuit Maintain a stable trace Trig level control Trigger time base automatic triggering

10. USES OF CRO a) VoltmeterVoltmeter b) Display of waveformsDisplay of waveforms c) Measurement of short time intervalsMeasurement of short time intervals d) Measurement of frequencyMeasurement of frequency e) Display of phase relationshipDisplay of phase relationship f) Comparison of frequenciesComparison of frequencies

11. Voltmeter Calibration D.C. voltmeter A.C. voltmeter Advantages over moving-coil voltmeters Return

12. Display of Waveforms Return magnify

13. Measurement of Short Time Intervals Calibrate for the time base Measure a very small time interval, e.g. measurement of sound speed in a metal rod Return

14. Measurement of Frequency Signal applied to Y-plates ‘Lock’ the trace Choose a suitable time base Determine the period, T Calculate the frequency Return

15. Display of Phase Relationships Return Computer Simulation

16. Comparison of Frequencies Lissajous’ figures Frequency ratio

17. EXAMPLE