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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 om En gi pu ne e r te r S in g ci en Bu ce H si el ne at h ss Sc ie nc H Sc e s om ie n e Ec ces on om ic Ag s C r om ic ul m un ture ic at io H um ns an i Ed ties (2 00 uc 7 at M io in n .W ag e) C Annual Salary, $ Starting Salaries Jobweb.com Broad Category Offers to 2005-06 Graduates 50,000 45,000 40,000 35,000 30,000 25,000 20,000 15,000 10,000 5,000 0 44 he m ic al E at ng er . ia EE , C ls E ng om . m C . En om g. pu M t er et al En lu g. rg i ca M ec lE ha ng ni . ca lE Sy n st em g. s In En du g. st ria Ae lE ro ng /A . st ro En M g. in in g En g. M C Annual Salary, $ Starting Salaries Jobweb.com Highest Offers by Major to 2005-06 Graduates 57,000 56,000 55,000 54,000 53,000 52,000 51,000 50,000 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