Use this as a coversheet for your lab writeup. Answer the questions on a separate sheet of paper.

1. Signatures:

   Part 1A: Circuit Board Pattern Checked: _____________________

   Part 1B: Circuit Board Etched Satisfactorily: _______________________

   Part 1C: Basic Circuit Works Properly: _______________________

   Part IV: Tuning verified: _______________________

   Part V: Idea for switch installation approved: _______________________

   Part VI: Final Operation and Questions: (INSTRUCTOR ONLY): _______________

2. In electronics a "schematic diagram" is often used to provide a picture of a given circuit. The schematic diagram Figure 6 uses a symbol to represent each type of component. Resistors are zig-zag lines, capacitors are short parallel lines, and triangles represent amplifiers. Lines generally represent connections between components. On the back of this page (or on the next page) is a schematic of our keyboard circuit. Note that the two amplifiers are located inside the LM324 integrated circuit. The numbers on the lines coming from the amplifier symbols correspond to a particular pin on the integrated circuit. Circle the following items and label: speaker, 100 K resistors, capacitor, brass keys, photoresistor.

3. Describe why pressing a key creates a sound coming from the speaker. In other words, explain how the keyboard works.

4. Explain how the resistance connected to a key affects the pitch of the sound produced?

5. What is the function of electrical resistors? The resistors used in this project are carbon composition resistors. From what materials are these resistors constructed? How is the electrical resistance varied?

6. Describe function of electrical capacitors. What is the basic composition of a capacitor?

7. Why does moving your hand over the photocell result in a variation in the output tone of the keyboard?