Transcript Electronics Merit Badge

Electronics Merit Badge
Old Colony Council
Seven Rivers District Merit Badge University
March 2007
Joe Mulcahey
Rev. K, 01MAR07
Name ____________________
1
Based on the Electronics Merit Badge class taught at the 2005 National Jamboree
Electronics Merit Badge Class
Outline
Class 1
March 3
Safety
Electricity & Electronics Introduction
Circuit Diagrams & Schematics
Solving Circuit Problems using Ohm’s Law
Class 2
March 10
Test Equipment Demos
Job Opportunities in Electronics
Class 3
March 24
Proper Soldering Techniques
Kit Assembly
2
Safety:
Effects Of Electric Shock
AC - 60 Hz
0-1
1-4
4-21
21-40
40-100
Over 100
Current (milliamperes)
DC
Effect
0-4
Perception
4-15
Surprise
15-80
Reflex Action
80-160
Muscular
Inhibition
160-300
Respiratory Block
Over 300
Usually Fatal
3
Safety: Protective Measures
Measure
0-<50V
50-<500V
500+V
1) Enclosures, Guards,
Optional*
Required
Required
Barriers
2) Interlocks
Optional
Optional***
Required
3) Warning Signs
O-Caution* R-Caution
R-Danger
4) Shorting Rods
Optional*
Optional
Required
5) Remote Circuit
Optional
Optional
Required**
Adjustment
6) Automatic Bleed
Optional*
Required
Required
Down
* Required for high current (>25 amperes).
**At or above 300V.
*** Required at point of operation.
4
Safety: Capacitors
• Shall have their terminals wired together if they
are identified as subject to recharge hazards
(dielectric absorption) and when loose or
connected to an idle test configuration without
integral bleeders.
• If capable of an impulse discharge of 0.25 joule or
more, terminals must be grounded when the
system is idle - including when in storage.
• In general capacitors with a metal shell, voltage
rating greater than 50 volts, and a volume greater
than 8 cubic inches most likely present an
electric shock hazard.
5
Introduction to Electronics
•Electrical and Electronics Engineering are both career fields that are
involved with Electronics Technology. Electrical engineers specializing in
power work with motors and generators, and design transmission lines
and power plants. EEs specializing in electronics deal with
communications, such as radio, television and telephony, radar and
digital & analog circuit technologies. All engineers draw from the
fundamentals of science and mathematics. They design and work with
electrical, electronic, electro-optical, and electromechanical devices,
circuits, and systems.
•They collaborate with other professionals in developing sophisticated
software tools that support design, verification, and testing. Electrical
engineering is a discipline that integrates many other disciplines, such as
physics, chemistry, mathematics, computer software and hardware, solidstate electronics, communications, electromagnetics and optics, signals
and signal processing, systems science, reliability, engineering
economics, and manufacturing.
•In order to Learn about Electronics, we must first start by gaining an
understanding of what electricity is, both AC (Alternating Current) and DC
(Direct Current).
6
Electricity
Typical House
Electricity
Two types of Electricity:
AC = Alternating Current
DC = Direct Current
(VRMS =2 x Vpeak)
AC = Alternating Current
Steam
Engine
Electric
Generator
170 Volts
Peak
RMS 120 VAC
Ground
Produces
AC voltage
-170 Volts
Peak
60 cycles per second
DC = Direct Current
+ 12.0 Volts
Flashlight
1.5 Volt
Battery
1 Car Battery
+ 6.0 Volts
4 Battery
+ 3.0 Volts
+ 1.5 Volts
2 Battery
1 Battery
Ground
or 0 volts
7
Electric Generation Plants
Coal, Gas, Oil-fired Steam Power Plant
Wind Power Plant
Hydro (Water) Power Plant
8
Gas Turbine Combined Cycle Plant
Circuit Breaker / Fuses
Electricity from the transformer connect first through the electric meter
then through the breaker box to protect the house from overload
or short conditions. A breaker box can either be a fuse or resettable breaker.
The breaker box routes either 240 VAC or 120 VAC electricity to different places.
240 VAC
120 VAC
240 VAC
Electric Meter
Electric
Breaker
Box
120
VAC
Stove
9
Circuit Breaker / Fuses
Fuses
A Fuse is like a light bulb.
It will pass electricity until
it is overloaded, then the metal
fuse link will burn open.
Circuit Breaker
A circuit breaker Is like a light switch.
If it is overloaded the switch will
overheat and click open. When
it cools down the switch can be reset.
If Fuses or Circuit Breakers are overloaded or shorted they will open
120 VAC
120 VAC
ON
OFF
_____
ON
OFF
________
What’s the difference?
_______
_______
10
Home Appliances
That run on AC Power
What are some other common
items that use AC Voltage in Homes
1) ______________
Microwave
TV
2) ______________
3) ______________
4) ______________
5) ______________
Sewing Machine
6) ______________
Stereo
Computer
11
House Wiring
A house is wired with heavy gauge wire to handle 120 Volts AC in order
to power high wattage devices that are found in a home. A circuit breaker
or fuse is used to protect the wire from getting too hot, and possibly
starting a fire. House Items are rated in wattage, but the fuse is in amps.
How do we know if we are going to overload our fuse or breaker box?
120 VAC
120 VAC
Meter
Circuit
Breaker
or
Fuse
Box
Four outlets
on one breaker.
20 A
20 A
20 A
20 A
Microwave
600 Watts
Watts = Volts * amps
Amps = Watts
Volts
Refrig
400 Watts
Toaster
TV
1200 Watts 300 Watts
Determine if the circuit breaker is overloaded. Calculate total power
Refrig.
Toaster
TV
Microwave
Power = ________
Amps = watts
volts
+
=
________ + ________ + _______ =
_______
=
_______ amps
________ Watts
Overload Yes or No ________
12
Direct Current
Glass of
Water has
Force called
pressure
Carbon
Rod
Gel
Insulator
Zinc
Casing
Charged
Battery
1.5 volts
Flashlight
+
+
+
+
+
+
--- - -
Empty Glass
Has no Force
-
-
------
Switch
-
-
Current Flow
Electrons
Battery works
from a chemical
reaction between
the carbon rod
and zinc case
+
+
+
--
+
--+
+
+
--+
+ - -
-+--
Dis-Charged
Battery
No Voltage
Voltage is the quantity of electrical force Measured in Volts
Current is the flow of electrons Measured in Amps
DC Stands for Direct Current
13
DC is current flowing in one direction
Direct Current
Battery Types
C
D
Cell
Flashlight
1.5 volts
1 Amp
Cell
1.5 volts
1.5 volts
4
Amp
Hours
2
Amp
Hours
AA
Cell
AAA
Cell
1.5 volts
0.5
Amp
Hours
If a flashlight draws 0.1 Amp, how long will each battery last?
Time = Amp Hours / Load in Amps
D cell
= Amp Hours = _____ = _______ hours
Amps
C cell
= Amp Hours = _____ = _______ hours
Amps
AA cell = Amp Hours = _____ = ________ hours
Amps
AAA cell = Amp Hours = _____ = ________ hours
Amps
0.2
Amp
Hours
14
Direct Current
Cost of Batteries for the Same Output
D Cell
$ 1.50
4
Amp
Hours
8 – AA Cell
8x$.65 = $5.20
Same
Same
2 - C Cell
as 2x$1.10 = $2.20 as
=
2
2
Amp Amp
Hours Hours
.5
.5
=
.5
.5
.5
8 x .5 = 4
Amp
Hours
.5
.5
.5
Amp
Hours
Same
as
=
20 – AAA Cell
20 x $.45 = $ 9.00
20 X .2 = 4
Amp
Hours
The more Batteries
The more waste
15
Battery Types
•Zinc-carbon battery - Also known as a standard carbon battery, zinc-carbon
chemistry is used in all inexpensive AA, C and D dry-cell batteries. The electrodes
are zinc and carbon, with an acidic paste between them that serves as the
electrolyte.
•Alkaline battery - Used in common Duracell and Energizer batteries, the electrodes
are zinc and manganese-oxide, with an alkaline electrolyte.
•Lithium photo battery - Lithium, lithium-iodide and lead-iodide are used in cameras
because of their ability to supply power surges
•Lead-acid battery - Used in automobiles, the electrodes are made of lead and leadoxide with a strong acidic electrolyte (rechargeable).
•Nickel-cadmium battery - The electrodes are nickel-hydroxide and cadmium, with
potassium-hydroxide as the electrolyte (rechargeable).
•Nickel-metal hydride battery - This battery is rapidly replacing nickel-cadmium
because it does not suffer from the memory effect that nickel-cadmiums do
(rechargeable).
•Lithium-ion battery - With a very good power-to-weight ratio, this is often found in
high-end laptop and cell phones (rechargeable).
•Zinc-air battery - This battery is lightweight and rechargeable.
•Zinc-mercury oxide battery - This is often used in hearing-aids.
•Silver-zinc battery - This is used in aeronautical applications because the power-toweight ratio is good.
•Metal-chloride battery - This is used in electric vehicles
16
Flashlight Diagram
Copper Strip
(-) Conductor
Tension
Spring
(-)
Battery
Contact
As slide switch
moves forward,
Copper strip makes
contact with bulb
base ring, thus
completing circuit.
Slide
Switch
Bulb base
ring
extender
Battery
Cells
Lens
Bulb
Deflector
Bezel
17
Direct Current
Car Battery System
Car Battery consist of six 2 Volt cells. How much total Voltage?
2v + 2v + 2v + 2v + 2v + 2v = _________Volts
Horn
What are some of the electrical items in a car?
18
DC Circuit Wiring
Build three different DC circuits using the test box
Switch
Light
Buzzer
Power
Supply
Buzzer
Power
Supply
Buzzer
Power
Supply
Wire to turn Buzzer On/Off
Switch
Light
Wire to turn Light On/Off
Switch
Light
Wire to turn Light On in one
direction and buzzer on in other
direction
19
Direct Current
Draw 3 different wiring test circuits
Switch
Light
Fuse
Power
+ 12
Buzzer
20
Direct Current
Circuit to Switch Buzzer On / Off - Draw the rest of the wires
Switch
Buzzer On
Light
Fuse
Power
+ 12
Buzzer
21
Direct Current
Draw Circuit to Switch Light On / Off
Switch
Light On
Light
Fuse
Power
+ 12
Buzzer
22
Direct Current
Draw Circuit to Turn Buzzer on in one Direction and Light in other Direction
Switch
Light On
Light
Buzzer On
Fuse
Power
+ 12
Buzzer
23
Electronic Components
Batteries
In volts
Resistor
In Ohms
+
Inductor or Coil
In henries
Microphone
Outputs
voltage
Power Supply
Outputs Volts
120V
AC In
DC
volts
Out
Potentiometer
Variable
Resistor
Transformer
Input voltage
Speaker
Input voltage
Isolated
Capacitors
In Farads
Step
Down
+
Step
Up
24
Electronic Components
Transistor
Switch
Electronic Switch. Emitter, Base
Normally Open (n.o.)
& Collector terminals. Small
Normally Closed (n.c.)
current (B-E) controls a larger
one (C-E). Made of N (negative)
n.c.
n.o.
and P (positive) sections
Slide Switch
Can connect the center
Pole to one of two
Throws (SPDT)
NPN
(“Never
Points iN”)
PNP
(“Points iN
Proudly”)
Bonus Question: Which
type is the Transistor on the
Electronics Merit Badge?
Diode
PN junction. Current
flows in direction of
arrow only
Anode (P)
Cathode (N)
LED
Light
Emitting
Diode
Meters
Current Meter
Voltage Meter
Resistance Meter
25
Electronic Circuits:
Ohms Law
Water Flow
Bucket Stores Water
Bucket
Current Flow
Current Meter
measures Amps
Battery Stores
Energy
1 Gallon
Valve restricts
flow of water
Flow Meter
Water Wheel
Gallons/hour
Valve restricts water flow
Volt Meter
Measures
1.5 Volts
Switch
Current
= 1 amp
Resistor
restricts current flow
Light dimmer
Ground or 0 volts
Voltage measured in volts (Symbol = V)
Current measured in Amps (Symbol = I)
Resistance measured in Ohms (Symbol = Ω )
Formula
Resistance = Voltage
Current
Voltage = Resistance X Current
Current = Voltage
Resistance
26
Ohm’s Law Pie Chart
27
Where Did the Names of the Electrical
Parameters Come From?
•Volts: Count Alessandro Volta (1745-1827), Italian Scientist
•Ohms: Georg Simon Ohm (1787-1854), German Physicist
•Amps: André-Marie Ampère (1775-1836), French Physicist
•Watts: James Watt (1736-1819), British Engineer
•Farads: Michael Faraday (1791-1867), British Physicist
•Henrys: Joseph Henry (1797-1878), American Physicist
•Other Units:
•Coulomb, Gauss, Joule, Tesla and of course Smoot
28
Smoot? What’s A Smoot?
Smoot: A humorous unit of distance invented in
1958 by a fraternity at the Massachusetts
Institute of Technology. The fraternity pledges of
Lambda Chi Alpha measured the length of
Harvard Bridge using pledge Oliver R. Smoot
('62). According to Smoot himself, the bridge
turned out to be 364.4 smoots long "plus
epsilon," but this has been recorded as 364.4
smoots "plus an ear." The bridge is still marked
in smoots. Proposals to change the definition of
the unit by remeasuring it with Smoot's son
Steve (MIT '89) or daughter Sherry ('99) were
rebuffed. One smoot equals 67 inches (170.18
centimeters). Oliver Smoot became an attorney
but continued his interest in standards and
measurement. He is a past Chairman of the
Board of Directors of ANSI, the American
National Standards Institute, and currently he is
the President of the International Organization
for Standardization (ISO).
29
Electronic Components: Resistors
Pipe
Resistor
1” Pipe
Resistor restricts
flow of current.
Resistors are made of
carbon or wire.
Smaller pipe
1/2” Pipe restricts
flow of fluids
Valve
Variable
Resistor is a
Potentiometer
Valve restricts
flow of fluids
This could be used to control volume in a radio
Resistance measured in Ohms (Symbol = Ω)
2” pipe
1” pipe
¾” pipe
½” pipe
¼” pipe
The smaller the
pipe the more
restriction of flow
The larger the
resistor value
the more
restriction
to current flow
1 ohm
10 ohm
100 ohm
1,000 ohm =
1 K ohm
10,000 ohm = 10 K ohm
100,000 ohm = 100 K ohm
1,000,000 ohm =
1 M30ohm
Resistor Color Rings
A Resistor Value is determined
by its color band and is measured in ohms
First Ring is First number / Closest to edge of resistor
Second Ring is second number
Third Ring is number of zero’s
Fourth Ring is tolerance 1% or 5% or 10% etc.
Resistor Color Code Values
First Ring
Black = 0
Brown = 1
Red
=2
Orange = 3
Yellow = 4
Green = 5
Blue
=6
Violet = 7
Gray = 8
White = 9
Second Ring
Black = 0
Brown = 1
Red
=2
Orange = 3
Yellow = 4
Green = 5
Blue
=6
Violet = 7
Gray
=8
White = 9
Third Ring Multiplier
Silver =
X
.01
Gold =
X
.1
Black =
X
1
Brown =
X
10
Red
=2= X
100
Orange = 3 = X
1,000
Yellow = 4 = X
10,000
Green = 5 = X
100,000
Blue
= 6 = X 1,000,000
Violet = 7 = X 10,000,000
Fourth Ring
Brown = +/- 1%
Red = +/- 2%
Gold = +/- 5%
Silver = +/- 10%
None = +/- 20%
31
G-Rated Resistor Color Code Mnemonics
Black Brown Red Orange Yellow Green Blue Violet Gray White (Gold Silver None)
0
1
2
3
4
5
6
7
8
9
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Big Brown Rabbits Often Yield Great Big Vocal Groans When Gingerly Slapped
Big Bears Run Over Your Gladiola Bed Vexing Garden Worms
Black Bears Run Over Yellow Grass, But Vultures Glide over Water
Better Be Right Or Your Great Big Venture Goes West
Bye Bye Rosie Off You Go to Birmingham Via Great Western
Black Bart's Rambler Over Yonder Gave Bad Vibes Going West
Bright Boys Rave Over Young Girls But Veto Getting Wed
Big Boys Race Our Young Girls Behind Victory Garden Walls
Big Boys Race Our Young Girls But Violet Generally Wins
Black Birds Ruin Our Yellow Grain, Butchering Very Good Wheat
Billy Brown Ran Over a Yodeling Goat Because Violet's Granny Was Grumpy
Bad Betty Runs Over Your Garden But Violet Gray Won't
Billy Brown Revives On Your Gin, But Values Good Whisky
Better Be Ready, Or Your Great Big Venture Goes West
Black Beetles Running On Your Garden Bring Very Good Weather
Bowling Balls Roll Over Your Grandpa But Victim Gets Well
Batman Bests Robin On Yonder Gotham Bridge; Very Good, Will Get Superman Next!
Badly Burnt Resistors On Your Ground Bus Void General Warrantee
Big Bart Rides Over Your Grave Blasting Violent Guns Wildly
Bad Borg Raid Our Young Galaxy Before Vaporizing Good Walter
32
Resistor Value Examples
First Ring is units
Second Ring is Ten
Third Ring is number of zero’s
Example of Color Rings
First Ring
Red
=2
Black
=0
Second Ring
Red = 2
Red = 2
Third Ring
Red
= X 100
Brown = X 10
Ring
Black = 0
Brown = 1
Red
=2
Orange = 3
Yellow = 4
Green = 5
Blue
=6
Violet = 7
Gray = 8
White = 9
= 2200 ohms
= 020 ohms
Test of Color Rings
First Ring
Brown = ____
Second Ring
Green = ____
Third Ring
Brown = _____
= ______ ohms
Green
Red
Yellow
= ______ ohms
= ____
= ____
= _____
33
Electronic Components
Voltage Storage Devices
Bucket
Batteries
Sold already
charged. Some may
be recharged
Different size buckets of
water with the same
height and with a ¼”
hole will take different
amounts of time to empty
1 gallon = 1 hour
2 gallon = 2 hours
5 gallon = 5 hours
10 gallon = 10 hours
Capacitors
Most batteries are
1.5 Volts per cell.
AAA
AA
C
D
= .2 amp hours
= .5 amp hours
= 1 amp hour
= 4 amp hours
Stores small amounts
of Voltage charge
Measured in Farads
Un-Polarized
Polarized
1f
= 1.0 Farad
10 mf = .01 Farad
1,000 mf = .001 Farad
100 mf = .0001 Farad
10 mf
= .00001 Farad
1 mf
= .000001 Farad
.1 mf
= .0000001
.01 mf = .00000001
.001 mf = .000000001
100 pf = .0000000001
10 pf
= .00000000001
1 pf
= .000000000001
34
Transistors
A Transistor is an Electronic Switch
Transistor
NPN
Switch
Transistor come in
different sizes depending
on the amount of current
and voltage required
Transistor Switch Circuit
Mechanical Switch Circuit
Light
12 Volt
Battery
Switch open
Light off = 0
12 Volt
Battery
NPN Transistor
Switch close
Light on = 1
Computer can
send a signal to turn
on the transistor which
then turns on the light
35
Integrated Circuits
An integrated circuit (IC) consists of multiple transistors. The number of transistors
can vary from just a few (circuits shown below), to several hundred million that are
in a Pentium microprocessor.
6 Transistors in one IC
This IC has 6 inverters
An inverter contains
6 Transistors = 36 total
Functions
Inverters
Gates
Flip flops
Counters
Memory
MPU
Watch ICs
Calculators ICs
Microwave Timer ICs
Radio ICs
Dialer ICs
Car Controller ICs
36
Moore’s Law
Transistors
Capacity
PowerPC/Pentium
1000M
PowerPC/Pentium
100M
PowerPC/Pentium
Motorola / Intel
10M
68040/80486
Every 18 months CPU’s
double in density and
performance, while still
holding prices the same
68030/80386
1M
68020/80286
100K
68000/80186
10K
6800/8080
Apple IIE
Power
Mac
Mac
1K
IBM/Intel
8080
1970
1975
1980
1985
IBM
386
1990
IBM
486
1995
Year of Introduction
iMac
IBM/Intel
Pentium
2000
2005
2010
37
Microprocessor Integrated Circuit:
60,000 Transistors
38
Test Equipment
•Power Supply
•Power Equipment or Components for Test
•Volt-Ohm Meter (VOM)
•Check AC & DC Voltages, Resistance, Opens/Shorts
•May also Measure Capacitance, Inductance, Gain, etc.
•Oscilloscope
•Graphs one Voltage vs. Time or vs. another Voltage
•Radio Equipment Testing
•Signal Generator
•Receiver
•Power Meter
•Spectrum Analyzer
•Graphs Voltage versus Frequency
•Network Analyzer
•Field Strength Meter
39
Electronics Jobs and
Education & Certification Required
•Electronics Technician (Computers, Cable TV, Repair, etc.)
•6 months to 2 years of Electronics School during or after High School
•Microsoft, other Certifications Available
•Entry-Level Design Engineer
•4-year Bachelor of Science in Electrical Engineering Degree
•Senior-Level Design Engineer, Engineering Manager
•4-year BSEE Degree, 2-year MSEE Degree
•Some Engineering Positions Require State Registration (P.E.)
•University, R&D Laboratory Researcher
•Ph. D. or Sc. D. Degree in Physics or EE
Joseph K. Mulcahey, P.E.
Engineering Fellow
978.440.3291 office, 978.440.2874 fax
508.259.5372 cell
[email protected]
40
Graduating Engineers by Type
From the American Society for
Engineering Education
(http://www.asee.org)
41
US BS Engineering Graduates By School, 2004-05
(Source: ASEE)
Rank
School
1
Pennsylvania State University
2
# BS Eng. Degrees
Rank
School
# BS Eng. Degrees
1,396
26
University of California, Davis
600
Georgia Institute of Technology
1,372
27
Massachusetts Institute of Technology
593
3
Purdue University
1,261
28
University of Colorado, Boulder
589
4
North Carolina State University
1,240
29
Rensselaer Polytechnic Institute
585
5
University Of Illinois, Urbana-Champaign
1,198
30
University of Puerto Rico, Mayaguez
564
6
University of Michigan
1,127
31
Drexel University
551
7
Virginia Tech
1,098
32
Auburn University
517
8
Texas A&M University
1,044
33
Clemson University
515
9
Ohio State University
892
34
SUNY, Buffalo
514
10
University of California, San Diego
883
34
Oregon State University
514
11
University of Florida
882
36
Colorado School of Mines
506
12
Iowa State University
868
37
University of Missouri, Rolla
493
13
University of Texas, Austin
865
38
University of Arizona
479
14
University of Minnesota, Twin Cities
818
39
California State Polytechnic U., Pomona
478
15
University of California, Berkeley
776
40
University of California, Irvine
476
16
California Polytechnic State University
706
41
SUNY, Stony Brook
469
17
Cornell University
688
42
San Jose State University
453
18
Arizona State University
637
43
Kansas State University
440
19
University of Wisconsin, Madison
634
44
Rutgers University
435
20
Michigan Technological University
627
45
University of Virginia
427
21
University of Washington
624
46
Louisiana State University
413
22
University of California, Los Angeles
615
47
Stanford University
388
23
Michigan State University
614
48
Polytechnic University of Puerto Rico
387
24
University of Central Florida
607
49
University of South Florida
25
University of Maryland, College Park
605
50
University of Utah
385
42
384
US News & World Report 2007
US Undergraduate Engineering School Rankings
Rank
School
1
Massachusetts Institute of Technology (MA)
2
University of California, Berkeley (CA)
2
Stanford University (CA)
4
California Institute of Technology (CA)
4
University Of Illinois, Urbana-Champaign (IL)
6
Georgia Institute of Technology (GA)
6
University of Michigan, Ann Arbor (MI)
8
Carnegie Mellon University (PA)
8
Purdue University (IN)
10
Cornell University (NY)
43
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45
Soldering
Safety Note: A Soldering Iron gets hotter than 300 F. Do not touch
the soldering iron’s metal parts or you will receive a third degree burn
A good solder joint depends on the following:
1) Solder iron must have a clean, well-tinned tip
2) Parts to be soldered must be clean
3) There must be a sound mechanical joint
4) Parts to be soldered must be well heated before applying solder
5) Wait approx. 5 seconds after soldering to allow strong mechanical
joint to form
46
Soldering – Heating Junction
Iron
Iron
Wire
PC Board
Right
Solder melts at 310° F. The way
wire and PC (Printed Circuit)
board must be the same
temperature for the solder to
melt on both items.
Place soldering iron so that it touches both the PC
board and wire. The heat from the soldering iron
will transfer to the PC board and wire at the same
time.
Wire
PC Board
Wrong
way
Iron
Wire
PC Board
47
Soldering – Applying Solder
Wrong
way
After 3 seconds place the
solder on the tip of the
iron, the wire and the PC
board all together.
The solder should flow to
everything making a
good connection.
Wire
Iron
Solder
When the board and wire are hot
enough the solder will flow and
create a cone shape. If
the board is not hot enough the
solder will be rounded on the
board creating somewhat
of a ball. The finishing solder
should also be shiny. Clip extra
wire at board level.
PC Board
Wire
Iron
Wire
Right
way
PC Board
Solder
PC Board
48
Un-Soldering
1. Use pliers to hold the component next to the lead to be
unsoldered (If the lead is held with the pliers it will draw heat
from the lead)
2. Apply soldering iron tip to PC board and wire
3. Either use solder wick or solder sucker to draw solder off the
board, or simply pull wire from PC board when hot
4. The soldering iron will damage electronic components if left on
device for greater than 15 seconds, so work quickly
5. Sometimes it helps to put more solder on the solder joint to
improve the thermal conductivity
6. Clean the soldering iron tip and keep it shiny
49
Un-Soldering
Iron
With pliers, hold device
close to lead that is to be
unsoldered. As heat is
applied from soldering
iron, pull with pliers.
With one side out, do the
same on other side.
Wire
PC Board
Iron
Pliers
PC Board
50
Kit Assembly
1) Place components into PC board in the order recommended on instruction
sheet
2) When components are placed into PC board, bend leads out slightly to
keep parts from falling out, when the PC board is turned over for soldering.
3) Follow instructions as to proper orientation of components.
PC Board
Wrong
Clip wire at board
Correct
Red +
Black
LED
Note Flat Edge
51