ECE20L-2 – ELECTRONICS LABORATORY
ACTIVITY 1.2 – FAMILIARIZATION OF COMPONENTS AND EQUIPMENTS
ECE20L-2 / E03
Part 1 – Resistor Color Code
Color Band Nominal Resistance Minimal Value Maximum Value
Value
1. Red, Yellow, Red 2.4 kΩ 1.920 kΩ 2.48 kΩ
2. Blue, Brown, Orange, 61 kΩ 57.95 kΩ 64.05 kΩ
Gold
3. Green, Red, Brown 520 Ω 416 Ω 624 Ω
4. Gray, Green, Black, Silver 85 Ω 76.5 Ω 93.5 Ω
5. Green, Red, Silver 0.52 Ω 0.416 Ω 0.624 Ω
6. Blue, Brown, Red, Silver 6.1 kΩ 5.49 kΩ 6.71 k Ω
7. Red, Blue, Gold 2.6 Ω 2.08 Ω 3.12 Ω
8. Brown, Red, Silver 120 mΩ 96 mΩ 144 mΩ
9. Brown, Brown, Brown 110 Ω 88 Ω 132Ω
10. Green, Violet, Orange 57 kΩ 45.6 kΩ 68.4 kΩ
11. Yellow, Orange, Black 43 Ω 34.4 Ω 51.6 Ω
12. Blue, Grey, Red 6.8 kΩ 5.44 kΩ 8.16 kΩ
13. Yellow, Brown, Red 4.1 kΩ 3.28 kΩ 4.92 kΩ
14. Blue, Red, Silver, Gold 0.62 Ω 0.589Ω 0.651Ω
15. Brown, Black, Black, 10 Ω 9.5 Ω 10.5 Ω
Silver
Part 2 – Multimeter
1. What will this voltmeter register when connected to a battery as shown (assume a battery
voltage of 6 volts)? Explain your answer.
- This will not show any voltage reding because you need to measure voltage between two
points
2. What will this voltmeter register when connected to a battery as shown (assume a battery
voltage of 6 volts)? Explain your answer.
- When you connect it in reverse, it will show a negative value. So, the voltmeter will be
reading -6 volts
3. If we were to connect a voltmeter directly to an ohmmeter, what would you expect to see the
ohmmeter register, for resistance between its test leads?
- If you connect a voltmeter to a ohmmeter directly, the ohmmeter should register a very
high resistance
4. Many electronic circuits use what is called a split or a dual power supply:
Determine what a digital voltmeter would indicate if connected between the following points:
a) Red lead on Ä”, black lead on ground
-It will be 15 volts
b) Red lead on “B”, black lead on ground
-It will be -15 volts
c) Red lead on Ä”, black lead on “B”
-It will be 30 volts
d) Red lead on “B”, black lead on Ä”
-it will be -30 volts
5. Determine what these four voltmeters (A, B, C, D) will register when connected to this circuit in
the following positions (assume a battery voltage of 6 volts):
• Voltmeter A = 6 volts
• Voltmeter B = 0 volts
• Voltmeter C = 6 volts
• Voltmeter D =0 volts
Part 3 – Capacitor
1. Identify 3 types of capacitors, and list at least 2 of their characteristics.
Film Capacitors
- they are the most commonly available of all types of capacitors. Film type capacitors are
available in capacitance ranges from as small as 5pF to as large as 100uF depending upon the
actual type of capacitor and its voltage rating.
Electrolytic Capacitors
- Electrolytic Capacitors are generally used when very large capacitance values are required.
Here instead of using a very thin metallic film layer for one of the electrodes, a semi-liquid
electrolyte solution in the form of a jelly or paste is used which serves as the second electrode.
Ceramic Capacitors
- Ceramic Capacitors or Disc Capacitors as they are generally called, are made by coating two
sides of a small porcelain or ceramic disc with silver and are then stacked together to make a
capacitor. For very low capacitance values a single ceramic disc of about 3-6mm is used.
2. Why should capacitor be discharged before testing with a multimeter?
- This is to avoid damage to your device. You can use a regular screwdriver to discharge the
capacitor
3. How is testing of non-polarized to polarized capacitor differ?
- In a polarized capacitor, connect the red probe with the positive terminal of the capacitor
and the black probe to the negative terminal. In a non - polarized capacitor, connect it either
way as they do not have polarity.
4. A capacitor has a label on it saying, “100 WVDC”. What does this label mean? What is the
consequence of exceeding this rating?
- This means that the capacitor’s working voltage is 100 volts in Direct Current. Failure of the
dielectric material will result from exceeding this voltage rating. In electrolytic capacitors
especially, the failure can be violent.
5. A 10 μF capacitor is charged to a voltage of 20 volts. How many coulombs of electric charge are
stored in this capacitor?
- The charge stored in the capacitor will be 200 μC
PART 4- OSCILLOSCOPE
The figure shows a sample oscilloscope
Describe what does the following controls of the oscilloscope do.
VERTICAL CONTROLS
POSITION – vertical position control allows you to adjust the waveform to move upwards or
downwards.
SCALE (Volts per Division) – The vertical scale knob controls the amount of voltage represented by a
vertical division on the graticule.
BANDWIDTH LIMIT – By limiting the bandwidth, you reduce the noise that sometimes appears on the
displayed waveform, providing you with a more defined signal display.
INPUT COUPLING – The input coupling is the connection from your test circuit to the oscilloscope.
o DC COUPLING – DC coupling shows all the input signal
o AC COUPLING – AC coupling blocks the DC component of a signal so that you see the
waveform centered around zero volts.
o GROUND COUPLING - The ground coupling disconnects the input signal from the vertical
system, which lets you see where zero volts is located on the screen.
HORIZONTAL CONTROLS
POSITION – This allows you to position your waveform from left to right
SCALE (Seconds per Division) – the time axis of the oscilloscope display.
AUTOSET – This automatically identifies the type of waveform and adjust controls to produce a usable
display of the input signal
TRIGGER CONTROLS – trigger control synchronizes the horizontal sweep at the correct point of the
signal. This is essential for clear signal characterization.
SOURCE – determines which signal is compared to the trigger settings
LEVEL – It stabilizes a repeating signal, or to trigger on a single event and provide the basic trigger
point definition and determine how a waveform is displayed.
SLOPE - determines whether the trigger point is on the rising or the falling edge of a signal. A rising
edge is a positive slope and a falling edge is a negative slope.
