Professor Mason
May 5th Class
Oscilloscope and Cathode Ray Tube
First thing we learned in class was about oscilloscope and Cathode Ray Tube. Our first task was to determine the direction of the electron would go through the wire of a Cathode Ray Tube. The result was that the electron would go to every direction as shown in the picture attached below. When the filament lit up, it would emit electron in every direction. In Cathode Ray Tube, the charge of the electron that go in between all the plates are negative; while the direction of the electrons on plate are attracted to the negative electron, they would go upward or downward. In Cathode Ray Tube, the negative electrons are defined with green light dot going straight line through the plates. In Cathode Ray Tube, there are intensity knob, which control the voltage, knobs that adjust the voltage and time base, knobs that adjust zeroes in vertical and horizontal plate, position knob, which controls the position of the graph to the left or right. Var sweep knob controls how fast the green dot would go depending on the time base.
The graph that goes upward and downward shown in the picture below is a graph of Voltage vs Time. That graph is how the green dot would look like if we take a look closely the dot's movement through the oscilloscope. The period affects how many dots it would produce between a certain period. This graphs is also called a square graph, which makes the beam bounces; when the voltage is on and off, the graph goes up and down.
When we increase the voltage on the deflection plates, the graph on the oscilloscope would shift vertically upward. We found out an equation for F on the electron in a function of q and E, which is [F = Q E]. We also found out an equation of acceleration as a function of q, v, d, and m, which is [a = (q v)/ (d m)], which d is the distance between plates. We also found a new equation of time in this case. A variable t is defined by how much time an electron would pass through the plates, and that is [t = L/V], which L is the length of the plates as shown in the picture on the right. We also figure out the function of Velocity in y component, and that is [Vy = Vx + at], which when simplified, it becomes [Vy = qVL/ mdVx].Experiment with Function Generator
Function generator is a small machine shown in the picture attached above next to oscilloscope. Function generator is a machine that would help the oscilloscope produce a better graph in dots with more precise frequency and voltage based on noise. The first thing we need to experiment with function generator is to attach it with a speaker; then we measure it based on certain frequency. When a function generator is attached to a speaker, the bigger the voltage is, the louder the sound gets. On the other hand, the higher the frequency is, the higher the pitch is. The next thing we needed to do in "Electronics" Lab is to describe the sound we hear when the function generator is set up with a sine wave and 96 Hertz; the result was that it sounded like a continuous soft farting noise. Then, the sound it would produce when we used the triangle and square wave output were that the triangle one sounded like a plane's copter when it's about to start, then the square one is similar to the triangle one, but it has more bass than the triangle one. In conclusion, higher frequency produces higher pitch, and lower frequency produces lower pitch. Changes in amplitude affects the sound in volume; therefore, when the amplitude increases, the volume is also increased.
Experiment with Oscilloscope Controls
Oscilloscope is a big machine shown in picture attached above. In oscilloscope, the intensity knob controls the brightness of the green dot, and the power/illumination knob is used to turn on and off of the oscilloscope. The focus knob controls the thickness of the green dot. The time base knob controls how fast the green dots would move, and the position knob controls the position of the green dot to the left or to the right. The sensitivity knob is used to shift the dot vertically depends on what we use; for example, we used a battery, and we adjust the sensitivity knob to 2 volts, which would shift the green dot vertically upward. In the next experiment, we needed to connect the battery in series with the tap key to the CH 1 input plug. With the CH 1 VOLTS/DIV set to 1 V and the TIME/DIV set to 0.1 s, we tried tapping the key. We tried several different settings of the VOLTS/DIV knob. In conclusion, the relationship between the VOLTS/DIV setting and the vertical deflection of the spot is that the height of the dot jumped when tapped. In the next experiment with oscilloscope and function generator, we needed to set the function generator to 96 Hz, then we needed to use the oscilloscope to determine the period of a sinusoidal wave form. The result was 7 ms or 0.007 s based on the wave reading, while the green dot was in a wave form. Next, we needed to calculate the period calculated on the basis of the frequency reading on the dial, and the result was [T = 1/F], which becomes [T = 1/96 Hz = 0.0104]. Next, we needed to experiment with the DC offset control on the function generator and AC/DC button on the oscilloscope; the last thing we tried playing with it was that the green dot shifted vertically.
We also needed to switch to sinusoidal wave and square wave outputs on the function generator and take a picture of each waveform. This graph on the left picture attached shows how the square wave would look like on the oscilloscope. 
After we were all done with sinusoidal and square wave, the next thing we needed to do was to do and experiment with the frequency dial and multipliers on the function generator and the time base control on the oscilloscope. The changes in these settings affect the wave form as the frequency dial adjusts period of waves; while, multipliers affect its amplitude; time base control [Time/DIV] changes the value of seconds per unit and zooming in to the graph.
AC/DC output and Wallwart
In this experiment, we first needed to connect a small DC wallwart to the oscilloscope, then measure the characteristics of the transformers; we also needed to connect an AC transformer to the input of the oscilloscope and measure the output.
First, we did in in DC source (we found out that the source is DC because we looked at the output, and it says DC). The graph shown in the picture on the left shows a wave of DC source at 0.5 ms time base control. The graph shown on the right shows a wave form of DC source at 0.1 s time base control on oscilloscope going slowly to the right.
After we finished the DC source, we did an experiment with an AC source. The wave shown in the picture attached on the left shows a wave of AC source at 2 ms at time base control. On the other hand, the wave shown in the picture attached on the right shows a wave form of AC source at 0.1 s at time base control on oscilloscope going slowly to the right.
After we finished the AC and DC part, we moved on to the next part, which was Lissajous Figures. First, we needed to connect an AC transformer to CH 1, then CH 2 to function generator. Next, set the frequency of function generator to 30 Hz. Then, we needed to adjust the frequency to make the wave moves as slow as possible. The wave shown in the picture attached on the left is the result of CH1 and CH 2 experiment with the wave going as slow as possible. The picture on the right shows the same wave that is put in XY mode; however, professor Mason played with the graph using two function generator, and it became complicated like that.Mystery Box Experiment
The mystery box is shown in the picture attached on the left. We needed to attach the oscilloscope to these mystery box along with all the possibilities.
The picture on the right is a square wave created from RED and BLACK AC source.
RED and BLUE AC source also create the same wave as Red and Black AC as shown in the left picture.
RED and GREEN AC source also create the same wave as Red and Black AC source as shown on the left picture.
The picture on the right is a square wave created from RED and BLACK DC source; it shifted upward from the AC source.
The picture on the left shows a wave with no signal from BLACK & GREEN and BLACK & BLUE all from DC source; the straight line from the axis shifted upward.
GREEN & BLUE DC source's wave also shifted upward, but only a little bit, unlike this picture.
BLACK & GREEN AC source did not create any wave because it had no signal.
BLACK & BLUE AC source did not create any wave because it had no signal.
GREEN & BLUE AC source also did not create any wave because it had no signal.
RED & BLUE DC source created a square wave similar to red and black AC source, but the difference is this one is shifted downward.
It also applies the same thing for RED & GREEN DC source; it creates the same wave as the picture on the left.
RED & YELLOW AC and DC sources would create a straight line wave with a little spikes around the wave, which means that it created a signal with a little noise. Both AC and DC has the same picture as shown on the left.
RED and BLUE AC source also create the same wave as Red and Black AC as shown in the left picture.
RED and GREEN AC source also create the same wave as Red and Black AC source as shown on the left picture.
GREEN & BLUE DC source's wave also shifted upward, but only a little bit, unlike this picture.
BLACK & BLUE AC source did not create any wave because it had no signal.
GREEN & BLUE AC source also did not create any wave because it had no signal.
It also applies the same thing for RED & GREEN DC source; it creates the same wave as the picture on the left.
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