Conrad 10062 User manual

Imprint
© 2011 Franzis Verlag GmbH, 85586 Poing
www.elo-web.de
Author: Thomas Riegler and Burkhard Kainka
ISBN 978-3-645-10062-5
Produced on the order of Conrad Electronic SE, Klaus-Conrad-Straße 1, D92240 Hirschau/Germany.
All rights reserved, including the rights of photo-mechanical reproduction and storage in electronic media.
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should be observed as such. The publisher essentially uses the manufacturer’s spellings for the product desig-
nations. All circuits and programmes introduced in this book were developed, tried and tested with the great-
est possible care. Nevertheless, mistakes in the book and software cannot be fully excluded. The publisher and
author do not assume any liability for incorrect information and their consequences.
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Table of Contents
1 Introduction 5
2 Components 6
2.1 Battery 6
2.2 Resistors 6
2.3 Ceramics Capacitator 7
2.4 Electrolyte Capacitator 7
2.5 LED 8
2.6 Transistor 9
2.7 Diode 10
2.8 Integrated Circuit (IC) 11
3 Soldering Basics 12
3.1 What is Soldering? 12
3.2 The Soldering Iron 12
3.3 Soldering Equipment 13
3.4 Too Hot and too Cold Solder Points 16
3.5 The Right Tools 17
3.6 Before Starting Soldering 18
4 Soldering 19
4.1 Tinning Stranded Wire 19
4.2 Soldering Together Wires 20
4.3 Preparing Components 20
4.4 Soldering Wire Bridges to Strip Grid 21
4.5 Soldering Wire Bridges to a Point Grid 23
4.6 Soldering Wire Bridges to a Point Grid - Version 2 24
4.7 De-soldering Lateral Wire Bridges 25
4.8 De-soldering Soldered-In Wire Bridges 26
4.9 Simple LED Circuit: Preparations 27
4.10 Simple LED Circuit 28
4.11 Soldering SMD Diode 32
4.12 Soldering SMD Operational Amplifier 34
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4.13 Soldering Components Close Together 37
4.14 Soldering Sensitive Components 39
4.15 Removing Short Circuits Caused in Soldering 40
4.16 Completing Transistor Circuit 42
4.17 Checking Circuit and Shortening Excessive Lengths 43
4.18 De-soldering Components with Several Legs 44
4.19 The Masterpiece 46
4.20 Other Circuits 47
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1 Introduction
Specialist trade offers innumerable electronics circuit construction kits that you can solder
together yourself. If you want to work with them, you should know how to handle a sol-
dering iron.
This learning package helps discovering the secrets of soldering step by step. In a series of
subsequent exercises, you will learn how to solder various components and how to de-
velop and build complete circuits. Before starting on the actual work, the learning pack-
age will also teach you all the basics required for successful soldering.
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2 Components
2.1 Battery
The battery must be connected to any circuit in the correct polarity. The required battery
clip has a red (plus) and black (minus) connection wire each. Both wires must be sol-
dered on according to the required polarity.
Figure 1: Battery circuit symbol
2.2 Resistors
Resistors are some of the simplest electronic components. They are labelled in a colour
code consisting of three rings and to be read from the edge to the centre. A fourth ring,
offset slightly, indicates the component tolerance. The impedance value is indicated in
Ohm (O).
Figure 2: Impedance colour code
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Figure 3: Resistor
Figure 4: Resistor circuit symbol
2.3 Ceramics Capacitator
The capacitator is another important electronics component. It is available in two ver-
sions. The simpler version is the small, round and flat ceramics capacitator. It is secured
against polarity reversal. Capacities are indicated in Farad (F). The ceramics capacitator is
labelled in a number code. 104 corresponds to 10 x 104, i.e. 100,000 Picofarad (pF).
Figure 5: Ceramics capacitator circuit symbol
Figure 6: Ceramics capacitator
2.4 Electrolyte Capacitator
The larger electrolyte capacitator has a cylindrical body and must be installed in the cor-
rect polarity. The minus pole is marked with a white lateral stripe and has a shorter con-
nection wire. If the Elko is installed in the wrong polarity, it will be destroyed. It is
labelled in plain text.
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Figure 7: Electrolyte capacitator circuit symbol
Figure 8: The electrolyte capacitator must be installed in the correct polarity.
2.5 LED
Always observe polarity when installing a light diode. The LED has two connection wires
of different lengths. The longer one is the plus pole. It is called anode (A). The minus pole,
the cathode (K), has the shorter wire.
The polarities are also visible inside the LED. The minus pole has the shape of a large tri-
angle. The plus pole is only very small.
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Figure 9: An LED must be installed in the correct polarity.
Figure 10: LED circuit symbol
2.6 Transistor
The transistor amplifies small currents. Its connections are called emitter (E), basis (B)
and collector (C). The cylindrical casing is flattened on one side. The type designation is
printed on here. Looking at the transistor so that the connections point down and the
label can be read, the emitter is on the left side. The basis is at the centre.
Figure 11: Transistor with view of the flattened side.
Connections from the left to the right: Emitter (E), basis (B) and collector (C).
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Figure 12: NPN transistor circuit symbol
2.7 Diode
A diode lets current through in one direction only and blocks it in the counter-direction. It
can be imagined like a check valve from a water installation.
Conventional diodes are cylindrical like resistors. Their minus pole (cathode) is marked
with a dash.
SMD diodes are very small. They are labelled on top with a short designation consisting
of a letter and a number. The left end of the label marks the cathode (–), the right one the
anode (+).
Figure 13: Diode circuit symbol
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Figure 14: MD diodes are very small.
2.8 Integrated Circuit (IC)
The learning package contains an IC type LM358 in SMD build. The installation direction
must be observed when soldering on the IC. Polarity reversal must be avoided. It may de-
stroy the component. PIN 1 is marked by a point at the top of the casing.
Figure 15: PIN assignment of the SMD-IC LM358
Figure 16: At the SMD-IC, PIN 1 is marked by a point at the top of the casing.
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3 Soldering Basics
3.1 What is Soldering?
In electrical engineering, soldering is one of the basic ways of establishing connections.
Soldering creates an electrically conductive connection that cannot be disconnected.
Using a melted metal binding agent (solder), soldering connects two metal work-pieces -
e.g. a PCB onto which an electrical component is soldered. The solder has a lower melting
point than the metals to be connected.
Soldering is performed at temperatures of around 340 °C. The metals to be connected do
not melt. The solder acts as a kind of adhesive. However, so-called mixed crystals form at
the transfer zone between metal and solder, forming a diffusion zone. The solder does not
just adhere to the metals to be connected, but enters into a crystalline connection with
them.
Using a looped solder connection, the mix crystal layer, that is, the area where solder and
each of the metals melt together, has a width of approx. 0.5 µm. If this transfer layer is too
large, the solder connection becomes brittle and porous. If the transfer layer is too thin,
the parts that were soldered together may disconnect again once you lift them up.
3.2 The Soldering Iron
Soldering irons are available in different designs and sizes. They must match the task to
be performed. For electronics applications, you need a soldering iron with a small solder-
ing tip and low connection power. Both ensures that you will be able to solder small com-
ponents well without heating them excessively.
Fine soldering iron
Fine soldering irons have a power consumption between 8 and 25 Watt (W). They are
best for soldering sensitive electronic components. A fine soldering iron is recommended
if you are dealing with small solder points.
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Universal soldering iron
Universal soldering irons are slightly larger. Their power consumption is between 20 and
40 W. They are particularly suitable for hobby and craft use. They can also be used well
for electronics soldering. They are also the first choice if you want to assemble simple to
medium electronics kits.
Standard soldering iron
Standard soldering irons consume about 50 to 150 W and are already too large for elec-
tronics hobbyists and handicrafts enthusiasts. They have an angled soldering tip. With
their large dimensions and high heat output, they are not suitable for fine soldering work.
They are therefore not suitable for electronics soldering.
Soldering stations
Soldering stations are meant for stationary use in a workshop. They consist of the actual
soldering iron and a control unit where the soldering temperature can be set between
about 150 °C and 450 °C. These are fine soldering irons optimised for electronics use.
Therefore, soldering stations are mainly found in advanced electronics enthusiast work-
shops.
3.3 Soldering Equipment
Soldering will always require some solder. Tin solders are used the most often. Their
melting point is at 330 °C. When heated, the tin solder first changes from firm to mushy
condition, then melts.
Several solders still contain lead, even though leaded solders are no longer permitted for
use in the electronics area since 1 July 2006. Lead is dangerous to health and pollutes the
environment. Nevertheless, leaded solders are still permissible for private use and lim-
ited industrial uses.
In addition to the soldering iron, you will also need some equipment to solder. One piece
of equipment is the soldering iron stand. It is used to securely deposit the hot soldering
iron. It consists of a stable base and a solid metal coil into which the soldering iron is put
when not in use.
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The solder sponge is one of the most important, as well as the most simple accessories of
the soldering iron. It is moistened with water and placed in the intended dish of the sol-
dering iron holder. Then you can clean the soldering tip by wiping off contaminations or
excess solder.
A fine mechanics’ clamp makes soldering easier. It can hold the PCB and keep it in the
position where work is easiest for you. This will leave your hands free for the soldering
iron and solder.
A de-soldering pump can be practical for de-soldering components. It looks like an over-
sized ballpoint pen. It is used to extract excess solder from the solder point.
Alternatively, you may also use de-soldering wires. They consist of thin, braided strands
and are available at different widths.
An electronics pliers set to bend components in shape and shorten excess lengths of con-
nection wires is also recommended. Pincers can be helpful for small SMD components, as
can a magnifying glass.
Figure 17: 15-W fine soldering iron by Conrad Electronic (order no: 588539-62);
this makes electronics soldering easiest.
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Figure 18: Stable soldering iron stand with solder sponge for cleaning contaminated soldering tips
Figure 19: The fine mechanics’ clamp can be used to hold and comfortably solder PCBs.
Figure 20: Soldering aids with magnifying glasses also hold the PCB.
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Figure 21: De-soldering pump (order no.: 588502-62) to remove excessive solder
3.4 Too Hot and too Cold Solder Points
Perfect soldering can be recognised by its nice gloss. A cold soldering point looks some-
what matte and often has a lumpy surface. Defective solder points can also be recognised
if the small solder cone around the component connection is missing or hardly there. Cold
solder points have only low mechanical resistance. If you jiggle a component a little, the
connections within the solder cone may come loose, and it will only loosely be stuck in it.
Cold solder points occur if you did not sufficiently heat the solder point and solder. This
may happen if soldering is done very fast or if the soldering iron does not provide enough
power for larger soldering work. Cold solder points will break open even at very small vi-
brations.
Bad solder points may also result from high temperatures. The high soldering temperature
will cause faster oxidation of the components to be connected. A typical sign for the sol-
der temperature being too high is also so-called
whisker-formation . Whiskers are solder
residue that stands out of the solder point like thin protrusions and that may cause short
circuit.
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Figure 22: Correct solder points are glossy with a smooth surface.
3.5 The Right Tools
Soldering is best done with suitable equipment. We recommend the 15-W solder iron
starter set available from Conrad Electronic (order: no.: 588292-62). In addition to a 15-W
soldering iron, it comprises two soldering tips, solder, a deposit stand and a de-soldering
pump.
If you only need the soldering iron, we recommend the 15-W hand soldering iron, also
available from Conrad Electronic (order no.: 588539-62) and the de-soldering pump (order
no.: 588502-62).
Before starting with your soldering practice, prepare an appropriate surface This may be a
strip of flooring or stable cardboard.
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Figure 23: Starter solder sets (Order no.: 588292-62) contain everything one needs to learn how to solder.
3.6 Before Starting Soldering
Proper soldering is only possible if you keep the soldering tip clean at all times. Regularly
wipe it off with a moist sponge. This removes excess solder from the soldering tip.
Figure 24: Over time, solder collects at the soldering tip, which makes soldering considerably more difficult.
Figure 25: Therefore, contaminations need to be wiped off regularly with the moist sponge.
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4 Soldering
4.1 Tinning Stranded Wire
Fine-stranded wires are hard to solder because their strands go in all directions when sol-
dering. The battery clip wire ends show how perfectly tinned wires should look. Cut off
the tinned parts and strip about 5 mm of the wires. Then twist the strands evenly be-
tween your fingers. This makes the wire more stable.
Heat one wire end with the soldering iron and add a little solder. Heating melts the solder
immediately and covers the wire piece with a solder film. Don’t take too much time when
tinning, because extended heating will also cause the wire insulation to melt.
Figure 26: First twist the strands between your fingers.
Figure 27: The twisted wire must be heated and some solder added, which melts at once.
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4.2 Soldering Together Wires
For both wires to keep their position during soldering and you to have both hands free to
work, clamp them into an electronics clamp and put them in position. Then use the sol-
dering tip to heat both wire ends evenly. Now add the solder by moving it to the heated
solder point. This solder process also should be completed quickly to keep the wire from
heating up too much and the insulation from being damaged.
Figure 28: Since the insulation melts quickly, the wires must be soldered together quickly.
4.3 Preparing Components
A circuit soldered together yourself should not only work, it should also be well struc-
tured. This facilitates later modification and conversion, as well as repairs to the circuit.
A good structure also means that you prepare the components to be soldered by bending
them in shape with a round electronics pliers. The resistor’s connections must be bent at
a right angle. Consider the hole distance on the PCB so that the component can be
pushed into the bores well. The connections must not be bent directly at the casing edge.
Danger of destruction. Apply the pliers at the resistor so that it touches the
casing. Then bend the wire end pointing away from the pliers by 90 degrees. Proceed ac-
cordingly with the second connection. Both angled wires must point in the same direction
now.
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