It can be very intimidating when a component on a board gets hot, exhibits unexpected behavior, does nothing at all, or even explodes. Describe the basic procedures used to test a diode in an electronic power supply. Study unit understanding and using electronic diagrams. The scope of this section is really to focus on troubleshooting the problems associated with conformal coating processing and production. An electrician is troubleshooting a faulty light circuit, where the power source. I took my first electronics repair course back in the year 1987.
It functions like the printed circuit boards used in most electronic products, or like how the walls are used for mounting the electrical wiring in your home. Suppose that something goes wrong in this voltage divider circuit, and the load voltage suddenly falls to zero. The circuit below is a typical basic transistor circuit. Why is an intermittent electronic circuit malfunction difficult to detect.
My name is jestine yong and im a professional electronics repairer and an instructor. Many identical address and data bus lines share the same electrical characteristics and make the fault finding process a challenge. How to troubleshoot electronics down to the component level. Control repair printed circuit boards adjustable speed. In 1991 i was hired by a firm to repair various electronics equipment. A virtual troubleshooting exercise such as this one is a good way to start students thinking in the right ways to becoming effective troubleshooters. This is an integrated circuit that has regulation and protection circuits built into one package. Huntron tracker poweroff circuit board test uses analog signature analysis to detect and isolate component faults on boards beyond poweron functional testing. The unexpected behavior exhibited by the circuit is due to improper locating or soldering of components, component damage due to aging, faults, overheat, and so on. Most ee components and elements used in electrical and electronics equipments, devices and instruments are common in their functions and operations. Electronic repair troubleshooting tips and secrets for. For troubleshooting, i usually start by measuring voltages around the circuit. Any study guide out there or good books on troubleshooting circuit boards with or without schematics. You will learn to implement procedures for the testing of electronic components as well as carry out simple repair procedures for the correction of faults on printed circuit boards with confidence.
See if the circuit can be divided into sections small sections or stages are far easier to troubleshoot or eliminate than entire circuits. A special type of conductor found in many electronic applications is the shielded wire or coaxial cable. Though sometimes it was quite time consuming, we still enjoy it. Troubleshooting of an electronic circuit is a process of having a special outlook on components that comes out with remedies to repair it.
The most versatile tool used for troubleshooting pcbs is a multimeter. Explain how to properly clean an electronic circuit board. Electronic repair training circuit board repair and rework. Here is a list of split airconditioner control troubleshooting guide that you can use if you need to troubleshoot your split air conditioner unit. Keysight technologies troubleshooting a printed circuit board. One of the more difficult types of electronic repair tasks is troubleshooting bus structures on complex digital microprocessor based circuit boards.
As a technician, you are sent to troubleshoot a complex piece of electronic. If you need to repair damaged circuit boards, the allinone professional kit is just what you need. This dac is an electronic circuit mounted on the pcb to perform this task. In either case, it is sometimes necessary to repair a malfunctioning circuit board or perform some other maintenance. The analog signal is further amplified by amplifier, which is also mounted on pcb.
Electrical troubleshooting 3 measuring voltage drop observe the circuit above. After 12 years in the repairing line, in 2003 i set up my own technical training center to train students who are interested in electronics repair. Good troubleshooting skills are vital to the electronics hobbyist. Resistors a twoterminal passive component that opposes the flow of current reduces the electric current and at the same time lowers the voltage levels in a circuit.
This manual is designed to help you repair and ship good, reliable pc boards that might otherwise be consigned to scrap. Circuit troubleshooting is the highest level of thinking required of many electrical and electronics professionals. When troubleshooting, make sure mains power is disconnected before proceeding to check the printed circuit board to prevent electric shock. Most designs begin with a hand drawn schematic and design plan. When i find a voltage that does not make sense at a certain point, thats a good place to continue investigating. October 14, 2015 october 15, 2015 admin 3 comments repair, troubleshooting one of the first steps in troubleshooting an electronic circuit board is to perform a visual inspection. When coating is applied on top of the contaminant, the conformal coating is unable to adhere to the oily surface and a fish eye is caused.
Most circuit problems are due to incorrect assembly, always double check that your circuit exactly matches the drawing for it. Practical troubleshooting of electronic circuits for engineers and. Split airconditioner control troubleshooting guide. Printed circuit boards pcbs are manufactured according to designer specifications. One of the most important factors in doing this, is the approach used. The simple guide to learning electronics for beginners. This threeday seminar focuses on handson troubleshooting down to the component level without a schematic. Procedures covering bow and twist repair on circuit boards. Diagnosing of defective printed circuit boards pcb. Passive devices devices or components which do not require external source to their operation. Pcbs are very simple to troubleshoot for an experienced one, as there is not much equipment you will need in order to troubleshoot your average printed circuit board repair. Nov 29, 2010 good troubleshooting skills are vital to the electronics hobbyist. Be sure that all connections are securely fastened.
Then, using software, an electronic version of the schematic is created. Tv circuit board diagram repair pdf data wiring diagram flat panel tv diagram of internal parts and circuit boards note. However, errors can occur during the construction process, or accidents happen along the way that render them faulty. Is this the only fault, being that it is the only component visibly damaged. There are several basic steps involved in producing a printed circuit board pcb. Fish eyes are normally caused by a contaminant on the surface prior to application of the conformal coating. The perfect compliment to a 2yr technician course at a junior college or vocational school. I try to find points out that should have a certain voltage, then measure it. The test leads are connected in parallel across the circuit load.
With a 12 volt power source connected to the load, the meter should read a voltage drop equal to the source voltage or 12 volts. Expected voltage readings when testing a transistor circuit with a multimeter. Yet, were driven by simple economics and must repair damaged pc boards whenever possible. This simple troubleshooting technique is applicable to a wide variety of electrical, electronic, and other types of systems. Typically, that contaminant is a substance like a silicon contaminant.
These electronic devices range from consumer electronics such as. Troubleshooting and using circuit laws gaining circuit familiarity troubleshooting basics common troubleshooting techniques the program the practical troubleshooting of electronic circuits workshop will teach you how to recognise and efficiently troubleshoot common electronic component and circuit problems. After 12 years in the repairing line, in 2003 i set up my own technical training center to train students who are. Basic troubleshooting strategies worksheet basic electricity. Animals and rodents can also be the cause of electrical or electronic. What is clear is that the first two areas, selection of material and application method, relate to the holistic approach to conformal coating discussed earlier. The workshop will give you a solid understanding in common electronic terminology and symbols, as well as the construction and operation of common electronic components. The shipping and transporting can also loosen or damage circuit boards and components. How to diagnose and fix everything electronic, second. To expertly troubleshoot electrical equipment, problems must be solved by replacing only defective equipment or components in the least amount of time. Learn how to troubleshooting repairing the lcdled tv and lcdled monitor screen some repairer will call it as. Analogue signature analysis to test the unpowered printed circuit boards pcbs.
Download our pdf guide solving conformal coating problems in the application process now. Identify and measure most of the basic electronic components so that you can start to troubleshoot any type of electronics equipment. This video present a basic procedure to troubleshoot errors in simple electronic circuits. Many circuits are similar to it, and it provides good starting point to explain some of the points to note. The best way to become proficient in troubleshooting even to tackle difficult electronic problems is decided by handson experience with the electronic circuits. A technician following the divideandconquer troubleshooting strategy begins by measuring voltage across the lower resistor. Electronic repair is a skill and once you had mastered it, no one can snatch your knowledge away. Tv circuit board diagram repair pdf circuit diagram images. What would you recommend as the next voltmeter measurement to take in troubleshooting the circuit, following the same divide in half. The circuit shows several of the points where the voltage can be measured in a circuit. The typical plant maintenance technician will rarely see enough failures to build up any proficiency in repairing circuit boards. We will begin to search for the answer in the internet, books and electronic repair magazine, forums and from our fellow repair friends.
Aug 30, 2018 for troubleshooting, i usually start by measuring voltages around the circuit. On older printed circuit boards, the techniques used for troubleshooting were performed in a variety of ways, including the following. By comparing tracker signatures from a working circuit board to the signatures of a nonworking board, you can troubleshoot down to the component level. Be sure that parts with positive or negative markings are positioned as shown in the drawings. What instruments should be used to inspect an electronic circuit for problems. On circuit boards of the 1980s and 90s, it was possible to perform repairs with the use of automatic testing tools, which simply do not work on todays pcbs. Because most failures occur within the power sections instead of the circuit boards, they arent very difficult to troubleshoot. Feb 18, 2009 hi guys, i have a associate degree in electronics but need help on learning how to troubleshoot circuit boards using schematics. The general troubleshooting process is explained followed by a brief study of various hand tools and electronic test and measuring instruments. Pc boards have fine pitch components, ball grid arrays and fine line circuits making them a challenge to repair. With these, the circuit is prototyped and tested to verify that the design works correctly. Fortunately, electrical circuit troubleshooting is an activity that works well for small groups of students to engage in as well as individual students.
The printed circuit board assembly pcba can be found in almost any electronic devices. These circuits are easy to use, and are found in many applications. Hi guys, i have a associate degree in electronics but need help on learning how to troubleshoot circuit boards using schematics. Circuit boards are more complicated to repair today than even a few years ago. Cables generally consist of two or more conductors, usually in the same insulation jacket. How to diagnose and fix everything electronic, second edition, offers expert insights, case studies, and step by step instruction from a lifelong electronics guru. Have you ever had a printed circuit board go bad on you and you needed to repair it but you dont have schematics. Basic circuit troubleshooting worksheet basic electricity. Before getting into details of printed circuit board, there are some basics you need to know about circuits. Basically a no bs approach to troubleshooting electronics the way its done in the real world. Firstaid kits for circuit boards, timetested and guaranteed. Remove and solder electronic components from and onto pcb board. More often than not, a circuit is not going to work perfectly on the first try, especially as a beginner.
Some basic electronic repair troubleshooting tips duration. A fully revised guide to electronics troubleshooting and repair repair all kinds of electrical products, from modern digital gadgets to analog antiques, with help from this updated book. The practical troubleshooting of electronic circuits workshop will teach you how to recognise and efficiently troubleshoot common electronic component and circuit problems. Huntron trackers circuit board test and troubleshooting. Circuit board problems resource for troubleshooting. This voltage can be thought of as electrical pressure, pushing.
Recognise and efficiently troubleshoot common electronic component and circuit problems. How to troubleshoot like an expert a systematic approach. We all know the rule and importance of troubleshooting in electrical and electronics engineering. Understanding and using electronic diagrams 5 in this simple power supply, all the voltage regulation functions are done by u 1, which is a 7812 positive voltage regulator. Upon opening the cabinet door for this equipment, your nose is greeted by the pungent odor of burnt circuit board a smell you are unlikely to forget, once having experienced it. Troubleshooting is the process that determines the cause of the problem in the electronic circuit by examining the affected area of it, and then by taking appropriate action.
Transistor stages may often be tested by simply grounding base to emitter to see if the transistor turns off as expected and provide a logical 1 output or short collector to emitter to provide. The repair specialists at circuit technology center, inc. This technique includes interconnections between points printed in metal on the nonconductive board. We have multiple custom design boards that we used to help teach our students to understand electronics and how to troubleshoot electronics. Jul 03, 2014 this video present a basic procedure to troubleshoot errors in simple electronic circuits. M y name is jestine yong and im a professional electronics repairer and an instructor. Use an analogdigital multimeter to measure voltage, current and resistance for troubleshooting purposes.
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