Sistemas de comunicación no verbales en A-RONNE:

● Resistors: 12O (2), 100 O (2), 2.7 kO (2), 3.9 kO, 8.2 kO, 1.1 MO, 15 kO, 470O, 18 O, 56 kO, 4.7 kO

● Digital multimeter

Background information

● The Universal Solderless Breadboard, or usually known as the bread-board, is one type of circuit board. It offers an easy way to change com-ponents or wire connections on the breadboard without soldering.

● The breadboard is a good training tool and is usually used in the lab to perform experiments on electric or electronic circuits, or for professionals to build temporary electrical or electronic circuits to try out ideas for circuit designs.

● Figure L1.1 is a photograph of a small breadboard, and Figure L1.2 is what the underneath of the breadboard looks like.

● The breadboard contains an array of holes where the leads of components and jumper wires can be inserted. The bottom of the board has many strips of metal, which is laid out as shown in Figure L1.2. These strips connect the holes on top of the board. The top and bottom rows will be used to connect the power supply. Figure L1.3(a) is a simple circuit, and Figure L1.3(b) shows how to build this circuit on the breadboard.

Resistor colour code guide (four band)

● Most resistors are very small and it is hard to print the values on them.

Usually the small resistors have different colour bands on them, and the Figure L1.1 A breadboard

Figure L1.2 The underneath of the breadboard

standard resistor colour code can be used to interpret the values of dif-ferent resistors.

● To determine the value of a resistor from the colour band markings, hold the resistor so that the colour bands are closest to the left end as shown in Figure L1.4.

● The first two colour bands on the left side of the resistor represent two digits (0–9), the third band represents the number of zeros to add to the integers (multiplier), and the fourth band represents the tolerance of the resistance.

● The resistor colour code is shown in Table L1.1, and the tolerance of the resistance is shown in Table L1.2.

Note:Memory aid: Better Be Right Or Your Great Big Venture Goes West Source:

http://www.wikihow.com/Discussion:Remember-Electrical-Resistor-Color-Codes

Table L1.1 Resistor colour code

Colour Digit

Black 0

Brown 1

Red 2

Orange 3

Yellow 4

Green 5

Blue 6

Violet 7

Grey 8

White 9

Figure L1.4 Resistor colour bands

+

-R E

(a) (b)

Figure L1.3 Building a simple circuit on the breadboard

Example: If a resistor has colour bands of brown (1), black (0), red (add two zeros) and silver (tolerance is 10%) from left to right side respectively, it indi-cates that its resistance lies between 900 and 1100O:

R¼ 1 000 O  10% ¼ 1 000  100 ¼ 900 to 1100 O

Example: If one needs to find a resistor with the value of 470 O, its colour bands should be yellow (4), violet (7) and brown (add one zero).

Multimeter guide

● A multimeter or VOM (volt–ohm–millimetre) is an electrical and elec-tronic measuring instrument that combines functions of voltmeter, ammeter, ohmmeter, etc. There are two types of multimeters: digital multimeter (DMM) and analog multimeter. DMM is a very commonly used instrument, since it is easier to use and has a higher level of accuracy.

● Method for measuring resistance with a DMM (ohmmeter function):

● Turn off the power supply if the resistor has been connected in the circuit.

● Insert the multimeter’s leads into the sockets labelled COM and V/O as shown in Figure L1.5, and turn on the multimeter.

● Turn the central selector switch pointing to the ohms range (with O sign), and to where the maximum range of the estimated resistor value is closed.

● Make the measurement by connecting the resistor in parallel with the two leads of the multimeter (connect or touch one lead from the multimeter to one end of the resistor, and connect or touch the other lead of the multimeter to the other end of the resistor).

● If measuring an unknown resistor, adjust the multimeter range from the maximum to the lower range until suitable resistance is read.

● Turn off the multimeter.

Note: To get more accurate measurement result, be sure not to grab the resis-tor’s leads with your hands when you are measuring resistors, since you will add your own resistance (in parallel) to the resistor. Better insert the resistors into the holes of the breadboard to measure them.

Table L1.2 Tolerance of resistance

Colour Tolerance (%)

Gold +5

Silver +10

Procedure

1. Familiarize with the resistor colour code. Use the resistor colour code chart in Table L1.1 to find the six resistors listed in Table L1.3 from the lab. List the colour band identification for these six resistors, and fill in the ‘Colour code’ and the ‘Resistance range’ columns in Table L1.3.

Table L1.3

Resistor Colour code Resistance range Measured value Example: 470O Yellow, violet, brown,

gold

446.5O7493.5 O 470.5O 12O

100O 2.7 kO 3.9 kO 82 kO 1.1 MO

Figure L1.5 Multimeter

2. Get the multimeter to function as an ohmmeter, and measure the six resistors in Table L1.3 with multimeter and fill in the ‘Measured value’

column in Table L1.3.

3. Construct the circuits shown in Figure L1.6 on the breadboard with the right resistors. Show your circuits to the instructor to get check-up and signature.

Conclusion

The conclusion may include the following information:

● lab objectivities accomplished

● results, errors and error analysis

● problems encountered during the experiment and their solutions

● knowledge and skills obtained from the lab

18 Ω 56 kΩ

470 Ω

⫹ ⫹

⫺

⫺

⫹

⫺ 4.7 kΩ

15 kΩ 12 Ω

100 Ω

2.7 kΩ

12 Ω 100 Ω

2.7 kΩ

3.9 kΩ 1.1 MΩ

8.2 kΩ

Figure L1.6 Construct circuits on the breadboard