Week 5, 02/08/2016 - 02/12/2016:

1.  Functional check: Oscilloscope manual page 5. Perform the functional check (photo).

For question 1 we performed the functional check, a picture of our results is below!

This picture shows the results of the functional check.

2. Perform manual probe compensation (Oscilloscope manual page 8) (Photo of overcompensation and proper compensation).

For question 2 we manually compensated for our probe. Depending on if you are over or under compensated you can see different results. Turn the screw on the probe to show the proper signals. Two pictures of the compensations are below!

This is the graph of an overcompensated probe.

This is the same picture as above, a properly compensated probe.

3. What does probe attenuation (1x vs 10x) do (Oscilloscope manual page 9)?

When the probe is on 1x, the bandwidth of the Oscilloscope is only 7Mhz. When on 10x you can use the full bandwidth of the Oscilloscope.

4. How do vertical and horizontal controls work? Why would you need it (Oscilloscope manual pages 34-35)?

Horizontal and vertical controls can be adjusted by the knobs on the Oscilloscope. Vertical control allows to shift the wave up or down. Horizontal control allows to shift the wave left  or right. Using them you can adjust the position of all channel and math wave forms. You need it to help compare waves.

5. Generate a 1 kHz, 1 Vpp around a DC 2 V from the function generator (use the output connector). DO NOT USE oscilloscope probes for the function generator. There is a separate BNC cable for the function generator.

a. Connect this to the oscilloscope and verify the input signal using the horizontal and vertical readings (photo). 

After connecting the function generator to the oscilloscope we got a graph. Two pictures of the graph are below. Peak to peak value is 1V.

This is the function we generated. 

This is the same function as above, shifted upward and right.

b. Figure out how to measure the signal properties using menu buttons on the scope.

By pressing the measure button you can see the signal properties of the scope. Do not forget to choose proper channel first. There is a yellow button and a blue button and a both button can help us show wave separate or together. 

6. Connect function generator and oscilloscope probes switched (red to black, black to red). What happens? Why?

The oscilloscope does not read anything when the cables are switched. This is because the probe is the input and that the other grounded. The function generators black cable is also ground, so when you switch the cables it grounds everything.

7. After calibrating the second probe, implement the voltage divider circuit below. Measure the following voltages using the Oscilloscope and comment on your results:

a.  Va and Vb at the same time (Photo)

The two pictures below are our readings of Va and Vb at the same time. Va = 216mV and Vb = 331mV.

This shows Va and Vb spread apart.

This show Va and Vb stacked upon each other.

b. Voltage across R4.

We using the value of Va and Vb to calculate the voltage across R4 to be 115mV.

8. For the same circuit above, measure Va and Vb using the handheld DMM both in AC and DC mode. What are your findings? Explain.

A table of our readings are below. After looking that the measurements we found that Vb = 2Va. All the resistors have the same value and the bottom part connect ground ,which means the Va is the voltage across R5 and Vb is the voltage across R5 and R4. So Vb = 2 Va is proved.

	AC (V)	DC (mV)
Va	.058	26.4
Vb	.1118	52.9

 This is a table of our measurements.

9.For the circuit below

a. Calculate R so given voltage values are satisfied. Explain your work (video)

The video below explains the work that we did to find our value for R7. We calculated that R7 is roughly equal to 6k ohms.

This video explains our work for 9 A.

b.  Construct the circuit and measure the values with the DMM and oscilloscope (video). Hint: 1kΩ cannot be probed directly by the scope. But R6 and R7 are in series and it does not matter which one is connected to the function generator. 

The video below shows our work for 9 B.

This video discusses question 9 B.

10. Operational amplifier basics: Construct the following circuits using the pin diagram of the opamp. The half circle on top of the pin diagram corresponds to the notch on the integrated circuit (IC). Explanations of the pin numbers are below:

a.  Inverting amplifier: Rin= 1kΩ, Rf = 5kΩ (do not forget -10 V and +10 V). Apply 1 Vpp @ 1kHz. Observe input and output at the same time. What happens if you slowly increase the input voltage up to 5 V? Explain your findings. (Video)

We found that for a gain of negative 5 that the output would be multiplied by that. But as you get closer to a certain value the output stops changing. A video below discusses it.

This video discusses 10 A.

b.Non-inverting amplifier: R1= 1kΩ, R2= 5kΩ(do not forget -10 V and +10 V). Apply 1 Vpp@ 1kHz.Observe input and output at the same time. What happens if you slowly increase the input voltage up to 5 V? Explain your findings. (Video)

  
The video below discusses our findings for question 10 B. We found that the gain was roughly 6, but after a certain point the output stopped changing values.

This video discuses 10 B. It was wrongly labeled 9 B.