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 🙏👍👍👍
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.
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. RUclips 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 RUclips 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. :-)
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! :-)
+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.
+Joseph Gosselin (Popple) Hi! I spoke about how to treat electronics after water in my video: ruclips.net/video/ePXSxXqLTA0/видео.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: ruclips.net/video/-Gh_LXvhap4/видео.html
+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, 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.
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. :-)
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
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.
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.
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?
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.
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 RUclips. 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! 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 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 RUclips 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". :-)
+Brett Stafford Thank you! You are welcome. I am working in a video about troubleshooting with SMD devices, and a step by step procedure for electronics fixing. (Updating my old schooling from the 80's to now day's technology).
+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)!
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 RUclips 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 RUclips, 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.
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
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.
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.
Hola bob, excelente video. sabes mi inglés no es muy bueno, así que no entendí todo el video, yo estudio electrónica y tus videos me ayudan mucho a entender muchas cosas que no entiendo en la escuela, y me gustaría pedirte el favor de que si podrias ponerle audio en español a este video, de antemano muchas gracias
Наука
this info has really helped me. I love those words of encouragements at the end of the video.
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
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.
...Keep the videos coming! This one was great! I'd like to know more about testing with a Multimeter and other testing equipment
"Thank You", thank you very much. Your presentation was REALLY good 😎
Congratulations! A very useful and practical lesson for us who take the theory to the bench.
Very well explained Bob, thanks from Macedonia!
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. :-(
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. RUclips 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 RUclips 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. :-)
Bob.. Muy interesante y educativo su video.. Excellente.. Gracias
Hello Bob, thank you so much for your video. I enjoyed it a lot.
Thx and much appreciated for sharing this video.
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
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! :-)
"and some have the shape of pillows" 😂😂 love it
..
I loved it when he said that IT COULDNT be explained any better 😁😁😁😁
Awesome video about capacitors thanks a lot!
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.
Good job - very professional and quite detailed
Most exellent demo sir.well done.keep up the great work.
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.....
@@mr.mojorisin9999 cheers g
Great video! keep up the work, nice work
Thank you very much. This was really helpful!
+michor10 You are welcome!
Thanks for the detailed video.
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:
ruclips.net/video/ePXSxXqLTA0/видео.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:
ruclips.net/video/-Gh_LXvhap4/видео.html
thanks a lot I learned a lot from this video
why does the alternator fail
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.
Very instructive video, look forward to the watching others.
:-! :-! L
Mh6
n
very good video,,,clear and cool,,,thank you for these information
Thank you so so so much. The book is the best place to learn from indeed
thank you Bob , i will looking for new video from you soon
Cool stuff. Thank you.
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
great English . great demo as well thanks
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.
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. :-)
Best learning viedo i had ever
out standing i just learn how to do this now thank you
Awesome tutorial, thank you
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
best information video ever nice vid bud
Great explanation. Thanks.
Muchas gracias por compartir tus conocimientos.
+Israel Mejía Con gusto. Gracias a ti por verlo. :-)
Hi Bob very good and informative video. I have a question: will you make a video about testing transistors and ICs ? Thanks
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 ?
You look like Muhammad Ali ! I am a beginner and love your videos I lie in Florida Thank You
super helpful!
Well done, nice video, thanks for sharing it :)
do you think ESR testers are accurate for testing caps on the boards ?
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.
tnx bob.great video
THANK YOU VERY MUCH!!!
Hello nice video almost helpd me if on a capacitor is (M 3a 471 OJ) how can I find out please help
thanks for making such vid
Thank you for video
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.
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?
excellent tutorial bob
Thanks! :-)
good
Awesome video. Learning a lot. Funny thing is I thought he said MFs at 7:22
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.
Good video, good information.
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 RUclips. 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) :-)
Thank you so much!
thanks it is really helpful
awesome, super super helpful
Very nice explanation.thanks
thank you lot's you are right ,god bless you and your familly.
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. ;-)
Its good videos and very useful.
Can you use a light bulb to discharge the capacitor so that you can easily tell when it's finish?
came here to learn how to test capacitors....end up watching the whole video and learning sth else 😌😌
Thanks for the info, please can you please tell me the name of that book
King regard for you..👍👍👍👍
TNX MUCH FOR THE VIDEO...
Thank you very much :)
+yassin mounamir Your welcome! :-) ...thanks by watching.
+Bob. Kalpon
you are great.
nice video Bob, regards from argentina
+Nvision250 Gracias! Ese es un pais, que siempre he desado visitar. :-)
Thank you very much!
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 RUclips 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". :-)
tq for video..learn more about capasitor..
Hello, Thank you for video
Thank you for being real.
Nice vid thanks for the info
+Brett Stafford Thank you! You are welcome. I am working in a video about troubleshooting with SMD devices, and a step by step procedure for electronics fixing. (Updating my old schooling from the 80's to now day's technology).
+Bob. Kalpon Awesome looking forward to it
What is the defference between black color capacitor and blue color capacitor but same resistance 100uf 16v is this same or have difference??
+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)!
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 RUclips 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 RUclips, 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.
thanks broe you are good teacher
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
Thanks Bob!
good tutorial thanks
Very well explained
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.
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.
Hola bob, excelente video.
sabes mi inglés no es muy bueno, así que no entendí todo el video, yo estudio electrónica y tus videos me ayudan mucho a entender muchas cosas que no entiendo en la escuela, y me gustaría pedirte el favor de que si podrias ponerle audio en español a este video, de antemano muchas gracias
Ok. Dame tiempo. Gracias por escribir.
+Bob. Kalpon Muchas gracias, eres el mejor
thank you so much for your lecture a bout capacitors
+naseem aldano You are welcome!
Great video Bob!! Thanks for sharing your knowledge, 79, joe-k4jga
can I test and measure without unsolder from the board or are number always wrong like that....?!
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.
nice one. Thanks!
Thanks very much for your advice
we can or can't measure capacitor on board?
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. :-)