Hi Bob, Greetings from Borneo, your videos inspired me to learn more about electronics. I'm a beginner, was laid off by my employer post-covid years. Now I have more time to learn & practice repairing the electronic board sold by my ex employer to the customers. Fortunately some of the customers still contacted me for help to troubleshoot their machine. At least I can charge them if I manage to fix their machine's power supply to make ends meet. Thanks a lot for your free educational videos 🙏👍👍👍
+Glenn Gacayan I was a tech in the 80s and 90s. These days you simply replace the board/module in many cases. Never tried to solder anything on the boards they make these days, I am not a watchmaker.
Excellent video Review!!! I was desperately looking for this info, about how to test check measure Capacitors. At most of my jobs, I just did voltage, continuity and resistance tests checks. But sometimes used to come across capacitor troubleshooting which I had forgotten. Many other "you tubes capacitor videos" talk so much never explain plainly, go to the point, never really explain show so clearly the good capacitor points You made. E.g. specially the one, about BEFORE working testing them YOU HAVE TO DISCHARGE them. You made an awesome video. This video was good similar to the way it was explained taught to us many years ago in College. I was trying to remember had forgotten a lot about capacitors. Awesome review, points explanations you made. Thanks!
Oh, another GOOD Point You made and many others "capacitor videos" fail to explain make a point of, or even mention it, that before measuring test them; you have to Removed the capacitor from the circuit. Makes a lot of sense (get wrong different multimeter readings). Thanks Mr. Bob!!! Thumbs-up to you Sr.!
Hi! In my life, I had to design, to teach, and I was a process engineer in one of world's top SMS capacitors Industries in USA's land. There is a lot to teach. I just mention the basics about capacitors. TH-cam has top guys with great knowledge and teaching videos. But sadly there are also pay by click hunters, laking of knowledge who became famous trying to make videos from the minimum knowledge. It is hard for the knowledge searches to find videos between entertainers and teachers, without to watch one by one until they find what they looked for. Maybe someday TH-cam will create a database, able to classify videos by resume, info, and more specific categories as entertainment or educational in the spoken subject. Thanks Robert by writing. :-)
Great video and explanations; thank you so much! I'm in the learning stage and your video helped me a lot. I'm new, but I'm learning.... Thank you again Bob.
I've got a 250v 150uF Capacitor 105 Celsius which I pulled out of tv main board, checking all the components. It's reading 136 uf on my meter. What do think, number on cap too low to re-use? Or still in range?
if i have a small smd capacitor like in the end of you video. can you measure continuity between the legs on it to if its short or do i have to remove it first ? why need to remove it, maybe removing only needed when want to read capacitance
watching your video from Kenya, Eastern Africa..best well explained and clearer video and educative one. Thanks for that i really needed it BOB. THANK YOU. looking forward to watch a video on --how to test a complete circuit of a Whoofer.
Kenya! Wow! After a cold winter I wish to go there. I had to heat my little electronics lab for hour and a half before to start to work. I will make more videos soon. I was waiting for the temperature to increase. If you see my clothing, in some of my videos, I am wearing 5 t-shirts to record a video. lol Thank you Daiv! :-)
Hi! I don't know. When I moved to a new country, my mother in law made a deal with some people who gets broken electronics to use plastics to "heat their house in winter". She asked them to bring the PCBA and she pays some money that helped them a lot. I started here with a repairs with a full inventory of spare parts from it. After one year, I retired from repairs and I got to next level as electronics engineer in manufacturing and design. Now I use those PCBA for teachings. But I have not idea from which device or brand are the PCBA from. (This one looks like a TV's power supply. The small one is an Epson Printer's power supply).
In your clip, around 7:00, you're stating that the band on the capacitor correspond to the outer foil connection. In fact, this should be considered as an ideal situation. I found capacitors that were not marked properly in that regard, having the band on the lead which was connected to the inner side. This discovery is based on a youtube video where the technician was connecting a capacitor on a CRO and based on the noise amplitude introduced while holding the capacitor between fingers. If the amplitude is at its lowest when the band side is connected to the scope's negative lead, then the band on the capacitor is pointing to the outside foil lead, otherwise the band is pointing to the inner one. I've been successful to perform that test only with a CRO. While doing it using a DSO, the results weren't as convincing.
+SimpleEnough2k9 Hi! There is not discovering in TH-cam for anybody. Video: 15:22 The knowledge comes from several decades ago before my father borne! Since the beginning of any electric component, there are a lot of test, investigation, datasheets, and updates to product introduction to main universities and manufactures handbook. All brand cares very well about an electrolytic capacitor's mark. But most brands don't care anymore about the non polar foiled capacitors. And the mark can be on any side or missing that all now day's. In minute 7:15 I sad: " ...many years ago, Fabricants USED to mark where is the outside paper for designers to know"... When we say they used to, it means in English: that it is not use anymore. Evidence of it, is most capacitors alike you will see now days, are missing the mark. I talked about because this knowledge will not escape from the list of cares of any designing engineer. But some "fast food" technical schools let the students to graduate missing that knowledge. Or in the worse situation, people are trying to learn only from TH-cam, and forget to go to school, or to search in books as the main source of formal education. The one that could be confuse about in my video is I didn't talk about Tantalum capacitor. I spoke, but jumped it, leaving it out the subject for next video.
what do you set your multimeter at to test the photo cell in my motion sensor light. the light works but the light will come on even in the daylight, so i want to test the board and i think its a cds, marked on the board?
Hi! For a simple photo cell test use Ohms meter. For function test, use voltage meter. The best way to get a good result is to set up a "window comparator circuit". It can be done with 2 Operational Amplifiers. I recommend to use the ones that works OK with +V and Gnd, and voltage between 3 and 5 Volts if it is the case. Set the voltage level upper of 160mVolts. (The better is something close to half Vcc). There are low noise comparators too. If you work with photocells or phototransistors, you must make the window comparator in order to control the light's hysteresis or to reduce the noise's effects.
ON MY POWER SUPPLY UNDER IT IT HAS NON CONDUCTIVE PAPER THAT HAS PLASTIC RIVET HOLDING IT UNDER THE CIRCUIT BOARD IS THERE ANY SPECIAL WAY TO REMOVE THE PLASTIC RIVETS OR HAVE SEEN THEM THANK YOU
+wolfenstein1040 Good question! We use 5 Watts, 10 or 25 Watts resistors. Any value in Ohms between 100 to 4.7K can be OK. (In reality any good resistor from the ones you have on hand). There is a capacitor discharge formula = [5 x (R x C)]. R is the resistor in Ohms, C is the capacitor in Faraday, and multiplied 5 times. BUT, that "5" is a constant number used for a good connection discharge. So, for safety, YOU MUST last about 3 times the value of the formula, once you made a good contact between them. ;-) (Try to find high Ohms resistors for the main high Voltage capacitors discharge. The lower of the resistor, the higher of the Watts for it)!
Hi! Try to get the datasheet for it. In case of there was not data, then you will have to measure it or set up a circuit with a chip 555 to calculate the capacitance value.
Thanks Bob, I'm trying to learn how to fix electronics but as you stated... I'm trying to learn what I think I need to know from TH-cam. What books would you recommend and do you have a supplier for capacitors used in modern LED TV's and motherboards? Since i was a kid I would take my electronics apart and I've seen more than what you showed but not sure what function each type of capacitor is used for?
Yes. The capacitor has been charged to its normal voltages, and all the reverse voltage protection is done in diodes, transistors and ICs. The problem will be if we charged the capacitor outside of the circuit, and later try to insert it charged, because maybe we charged the capacitor with more voltage than its normal operation voltage.
Thanks ! Im trying to fix a 36 v battery charger . I saw a video on fixing a battery charger that keeps blowing fuses . He was saying that is is usually the rectifier that is the problem . I switched my volts meter to 115 and it was meant to be on 220v and I pluged it into the 220v wall socket and not the charger keeps blowing fuses . I dont know a heck of allot about circuit boards .
So I had a look at the board and the only think I can think of is that the first track that leads to one of the biggest compositors on the board my be the one that is faulty . Its really hard to tell cause it does not seem to be damaged and i cant see anything else that seems out of place .?
Hi, thank you so much for your video! Please I need your help! Hi, I'll appreciate if you give me this advice, by chance do you know if the old capacitor 250V PME 271M 0.1 μf X2 40/85/56 it needs to be discharged in the circuit board before remove it or the new one that I got PME 271 M 0.1 μf X2 40/110/56/B how? if so how I can discharge it? With resistance or simple metal? Thank you for your help.
Hi! I spoke about it in in this video: th-cam.com/video/5tX-szcPaD0/w-d-xo.html The best idea is discharge it in 1 or 2 seconds. T=1/(5*t,) ...and t=C*R. Remember I = V/R and Power in the resistor = V * I. Use insulation! Thanks by asking. :-)
Hi i have the same type of tester u hv but wen i test a cap say 100uf...i get a reading of 80 uf...but wen i test it with my fluke tester it show 99uf...is something wrong with my tester? How do i zero my meter cos i hv a manual but is in chinese...pls advice if i should zero in every range reading to test.?
Hi! Large capacitors requires more time to be measured. But also, this kind of testers can be damaged easily with a charged or partially charged capacitor. DMM are made to measure high voltages and 10 or 20 Amperes, what makes them little more restan to damages. No all the time, but some times, a capacitor discharge damage affects only one or few scales but no all of them. To zero the capacitance meter is a need for low scales. But high scales does not need to zero adjust.
Hola Bob. Muchas gracias por compartir tus conocimientos. Quiero preguntarte si ese medidor de capacitancia sirve también para toda clase de telefonos moviles como iphone y samsung.
Hi! You have to do two tests. - One is continuity to ground: negative lead on ground, and touch both sides of the capacitor with the positive lead of the tester. In some capacitors, there will be continuity to ground in one side, but no the other side. - The other is continuity, and better with Ohms meter, in both sides of the capacitor. There should not be short circuit or low resistances. For anything suspicious, remove one side of the smd capacitor for capacitance meter test. A lot of the capacitors are 0.1 uF in parallel with everything just to bypass noise. Those ones, get shorted in laptops, tablets, and smartphones, making a whole area in short. You can remove it, and everything will work. It happens a lot, because the Voltage rate is low on them, and become sensitive with the time and easy to short circuit. :-)
For the first test: continuity with a "beep" sound to work faster. For the 2nd test: Ohms meter. If one of them looked suspicious, remove the solder in one side or the component that all and measure it with the "CAP" or "-I I-" symbol in the DMM dial if it is available in your DMM, or with a capacitor meter. DO NOT FORGET to always discharge the capacitor with a short circuit before to perform a measurement. ;-)
Hi there , it was great tutorial video . please make a tutorial video about how to read schematic laptop motherboard for beginners, what's means the symbol and how to find voltage for which component and diagnose for repair laptop . thnx
Bob kalpon my name is Saleem , I really thank you very much for your effort in making this video I really appreciate everything you have taught me today you are a very nice guy especially at the end when you said dont rely on youtube but look at the books ....so I wanna go to school for that but dont know what to ask for to learn about capacitors and mother board repair like ellectronics repair so please help me go study for it what should i look for? Thank you.
hola Mi amigo.. gracias por el video..tengo una pregunta que no tiene nada que ver con el video. yo tengo ese capacitor meter igualito a ese , y accidentalmente le meti 120 volts ac, por tener a un lado mi medidor de voltaje,, me equivoque de terminales, y nomas escuche un tronidito,,entonces ahora nomas prende el display, y se queda en ceros,, pero no mide,, lo abri y adentro tiene un fusible y lo probe y esta bueno,, entonces estoy buscando el daño.. tiene usted una idea de que componente pudo haberse dañado?... gracias
Yo no he abierto el mío. Pero por casulidad, recuerda que algunos componentes pueden estar en corto circuito en la entrada de la medicion. Sin batería, busca si hay corto en los terminales.
Best regards to my viewer friends from Philippines! (I also have a friend from Philippines at Jacksonville FL, who I consider almost a brother, and I miss other friend who was a great politician from Philippines who already passed away and rest. My blessings to all of you. :-)
Very informative though I would appreciate if if it will include also interpreting the results of the test/s say, that polarized electrolytic capacitor for charging but not discharging properly or, that it's discharge is somewhat "clipped" or, that it shows a high leakage current - all indicative of a bad capacitor and (please, as would in some forums) that one does not need for that capacitor to bulge in it's head or even explode. Since you have also indicated smd capacitors (which may include those polarized tantalum capacitors), does the testing and the test results of that polarized electrolytic capacitor apply the same to that of a polarized smd tantalum capacitor or does the latter behave differently from the former? I have right now 3 brands of smd tantalum capacitors of which 2 are from AVX and NEC/TOKIN. The 1st brand behaved as expected when tested just like that of the electrolytic capacitor in say, bias-reverse-bias (charge/discharge state.). The other two, AVX and NEC/TOKIN, did not.
Sir at the end you mentioned that go to read books and dont got TH-cam but sir in Books their is no chapter or topics include where we can read how to test components. Sir if you have any book testing equipment or devices than kindly sir share it with me I will bought soon
+abid saleem Hi! Most electronics engineering books, are written by engineers, and master in electronics who know what they are doing. Sadly for the "confusion", anybody with a free Gmail account, can upload a video with wrong information, and it is watched for millions who will learn something wrong. My best advice, because most of you are out of English speaking countries, and some of you doesn't have formal education in electronics; I recommend to go to a main city, visit a good book store, and look for "fat" electronics engineering books, with samples and mathematical formulas. Those books are expensive. But a good advise is do not buy them in the first trip. Take information about the book title, writer, edition, and check in google if you can download it "free" in pfd format or to find it to read free in books on line. :-) (Sadly, there is always a big separation between electronics engineering and technical repairing. One only teaches to calculate the right capacitor. But only the other teaches how to test them and remove it). I will try to make a video about books in the future. And I will ad more videos about testing too.Thank for the question.
Aha! I had the same problem in the middle of the 80's. That happens because the humanity history is just starting to be written, and the technology chapters are in the process. Dear colleague, next generation depends of us to get those books. It is the reason why I started to make videos. I used to teach engineering from books to 15 students in the classroom. Nowadays, I got about 80.000 "viewers" in TH-cam, and maybe some students from it, and I am teaching technical skills for repairing. I hope to add 3 more books to the market with some of the knowledge to apply in the workshop. (I think the problem is because in most countries there is a Superior Education Organization who supervises very well upon Universities. But they totally ignores the technical academies and informal training schools).
Very true sir... you really touch the grib of the students....I really like your all videos and specially ur response in quick time.......GOD give u better health its my wish and pray
hola, tendrás este video en español, busque en tu canal y no lo encontré, me gustan mucho tus videos son geniales y ayudan mucho a personas como yo que les gusta la electrónica como hobby.
+ckreitlein Thank you! The main idea was to show to test SMD caps and teach some tricks like the right polarization for non polar caps for new designers. Another video is on the way.
Hi Bob,thanks to share your experience with all of us, i´m a total beginner in electronics field but I would like to learn more because I like challenges like finding the defect and repair it, naturally i´m not an engineer or a technician but like every other human being I have an Intelligence :) Ok after this long introducing I would like to ask you about measurement with a multimeter of capacitors, I have bought a multimeter with capacitance function with an up limit of 200uF , my question is if I can measure capacitance of capacitors over 200uF or not, I have some polymer aluminium electrolitic capacitors with capacitance of 270uF and 470uF and the multimeter doesn´t read them, is that normal or I making a mistake???? Another question as newbie that I want to make , is possible to measure the capacitance of a capacitor without desoldering it from the PCB???? I ask because desoldering is so boring but in TH-cam I have seem some videos of users they say it´s possible and other instead that say is not possible to because you will not have the right value of capacitance, sorry for the long message..........I have my subscription to your channel and I wish you all the best for it. Thanks Luca
I had the same exactitude in the mid 80's. There was not any electronics school in my town, but I wanted to learn, and learn it all and to grow and to be on of the best... In 1989 I registered my first patent, and 10 years later against all the adversity I graduated as engineer. Now day's, 600.000 people watched my videos and I am able to help people like me, searching for knowledge in electronics. Don't stop, be humble and always ready to learn. I wish you the best, and welcome to the wonderful electronics world. "This is electronics. We don't work. ...we just enjoy with it". ;-)
Thanks I am just learning I'm retired and hate it so I was wanting a hobby but now I want to learn electronics and go back to work for a few more years. thanks for helping me understand resistors. 1 question Bob How do you know the Resistor is bad? Does it have to be within that range or what if its 6% over?Do I consider it bad?
Well done! You are just retiring from your job. But, life goes on, and it is just a new begining again in life. Don't stop. "This is electronics. We don´t work. We just enjoy it". :-)
If you hold the discharge resistor wire with the metal pliers (you were not holding the insulated part) and if it is 200v and charged, you could give yourself a hell of a zap...
Yes, after 30V we must use insulation. Also the discharge time should be the capacitance times the resistor times 5. Any capacitor after 35V indication must be handled carefully.
Hello Bob! Is there a capacitor that be used as a fuse?There was a aluminium housing fuse with 5A 32V tolerance and blew away like an Elko but no where to find something like that.Is is allowed to replace it with the ordinary fuse?
Hi! It has to be a multimeter with capacitance meter function. Then it will be as simple as to use a single capacitance meter. If your multimeter doesn't have the function, then there are more step method as applying ac voltage with a serial resistor to a non polarized capacitor, and calculate Xc. If the capacitor is polarized, then connect two capacitors in serial (-+,+-) with the centers pointing inside, plus a serial resistor to the AC source to calculate Xc. You will have to look for the Xc formula, but the experiment will help to learn a lot. (Be careful, because capacitors calculations must always be done with Peak or Peak to Peak Voltage). For your experiment you will look for AC RMS to Peak to Peak Voltage convention, RC serial calculation, RC impedance, and Xc capacitive reactance calculations from most good basic electronics or electric principles books.
So I did, and learned nothing except how to lift one end of a capacitor (which I already knew). The sound is so bad anyway I didn't know what point the chap was making.
Hi Mr Bob.Very instructive but you have not tested any capacitor after you have lifted one side of them + it would have been very interesting to show the difference between "open" and "short" at the same time
Very useful video but the way you remove smd capacitors from the pcb is not properly correct. In the second case it is quite clear you are lifting one of the land from the laminate surface. Ciao!
Hi! For SMD capacitors we can use hot air to remove it, soldering iron with special tip and connected to a soldering station for proper one side lift up, or soldering iron with tweezers connected to a station for removing the biggest SMD. Some people like more to remove them with hot air. I was a process engineer in an American SMD capacitors industry, and I know no one rework process is too healthy for them, and in that case I rather to lift up one side. I respect your opinion, but no as a teacher, but as a process engineer who made the SMD capacitor from A to Z, and certified for quality in a ISO manufacturing, I avoid all the over heating in repairing procedures.
Unfortunately the lighting and camera close up is not efficient or clear. Sorry for the comment or criticism but it's TRUE. Get the appropriate equipment for soldering removing and installing surface mount capacitors.
in some other dialect besides English maybe, don't folks review there work before posting them? I suppose no one hears their own accent but someone should be giving editorial review input prior to posting.
Thanks Ahmed. Teaching is always a hard task to do. Teaching electronics involves more than pedagogic knowledge or an engineering profession. It is more through the years of experience, where we learn more about student's needs. Education is a stair process. Students learn more and faster as we add more steps and deepest bases. It is the right way to bring a student from zero to the highest level of knowledge. I learned to listen to people and to teach in function of their needs. I am not the best teacher or engineer because I have to enforce to make it for four European languages, for different knowledge levels or professions. In this Channel, I teach only very basic electronics in two languages. Try to be a good student to learn always more. And remember, the only way to measure success is by results. More than half Million people watched my videos and gave already a good feedback to stay on in this TH-cam Channel. This Channel is for people like you an me, from all the world, who search knowledge to be better and to be success. Thanks for writing, and sharing your opinion. Stay close! I there is a group of colleagues, students and friends who are always in touch, and I never forget about them in this Channel.
+Joseph Gosselin (Popple) Hi! I spoke about how to treat electronics after water in my video: th-cam.com/video/ePXSxXqLTA0/w-d-xo.html (Use high degree alcohol, a soft brush, and pressure air to rinse it. Other ways, in a few weeks it could become as the laptop in my video: th-cam.com/video/-Gh_LXvhap4/w-d-xo.html
Hi Bob,
Greetings from Borneo, your videos inspired me to learn more about electronics. I'm a beginner, was laid off by my employer post-covid years. Now I have more time to learn & practice repairing the electronic board sold by my ex employer to the customers. Fortunately some of the customers still contacted me for help to troubleshoot their machine. At least I can charge them if I manage to fix their machine's power supply to make ends meet.
Thanks a lot for your free educational videos 🙏👍👍👍
i have been viewing many of theses to test my blown lg flatiron. this is the most thorough of the dozens of videos. thanks bob!
+G Borden Thank you. I am on the way to make another video about an extra test outboard.
G Borden hi
@@bob.kalpon1398 well i think u should go and study ..u and your disgusting video ....u cant test all kinds of caps with your multimeter..
Good
this info has really helped me. I love those words of encouragements at the end of the video.
thanks bob!! im an electronic technician my self, as my professor said before, "electronics technician must never stop studying"
100% Right! :-)
+Glenn Gacayan I was a tech in the 80s and 90s. These days you simply replace the board/module in many cases. Never tried to solder anything on the boards they make these days, I am not a watchmaker.
What is the defference between black color capacitor and blue color capacitor but same resistance 100uf 16v is this same or have difference??
I missed the part where you actually told us how to test the capacitor
he got lost somewhere, somebody need to bring him back to the path
8:27
@@l3ertuz362 Noe knows about finding the path
Steve Jeffryes thank you for not allowing me to waste my time.....
@@wonder-bred cheers g
do you think ESR testers are accurate for testing caps on the boards ?
Congratulations! A very useful and practical lesson for us who take the theory to the bench.
Excellent video Review!!!
I was desperately looking for this info, about how to test check measure Capacitors. At most of my jobs, I just did voltage, continuity and resistance tests checks. But sometimes used to come across capacitor troubleshooting which I had forgotten. Many other "you tubes capacitor videos" talk so much never explain plainly, go to the point, never really explain show so clearly the good capacitor points You made. E.g. specially the one, about BEFORE working testing them YOU HAVE TO DISCHARGE them.
You made an awesome video. This video was good similar to the way it was explained taught to us many years ago in College. I was trying to remember had forgotten a lot about capacitors. Awesome review, points explanations you made. Thanks!
Oh, another GOOD Point You made and many others "capacitor videos" fail to explain make a point of, or even mention it, that before measuring test them; you have to Removed the capacitor from the circuit. Makes a lot of sense (get wrong different multimeter readings).
Thanks Mr. Bob!!! Thumbs-up to you Sr.!
Hi! In my life, I had to design, to teach, and I was a process engineer in one of world's top SMS capacitors Industries in USA's land. There is a lot to teach. I just mention the basics about capacitors. TH-cam has top guys with great knowledge and teaching videos. But sadly there are also pay by click hunters, laking of knowledge who became famous trying to make videos from the minimum knowledge. It is hard for the knowledge searches to find videos between entertainers and teachers, without to watch one by one until they find what they looked for. Maybe someday TH-cam will create a database, able to classify videos by resume, info, and more specific categories as entertainment or educational in the spoken subject. Thanks Robert by writing. :-)
Thank you for this clear and wonderful tutorial👍 and of course the encouragement to study ❤ you got my full support
"Thank You", thank you very much. Your presentation was REALLY good 😎
Great video and explanations; thank you so much! I'm in the learning stage and your video helped me a lot. I'm new, but I'm learning.... Thank you again Bob.
And when testing a capacitor on board like on @13:33 and both sides don't do any sound, what to do?
I've got a 250v 150uF Capacitor 105 Celsius which I pulled out of tv main board, checking all the components. It's reading 136 uf on my meter. What do think, number on cap too low to re-use? Or still in range?
if i have a small smd capacitor like in the end of you video. can you measure continuity between the legs on it to if its short or do i have to remove it first ? why need to remove it, maybe removing only needed when want to read capacitance
New subscriber here sir.. i am a beginner and it helps me a lot getting an idea about how to test capacitors. I learned so much.. thank you sir
watching your video from Kenya, Eastern Africa..best well explained and clearer video and educative one. Thanks for that i really needed it BOB.
THANK YOU.
looking forward to watch a video on --how to test a complete circuit of a Whoofer.
Kenya! Wow! After a cold winter I wish to go there. I had to heat my little electronics lab for hour and a half before to start to work. I will make more videos soon. I was waiting for the temperature to increase. If you see my clothing, in some of my videos, I am wearing 5 t-shirts to record a video. lol
Thank you Daiv! :-)
Very well explained Bob, thanks from Macedonia!
4:55 wouldn't holding the pliers by the metal piece shock you?
...Keep the videos coming! This one was great! I'd like to know more about testing with a Multimeter and other testing equipment
Very instructive video, look forward to the watching others.
:-! :-! L
Mh6
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Wow, why is that power supply at 9:13 so huge? What device does it power?
Hi! I don't know. When I moved to a new country, my mother in law made a deal with some people who gets broken electronics to use plastics to "heat their house in winter". She asked them to bring the PCBA and she pays some money that helped them a lot. I started here with a repairs with a full inventory of spare parts from it. After one year, I retired from repairs and I got to next level as electronics engineer in manufacturing and design. Now I use those PCBA for teachings. But I have not idea from which device or brand are the PCBA from. (This one looks like a TV's power supply. The small one is an Epson Printer's power supply).
In your clip, around 7:00, you're stating that the band on the capacitor correspond to the outer foil connection. In fact, this should be considered as an ideal situation. I found capacitors that were not marked properly in that regard, having the band on the lead which was connected to the inner side. This discovery is based on a youtube video where the technician was connecting a capacitor on a CRO and based on the noise amplitude introduced while holding the capacitor between fingers. If the amplitude is at its lowest when the band side is connected to the scope's negative lead, then the band on the capacitor is pointing to the outside foil lead, otherwise the band is pointing to the inner one. I've been successful to perform that test only with a CRO. While doing it using a DSO, the results weren't as convincing.
+SimpleEnough2k9 Hi! There is not discovering in TH-cam for anybody. Video: 15:22 The knowledge comes from several decades ago before my father borne! Since the beginning of any electric component, there are a lot of test, investigation, datasheets, and updates to product introduction to main universities and manufactures handbook.
All brand cares very well about an electrolytic capacitor's mark. But most brands don't care anymore about the non polar foiled capacitors. And the mark can be on any side or missing that all now day's.
In minute 7:15 I sad: " ...many years ago, Fabricants USED to mark where is the outside paper for designers to know"... When we say they used to, it means in English: that it is not use anymore. Evidence of it, is most capacitors alike you will see now days, are missing the mark.
I talked about because this knowledge will not escape from the list of cares of any designing engineer. But some "fast food" technical schools let the students to graduate missing that knowledge. Or in the worse situation, people are trying to learn only from TH-cam, and forget to go to school, or to search in books as the main source of formal education.
The one that could be confuse about in my video is I didn't talk about Tantalum capacitor. I spoke, but jumped it, leaving it out the subject for next video.
what do you set your multimeter at to test the photo cell in my motion sensor light. the light works but the light will come on even in the daylight, so i want to test the board and i think its a cds, marked on the board?
Hi! For a simple photo cell test use Ohms meter. For function test, use voltage meter. The best way to get a good result is to set up a "window comparator circuit". It can be done with 2 Operational Amplifiers. I recommend to use the ones that works OK with +V and Gnd, and voltage between 3 and 5 Volts if it is the case. Set the voltage level upper of 160mVolts. (The better is something close to half Vcc). There are low noise comparators too.
If you work with photocells or phototransistors, you must make the window comparator in order to control the light's hysteresis or to reduce the noise's effects.
can I test and measure without unsolder from the board or are number always wrong like that....?!
ON MY POWER SUPPLY UNDER IT IT HAS NON CONDUCTIVE PAPER THAT HAS PLASTIC RIVET HOLDING IT UNDER THE CIRCUIT BOARD IS THERE ANY SPECIAL WAY TO REMOVE THE PLASTIC RIVETS OR HAVE SEEN THEM THANK YOU
4:59 - firstly, how long would it take to discharge and secondly, how will you know that it is discharged?
It can vary obviously but you can connect a volt-meter and see the values drop as it discharges.
Good job - very professional and quite detailed
Most exellent demo sir.well done.keep up the great work.
+Bob. Kalpon sir, how much time or physical sense, do I need to wait to discharge a large capacitor like the example you showed in your video?
+wolfenstein1040 Good question! We use 5 Watts, 10 or 25 Watts resistors. Any value in Ohms between 100 to 4.7K can be OK. (In reality any good resistor from the ones you have on hand). There is a capacitor discharge formula = [5 x (R x C)].
R is the resistor in Ohms, C is the capacitor in Faraday, and multiplied 5 times. BUT, that "5" is a constant number used for a good connection discharge. So, for safety, YOU MUST last about 3 times the value of the formula, once you made a good contact between them. ;-)
(Try to find high Ohms resistors for the main high Voltage capacitors discharge. The lower of the resistor, the higher of the Watts for it)!
"and some have the shape of pillows" 😂😂 love it
..
I loved it when he said that IT COULDNT be explained any better 😁😁😁😁
Hello nice video almost helpd me if on a capacitor is (M 3a 471 OJ) how can I find out please help
Can you use a light bulb to discharge the capacitor so that you can easily tell when it's finish?
Hello, I recently pulled out a capacitor from a disposable camera, what do you think would be the average size for one of those??
The only numbers on it look like this:
8(2)
5w
Hi! Try to get the datasheet for it. In case of there was not data, then you will have to measure it or set up a circuit with a chip 555 to calculate the capacitance value.
Thanks Bob, I'm trying to learn how to fix electronics but as you stated... I'm trying to learn what I think I need to know from TH-cam. What books would you recommend and do you have a supplier for capacitors used in modern LED TV's and motherboards? Since i was a kid I would take my electronics apart and I've seen more than what you showed but not sure what function each type of capacitor is used for?
Hi! Where are you? ...and what is your native language? (Let's see how can I help you) :-)
is it safe for the circuit board to discharge a compositor while it is still on the circuit board ?
Yes. The capacitor has been charged to its normal voltages, and all the reverse voltage protection is done in diodes, transistors and ICs. The problem will be if we charged the capacitor outside of the circuit, and later try to insert it charged, because maybe we charged the capacitor with more voltage than its normal operation voltage.
Thanks !
Im trying to fix a 36 v battery charger .
I saw a video on fixing a battery charger that keeps blowing fuses .
He was saying that is is usually the rectifier that is the problem .
I switched my volts meter to 115 and it was meant to be on 220v and I pluged it into the 220v wall socket and not the charger keeps blowing fuses .
I dont know a heck of allot about circuit boards .
So I had a look at the board and the only think I can think of is that the first track that leads to one of the biggest compositors on the board my be the one that is faulty .
Its really hard to tell cause it does not seem to be damaged and i cant see anything else that seems out of place .?
Hi, thank you so much for your video!
Please I need your help!
Hi, I'll appreciate if you give me this advice, by chance do you know if the old capacitor 250V PME 271M 0.1 μf X2 40/85/56 it needs to be discharged in the circuit board before remove it or the new one that I got PME 271 M 0.1 μf X2 40/110/56/B how? if so how I can discharge it? With resistance or simple metal?
Thank you for your help.
Hi please I wish to ask I can use any resistor to discharge a capacitor of 200v and above?
Hi! I spoke about it in in this video:
th-cam.com/video/5tX-szcPaD0/w-d-xo.html
The best idea is discharge it in 1 or 2 seconds. T=1/(5*t,)
...and t=C*R.
Remember I = V/R and Power in the resistor = V * I.
Use insulation! Thanks by asking. :-)
Hi i have the same type of tester u hv but wen i test a cap say 100uf...i get a reading of 80 uf...but wen i test it with my fluke tester it show 99uf...is something wrong with my tester? How do i zero my meter cos i hv a manual but is in chinese...pls advice if i should zero in every range reading to test.?
Hi! Large capacitors requires more time to be measured. But also, this kind of testers can be damaged easily with a charged or partially charged capacitor. DMM are made to measure high voltages and 10 or 20 Amperes, what makes them little more restan to damages. No all the time, but some times, a capacitor discharge damage affects only one or few scales but no all of them. To zero the capacitance meter is a need for low scales. But high scales does not need to zero adjust.
out standing i just learn how to do this now thank you
You look like Muhammad Ali ! I am a beginner and love your videos I lie in Florida Thank You
Hola Bob. Muchas gracias por compartir tus conocimientos. Quiero preguntarte si ese medidor de capacitancia sirve también para toda clase de telefonos moviles como iphone y samsung.
yes but why in some cases i find contact " BIIP "on fisrt and second point of capacitor if it is mounted and it's ok if i dismount from MBO ?
With all the rest Thanks for the video well explian and good video recording many will learn from this videos do the next we are waiting BOB
Thanks!
Joseph Cauchi
Great video! keep up the work, nice work!
Joseph Cauchi
Naren Soutavong j
Mr. Bob Kalpon, Where should I put the tester to identify the short circuit? Thanks!
Hi! You have to do two tests.
- One is continuity to ground: negative lead on ground, and touch both sides of the capacitor with the positive lead of the tester. In some capacitors, there will be continuity to ground in one side, but no the other side.
- The other is continuity, and better with Ohms meter, in both sides of the capacitor. There should not be short circuit or low resistances.
For anything suspicious, remove one side of the smd capacitor for capacitance meter test. A lot of the capacitors are 0.1 uF in parallel with everything just to bypass noise. Those ones, get shorted in laptops, tablets, and smartphones, making a whole area in short. You can remove it, and everything will work. It happens a lot, because the Voltage rate is low on them, and become sensitive with the time and easy to short circuit. :-)
Thank you, just I need to know how to set up the digital multimeter, I do have the shipest version. Is it in DCV? Thank you
For the first test: continuity with a "beep" sound to work faster. For the 2nd test: Ohms meter. If one of them looked suspicious, remove the solder in one side or the component that all and measure it with the "CAP" or "-I I-" symbol in the DMM dial if it is available in your DMM, or with a capacitor meter. DO NOT FORGET to always discharge the capacitor with a short circuit before to perform a measurement. ;-)
Hi there , it was great tutorial video . please make a tutorial video about how to read schematic laptop motherboard for beginners, what's means the symbol and how to find voltage for which component and diagnose for repair laptop . thnx
Bob kalpon my name is Saleem , I really thank you very much for your effort in making this video I really appreciate everything you have taught me today you are a very nice guy especially at the end when you said dont rely on youtube but look at the books ....so I wanna go to school for that but dont know what to ask for to learn about capacitors and mother board repair like ellectronics repair so please help me go study for it what should i look for? Thank you.
hola Mi amigo.. gracias por el video..tengo una pregunta que no tiene nada que ver con el video. yo tengo ese capacitor meter igualito a ese , y accidentalmente le meti 120 volts ac, por tener a un lado mi medidor de voltaje,, me equivoque de terminales, y nomas escuche un tronidito,,entonces ahora nomas prende el display, y se queda en ceros,, pero no mide,, lo abri y adentro tiene un fusible y lo probe y esta bueno,, entonces estoy buscando el daño.. tiene usted una idea de que componente pudo haberse dañado?... gracias
Yo no he abierto el mío. Pero por casulidad, recuerda que algunos componentes pueden estar en corto circuito en la entrada de la medicion. Sin batería, busca si hay corto en los terminales.
we can or can't measure capacitor on board?
Good video, good information.
Thanks bob the builder. Best regards from philippines . ,
Best regards to my viewer friends from Philippines! (I also have a friend from Philippines at Jacksonville FL, who I consider almost a brother, and I miss other friend who was a great politician from Philippines who already passed away and rest. My blessings to all of you. :-)
Very informative though I would appreciate if if it will include also interpreting the results of the test/s say, that polarized electrolytic capacitor for charging but not discharging properly or, that it's discharge is somewhat "clipped" or, that it shows a high leakage current - all indicative of a bad capacitor and (please, as would in some forums) that one does not need for that capacitor to bulge in it's head or even explode. Since you have also indicated smd capacitors (which may include those polarized tantalum capacitors), does the testing and the test results of that polarized electrolytic capacitor apply the same to that of a polarized smd tantalum capacitor or does the latter behave differently from the former? I have right now 3 brands of smd tantalum capacitors of which 2 are from AVX and NEC/TOKIN. The 1st brand behaved as expected when tested just like that of the electrolytic capacitor in say, bias-reverse-bias (charge/discharge state.). The other two, AVX and NEC/TOKIN, did not.
Ok. Thanks! I will make another video.
Sir at the end you mentioned that go to read books and dont got TH-cam but sir in Books their is no chapter or topics include where we can read how to test components.
Sir if you have any book testing equipment or devices than kindly sir share it with me I will bought soon
+abid saleem Hi! Most electronics engineering books, are written by engineers, and master in electronics who know what they are doing. Sadly for the "confusion", anybody with a free Gmail account, can upload a video with wrong information, and it is watched for millions who will learn something wrong.
My best advice, because most of you are out of English speaking countries, and some of you doesn't have formal education in electronics; I recommend to go to a main city, visit a good book store, and look for "fat" electronics engineering books, with samples and mathematical formulas. Those books are expensive. But a good advise is do not buy them in the first trip. Take information about the book title, writer, edition, and check in google if you can download it "free" in pfd format or to find it to read free in books on line. :-)
(Sadly, there is always a big separation between electronics engineering and technical repairing. One only teaches to calculate the right capacitor. But only the other teaches how to test them and remove it). I will try to make a video about books in the future. And I will ad more videos about testing too.Thank for the question.
Dear Sir I am
master in Electronics and have lots of knowledge of Electronics but testing component knowledge is not good
well said you sir
Aha! I had the same problem in the middle of the 80's. That happens because the humanity history is just starting to be written, and the technology chapters are in the process. Dear colleague, next generation depends of us to get those books. It is the reason why I started to make videos. I used to teach engineering from books to 15 students in the classroom. Nowadays, I got about 80.000 "viewers" in TH-cam, and maybe some students from it, and I am teaching technical skills for repairing.
I hope to add 3 more books to the market with some of the knowledge to apply in the workshop.
(I think the problem is because in most countries there is a Superior Education Organization who supervises very well upon Universities. But they totally ignores the technical academies and informal training schools).
Very true sir... you really touch the grib of the students....I really like your all videos and specially ur response in quick time.......GOD give u better health its my wish and pray
+abid saleem Thank you! Good bless you, and your loved ones too. We will be in touch! :-)
very good video,,,clear and cool,,,thank you for these information
Bob.. Muy interesante y educativo su video.. Excellente.. Gracias
hola, tendrás este video en español, busque en tu canal y no lo encontré, me gustan mucho tus videos son geniales y ayudan mucho a personas como yo que les gusta la electrónica como hobby.
Well done, nice video, thanks for sharing it :)
great video...appreciated seeing how to lift up a cap to test it.
+ckreitlein Thank you! The main idea was to show to test SMD caps and teach some tricks like the right polarization for non polar caps for new designers. Another video is on the way.
Can you tell me ,how to measure safety capacitor X@0V Y@0V 102M
Hi! The way to measure a capacitor is removing it from the PCBA.
@@bob.kalpon1398 I mean, how to measure safety capacitor like that one?
www.eworldtrade.com/pd/suzhouaxoe/x-y-radia-lead/174871/
Hi Bob,thanks to share your experience with all of us, i´m a total beginner in electronics field but I would like to learn more because I like challenges like finding the defect and repair it, naturally i´m not an engineer or a technician but like every other human being I have an Intelligence :)
Ok after this long introducing I would like to ask you about measurement with a multimeter of capacitors, I have bought a multimeter with capacitance function with an up limit of 200uF , my question is if I can measure capacitance of capacitors over 200uF or not, I have some polymer aluminium electrolitic capacitors with capacitance of 270uF and 470uF and the multimeter doesn´t read them, is that normal or I making a mistake????
Another question as newbie that I want to make , is possible to measure the capacitance of a capacitor without desoldering it from the PCB???? I ask because desoldering is so boring but in TH-cam I have seem some videos of users they say it´s possible and other instead that say is not possible to because you will not have the right value of capacitance, sorry for the long message..........I have my subscription to your channel and I wish you all the best for it.
Thanks
Luca
I had the same exactitude in the mid 80's. There was not any electronics school in my town, but I wanted to learn, and learn it all and to grow and to be on of the best... In 1989 I registered my first patent, and 10 years later against all the adversity I graduated as engineer. Now day's, 600.000 people watched my videos and I am able to help people like me, searching for knowledge in electronics. Don't stop, be humble and always ready to learn. I wish you the best, and welcome to the wonderful electronics world. "This is electronics. We don't work. ...we just enjoy with it". ;-)
Thanks I am just learning I'm retired and hate it so I was wanting a hobby but now I want to learn electronics and go back to work for a few more years. thanks for helping me understand resistors. 1 question Bob How do you know the Resistor is bad? Does it have to be within that range or what if its 6% over?Do I consider it bad?
Well done! You are just retiring from your job. But, life goes on, and it is just a new begining again in life. Don't stop. "This is electronics. We don´t work. We just enjoy it". :-)
If you hold the discharge resistor wire with the metal pliers (you were not holding the insulated part) and if it is 200v and charged, you could give yourself a hell of a zap...
Yes, after 30V we must use insulation. Also the discharge time should be the capacitance times the resistor times 5. Any capacitor after 35V indication must be handled carefully.
@5:00 NO. This is not true. The markings on these capacitors DO NOT indicate outside foil lead.
Hello Bob!
Is there a capacitor that be used as a fuse?There was a aluminium housing fuse with 5A 32V tolerance and blew away like an Elko but no where to find something like that.Is is allowed to replace it with the ordinary fuse?
Thanks for the info, please can you please tell me the name of that book
How can I test a low value ceramic capacitor by a multimeter ?
Hi! It has to be a multimeter with capacitance meter function. Then it will be as simple as to use a single capacitance meter. If your multimeter doesn't have the function, then there are more step method as applying ac voltage with a serial resistor to a non polarized capacitor, and calculate Xc. If the capacitor is polarized, then connect two capacitors in serial (-+,+-) with the centers pointing inside, plus a serial resistor to the AC source to calculate Xc. You will have to look for the Xc formula, but the experiment will help to learn a lot. (Be careful, because capacitors calculations must always be done with Peak or Peak to Peak Voltage). For your experiment you will look for AC RMS to Peak to Peak Voltage convention, RC serial calculation, RC impedance, and Xc capacitive reactance calculations from most good basic electronics or electric principles books.
Bob. Kalpon
Thank you Bob!
Just the info I was looking for.
You'r welcome! I have more material without editing. I hope I can make the 2nd video soon. :-(
Awesome video. Learning a lot. Funny thing is I thought he said MFs at 7:22
Its good videos and very useful.
Hello Bob, thank you so much for your video. I enjoyed it a lot.
Thank you so so so much. The book is the best place to learn from indeed
Hi Bob very good and informative video. I have a question: will you make a video about testing transistors and ICs ? Thanks
nice video Bob, regards from argentina
+Nvision250 Gracias! Ese es un pais, que siempre he desado visitar. :-)
Best learning viedo i had ever
Great info, but if you came here to TEST a cap SKIP to 11:00
So I did, and learned nothing except how to lift one end of a capacitor (which I already knew). The sound is so bad anyway I didn't know what point the chap was making.
Hi Mr Bob.Very instructive but you have not tested any capacitor after you have lifted one side of them + it would have been very interesting to show the difference between "open" and "short" at the same time
thank you Bob , i will looking for new video from you soon
great English . great demo as well thanks
how can testing the diffrent thyristors
Very useful video but the way you remove smd capacitors from the pcb is not properly correct. In the second case it is quite clear you are lifting one of the land from the laminate surface. Ciao!
Hi! For SMD capacitors we can use hot air to remove it, soldering iron with special tip and connected to a soldering station for proper one side lift up, or soldering iron with tweezers connected to a station for removing the biggest SMD. Some people like more to remove them with hot air. I was a process engineer in an American SMD capacitors industry, and I know no one rework process is too healthy for them, and in that case I rather to lift up one side.
I respect your opinion, but no as a teacher, but as a process engineer who made the SMD capacitor from A to Z, and certified for quality in a ISO manufacturing, I avoid all the over heating in repairing procedures.
Unfortunately the lighting and camera close up is not efficient or clear. Sorry for the comment or criticism but it's TRUE.
Get the appropriate equipment for soldering removing and installing surface mount capacitors.
came here to learn how to test capacitors....end up watching the whole video and learning sth else 😌😌
tq for video..learn more about capasitor..
How ceramic capacitor working in power amplifier
please tell ways to test ps caps esr
thank you lot's you are right ,god bless you and your familly.
Very nice explanation.thanks
thanks for good info about capacitor , you can teach very well.
in some other dialect besides English maybe, don't folks review there work before posting them? I suppose no one hears their own accent but someone should be giving editorial review input prior to posting.
Thanks Ahmed. Teaching is always a hard task to do. Teaching electronics involves more than pedagogic knowledge or an engineering profession. It is more through the years of experience, where we learn more about student's needs. Education is a stair process. Students learn more and faster as we add more steps and deepest bases. It is the right way to bring a student from zero to the highest level of knowledge. I learned to listen to people and to teach in function of their needs. I am not the best teacher or engineer because I have to enforce to make it for four European languages, for different knowledge levels or professions. In this Channel, I teach only very basic electronics in two languages.
Try to be a good student to learn always more. And remember, the only way to measure success is by results. More than half Million people watched my videos and gave already a good feedback to stay on in this TH-cam Channel. This Channel is for people like you an me, from all the world, who search knowledge to be better and to be success. Thanks for writing, and sharing your opinion. Stay close! I there is a group of colleagues, students and friends who are always in touch, and I never forget about them in this Channel.
Great video! keep up the work, nice work
Great explanation. Thanks.
King regard for you..👍👍👍👍
jump right to 11:00 to learn how to test the cap.
@all motor That's testing continuity. Wrong part of the video, buddy.
it makes no sense to remove the capacitor before testing it. i need to test it to see if it needs replacement
Thank you for being real.
what is F 2n 20n 200n 2u 20u
Excellent info, thank you! Helped me diagnose a busted 3DS (due to water damage :( )
+Joseph Gosselin (Popple) Hi! I spoke about how to treat electronics after water in my video:
th-cam.com/video/ePXSxXqLTA0/w-d-xo.html
(Use high degree alcohol, a soft brush, and pressure air to rinse it. Other ways, in a few weeks it could become as the laptop in my video:
th-cam.com/video/-Gh_LXvhap4/w-d-xo.html
Very well explained
15:22 The most intelligent thing ever said on TH-cam.
Awesome video about capacitors thanks a lot!
Awesome tutorial, thank you
NICE VIDEO THANKOU FOR THE INFOS .MY FREND . COME TO GREECE SOME TIME .AND SPECIFICALY NOW WHERE IS SUMMER
Thank you! Sure we will go. It will be nice to have a friend there. Please write to my email.
you have Bob 1 frend here . yes and i am in halkidiki .xexexe.... your email i dont know it Bob .for write there.
kalponelectronics at gmail... It is in the Channel description. :-)