cathode ray oscilloscope and related experiments

Download Cathode ray oscilloscope and related experiments

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  • 1. Fourier analysis
    Resonating LCR circuit with damping effect
    Cathode ray oscilloscope and related experiments.
    Trisha Banerjee @ 2010

2. Inside construction
Numbers in the picture indicate: 1. Deflection voltage electrode; 2. Electron gun; 3. Electron beam; 4. Focusing coil; 5. Phosphor-coated inner side of the screen
Trisha Banerjee @ 2010
3. Trisha Banerjee @ 2010
4. Time base control
Intensity control
Focus control
Trisha Banerjee @ 2010
5. Examples of use
Trisha Banerjee @ 2010
6. Movingthe initial line up and down
Trisha Banerjee @ 2010
7. Pictures of use
AC hum on sound
Sum of a low-frequency and a high-frequency signal.
Dual trace, showing different time bases on each trace
Bad filter on sine.
Trisha Banerjee @ 2010
8. Oscilloscopes are commonly used when it is desired to observe the exact wave shape of an electrical signal. In addition to the amplitude of the signal, an oscilloscope can show distortion and measure frequency, time between two events (such as pulse width or pulse rise time), and relative timing of two related signals. Some modern digital oscilloscopes can analyze and display the spectrum of a repetitive event. Special-purpose oscilloscopes, called spectrum analyzers, have sensitive inputs and can display spectra well into the GHz range. A few oscilloscopes that accept plug-ins can display spectra in the audio range.
Focus control
This control adjusts CRT focus to obtain the sharpest, most-detailed trace. In practice, focus needs to be adjusted slightly when observing quite-different signals, which means that it needs to be an external control. Flat-panel displays do not need a focus control; their sharpness is always optimum
Intensity control
This adjusts trace brightness. Slow traces on CRT 'scopes need less, and fast ones, especially if they don't repeat very often, require more. On flat panels, however, trace brightness is essentially independent of sweep speed, because the internal signal processing effectively synthesizes the display from the digitized data.
Trisha Banerjee @ 2010
9. Timebase Controls
These select the horizontal speed of the CRT's spot as it creates the trace; this process is commonly referred to as the sweep. In all but the least-costly modern 'scopes, the sweep speed is selectable and calibrated in units of time per major graticule division. Quite a wide range of sweep speeds is generally provided, from seconds to as fast as picoseconds (in the fastest 'scopes) per division. Usually, a continuously-variable control (often a knob in front of the calibrated selector knob) offers uncalibrated speeds, typically slower than calibrated. This control provides a range somewhat greater than that of consecutive calibrated steps, making any speed available between the extremes.
Horizontal position control
The horizontal position control moves the display sidewise. It usually sets the left end of the trace at the left edge of the graticule, but it can displace the whole trace when desired. This control also moves the X-Y mode traces sidewise in some 'scopes, and can compensate for a limited DC component as for vertical position.
Trisha Banerjee @ 2010
10. Object :-
a) Finding the Fourier harmonics by using the Fourieranalysis.
Apparatus:-ac generator ,CRO, Fourier kit.
b)To study the series and parallel LCR circuit and plot the resonance curve
at constant frequency and capacity.
Apparatus:LCR kit , inductance coil.
Trisha Banerjee @ 2010
11. a)
Ac frequency generator
Fourier wave form type kit
Fourier analysis experimentwhole setup
Trisha Banerjee @ 2010
12. b)
Resonating circuit kit
Air core inductance (for studyingthe resonating in LCR and its damping effect)
Trisha Banerjee @ 2010
13. Some of the brief features and experiment data of LCR resonant circuit
1) Circuit diagram for series LCR :-
Trisha Banerjee @ 2010
14. Graph representation
Series LCR having max current at cont capacity 700pF
Series LCR having max current at cont frequency at 50 Hz
Trisha Banerjee @ 2010
15. 2) Circuit diagram for parallel LCR:-
Trisha Banerjee @ 2010
16. Graph representation
Parallel LCR having max current at cont capacity 700pF
Parallel LCR having max current at cont frequency at 50 Hz
Trisha Banerjee @ 2010


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