One of the best parts of a site like this (you tube) is that no matter how thoroughly someone covers a topic there will be someone out there who will have an answer for the smallest detail that was missed or a better way to word it so even the dimmest amount us can understand. It really adds to most videos and helps complete whatever discussion or tutorial is being presented. This fellow did a fine job of explaining these circuits all by himself but the comment section dots the I’s and crosses the t’s.
I'm a student currently studying EE and I always felt my hands on repair skills were lacking. This channel is so amazing thanks a lot for sharing your knowledge with us :D
Hello from Australia. My name is Andrew and I'm 62 and I've been around electronics all of my life [I got my first shock at 4 years of age]. This was a great video because I didn't realize how much I had forgotten over the years. I love valve sets and I own a PrimaLuna HP Integrated amp with 6 12AU7s on the Pre-amp side and 8 EL34s on the output side. These amplifiers reek of good taste. All of the transformers are toroidal and wound in house. This amp runs point to point wiring using Adaptive Auto Bias. The people who wire these amps are artisans. They use Tachman resisters and Nichicon Electrolytic Capacitors. They use standard but great bridge rectification and high quality chokes to eliminate ripple. My Technics SL1200MK2 is a new Pro turntable and has never been in a club fitted with an Ortofon Blue Cartridge. It is a MM using a nude stylus and runs through a Cambridge Pre-Amplifier then to Aux Input 1. My CDJ PRO Player runs to a Cambridge DAC and it has its own input marked on the selector switch. It has an Alps Volume Control and the selector switches are actually relays that close leaving the others open to avoid bleed from other components. The valve sockets are attached to the chassis and the power tubes are surrounded by pencil size holes to suck heat away from inside.They are a stunning amplifier. My Wharfedale speakers sound like a massive soundstage and a REL sub kicks in for home cinema. I love your videos. Keep them coming. Cheers from OZ, Andrew.
You didn't mention tantalum capacitors which are physically small, have large capacitance values with low voltage ratings, and have a tendency to short out because they grow internal whiskers when they get older. They often have the physical appearance of an inverted droplet. You will often find these in older mother boards and circuit cards mainly as filter capacitors. Great video! I have been doing repairs professionally for more than 50 years and this is the best video I've ever seen on this subject. Thanks for all the information, I'm sure it will be most helpful to many.
They are often yellow and are marked for their (+) anode, or a stripe. Connecting them backwards can lead to catastrophic results. In surface mount they are a tall rectangle of orangish yellow or black. The black ones look exactly like SMD diodes, so take care to look for the silkscreen on the PCB. C will be a capacitor and D or CR will designate a diode.
This is a top notch explanation of capacitors - you really do have a gift for explaining things in simple terms in a no nonsense way - I wish I had this explained to me 40 years ago while learning about integrator and differentiator circuits the hard way, on my own and out of a book with no one around who could steer me in the right direction... years later I remember the capacitor plague all too well,I seem to remember reports at the time stated it was down to bungled espionage involving a stolen formula with the last page missing, so it was approximated by the scientist that stole it from rubycon and sold it to a chinese manufacturer and we all know what happened after that...
That's what I remember as well. I had just built a new computer with a Pentium 3 processor which was reasonably fast in 2001 when I found out about the 'faulty manufacturing' and, of course, I missed the warranty period by a few weeks (just long enough to really piss me off with the manufacturer) Sure enough, all the 6.3v caps bulged (I think about 25 or so) Never did get around to re-capping board even though I bought better quality replacements
@@maxwang2537 hundreds of thousands of circuit boards failed due to capacitors leaking. I stopped using my computer 'just in time' to prevent catastrophic failure
@@maxwang2537 As stated somewhere in the vid or comments it was due to industrial espionage. The 'new' capacitor had all the specs except the electrolyte so that was an educated guess which turned out to be wrong leading to catastrophic failures all around the world. I read about it in a computer magazine so decided to check my motherboard and found damage before complete failure.
Greetings from Australia :-). Great video, as usual. The only one tiny technical thing... Correctly functioning capacitor (i.e NOT internally electrically leaking) is blocking ALL THE CURRENT - BOTH DIRECT AND ALTERNATING. There is NOT any electrical connection inside. The only difference is, that it REPLICATES the alternating current on the other side, but it CAN"T replicate the direct current (the phenomenon used in signal filtering, as it almost doesn't replicate the noise but the main signal). That's why conventionally we say that it LETS THROUGH THE ALTERNATING CURRENT but blocks the direct current. This is an important point in understanding the main failure of a capacitor. Everything starts when capacitor starts to leak a current from one plate to the other through a dielectric. Delayed charging (change in frequency) and lower maximum charging, as it loses some charge to the other side, becoming virtually a resistor, increasing internal temperature. This may lead to increased internal pressure in electrolytic capacitors, leading to bulging, opening the top or popping out the bottom, or even explosion in extreme situations..
That's a good clarification and what I thought. Being a mechanic I didn't want to look stupid when there are people far more knowledgeable than me watching and commenting
WOW I'VE LEARNED TWO NEW THINGS FROM THIS VIDEO NOW. THANK YOU FOR THAT INFO. 🇮🇪👍 P.S. I knew about that part of the cap basically becoming a resistor and why it does. But didn't know about AC current part you mentioned. So thanks again your a star 🌟 my friend 👍😉
Awesome, thanks for the clarification. It was really bugging me when somehow DC passed but AC didn't - didn't make sense to me, but now it's clear that nothing passes - it just mimics AC on the other side, which makes perfect sense. Thanks!
Thanks, for the simplest way of explaining what and how the capacitors work for aspirant technicians. Even to us with more than 25years of experience in consumer electronics fields- this serves as some kind of revision and reminder of basic concepts. Much appreciated indeed.
I used to check caps by setting my multimeter to 200k, place the probes on the legs of the capacitor and the reading will either go up or down depending on the polarity. flipping the probes will cause an opposite effect; so if the reading was going down before, it will now Rise at the same speed. This indicates a good component! I've recently invested in a good ESR meter and they really are a godsend! Thanks for making these videos, they are so easy to understand.
Inside the fuel pump relay on many older (1980's to mid 2006 ish) Suzuki motorcycles is a small cap that con only be checked with an analog meter as 'auto-ranging' isn't fast enough to react. The service manual only says 'needle deflects' and often doesn't make full scale. Using auto-ranging meter always shows the relay as 'bad' (no difference between a $5.00 HF or $300 Fluke)
I thought I knew a little about how capacitors are used but found out I know far less than I thought. Now, I really want an ESR mete reven though I've never done electronic repairs for a living. 👍
I just fixed my 1996 Magnox 27" TV by changing 4 caps. I found the bad ones using a multimeter set on diode/continuity/beep. I alternated each cap leg listening for a quick beep while alternating cap legs (in circuit aka while on the board). Anything but a quick beep in both polarities means a bad cap. I found 4 bad. Replaced them with 4 caps that checked out from donor TV. Bam. Working TV. I actually cant believe it worked. This is the first time I 've done anything like this. My thanks to all the electronics people here on UA-cam. Now I can watch some old movies and games in retro nirvana.
I used to make Lyden jars. I was showing a friend of mine how the Lyden jar can keep a high voltage charge on it for a long time. I grabbed the cathode arm and brought it to the anode but my thumb got in the way and the jar discharged trough my thumb. I had to go to the hospital. Frank
As a EE I am enjoying your work! We learned a TON of theory, but I always felt that we needed more "break/fix" type knowledge. Thank you Richard for creating this channel and taking the time to create vids. As an aside, we studied the theory of caps, but I have always wanted to know how the chemistry of the electrolyte comes into play. Electrochemistry is a completely different box of frogs.
37:40- Funny you mention reconditioning old capacitors. I am 'forming' the capacitors in my 2400 watt-second studio strobe flash power packs since they have been sitting unused for months. They are high quality Japanese units that are from the 1980s and work flawlessly. I am unable to control the charge voltage but I am able to use the lowest output setting for the beginning of the 'forming' session usually a couple hours before actually discharging them by cycling the light heads. They have 'photo' rated capacitors that are very high speed. I intend to fix some Stereo amplifiers but would never consider monkeying with these high joule power packs. Dr. Balcar who made some of the finest studio lighting units was electrocuted at his workbench working on a power pack. That's enough warning for me.
Your ESR example is showing a resistor in parallel which is actually equivalent to leakage. ESR is Equivalent SERIES resistance with the "resistor" in line with the capacitor.
hi, currently working through the starters playlist,,, this was a fantastic lesson ,so much so i'll watch again, because it was fascinating withs lots to absorb🙂🙂🙂
Absolutely the best teacher on youtube I have a Q, how solid state caps fail when they get higher voltages, still loosing their capacitance or higher esr or something else? thanks
I follow with very passion his explanation and I hope to get able to repair small electronic device like the flow regulator (RL30 GC COFFEE 230 Vac by GICAR) of my coffee machine. Thank you very much for you lessons! 🙏
Useful method for accurate DC leakage current measurement is to hook up the DUT in series with a 10/20k resistor to a DC bench supply and measure Vdrop ax the resistor whilst keeping an eye on the timer. Voltage should drop & stabilize within 5/10minutes for standard electrolytic caps, and even quicker for purpose made low leakage caps. Also, electrolytics' data sheets contain small print mentioning lifetime cannot exceed 15 years due to rubber seal deterioration. MLCCs also exist in THT format and are often used for de-coupling of power rails for example, in X7R guise. More demanding locations usually feature C0G version.
Thank you, 😊 I didn't know that discharging a cap with a screw driver was a bad idea 😬 I'm definitely going to use the tip you showed here anymore 😉.. Nice one mate. I Always say if you don't learn something new every day then that day was a waste of time 😉 so thank for that.
I’ve got more than 100 mainboards in my “to re-cap” pile…I guess there’s no excuse to not be getting on with it now 😆 Edit: Fu*king hell Richard, you’ve got almost 5000 subscribers already, your channel is flying!
I've only got one mobo to do but not sure if it's worth it as it's been obsolete for a long time. Probably a good idea if only to practice my de-soldering/soldering
@@jonchapman6821 True, I have a bunch of games that will play on it as well. My 6yr old grandson has been looking at some 'driving' games and I still have the Microsoft wheel and pedals that haven't been used in ? years (20+)
25:25 - This meter injects a 100k signal into the circuit to be measured. Have you ever come across a circuit that was potentially damaged by this (e.g., microprocessor chip)?
@LearnElectronicsRepair,I'm just learning electronic circuits, but if you could help me by explaining if capacitors block dc and allow ac,why does the large capacitors come after the bridge rectifier in the switch mode power supplys,hasn't the ac signal already became dc at that point,and if so how is the dc being accepted by that large capacitor to be used afterwards?
Hello, thank you for your UA-cam video. I am wondering if capacitors can charge before fully having discharged. Does AC blocks discharging or does it add to the voltage of a discharging capacitor ? Thank you in advance.
Hi could you do a beginners video on what a short circuit is (For dummies) Also do you do phone repairs maybe doing some videos on iphone chips capacitors/resistors might be beneficial as well
At 2 minutes you drew a symbol calling it a polarized electrolytic capacitor. I was taught that it was a non polarized electrostatic capacitor, but the curved side was there to indicate the outer side of the capacitor’s foil. This was to simply be placed towards the chassis or any ground traces. That way if any accidental physical shorts there would not be as big of calamity
Hey! Ok, I think this is because I am new… like very new to this, but can you explain what you mean by noise between 11:00-12:30. Im having a rough time understanding this
Thank you for such an extensive and very useful explanation, I thought I knew everything about capacitors and here a pleasant surprise, I am gaining a lot of very useful knowledge, thank you again for taking the time to explain how it all works ps. Could you ever make a series on how to read schematics and explain how some circuits work? I know that this is a topic of a river, but maybe someday you will find time to talk about it at least a bit, thank you Łukasz, greetings from Poland, sorry for my English🙏🙏👋👋👋👋
There was also an era in the late 90's to early 2000's, where electrolytic surface mount caps were bad. These were predominantly used in video cameras, and had poor quality base rubbers, that leaked very early in their life. initially very hard to detect as damage and spillage was under caps (tracks eaten away). Whenever you come across any electrolytics that leak from the base, be sure to thoroughly clean and neutralize the electrolyte, especially on multi layer pcb's. Many of those repairs we did, involved tracing and re linking eaten away tracks in the camera's, which is very tedious and time consuming work. Ex technician, some 18 years domestic electronics thru to industrial comms engineering companies.
The electrolyte is absolutely not the dielectric in an electrolytic capacitor. The aluminum or tantalum oxide is the dielectric, the electrolyte acts as one of the plates, with the metal film or powder being the other plate.
I have a question.. I am always tinkering with old motherboards and video card. Just about all of them have the aluminum electrolytic Capacitors. How do determine which solid to use in place of the aluminum electrolytic Capacitors?
Hi Richard, I have been binge watching your vids and love your teaching style. I'm trying to educate myself on electronics repair and had an idea for a project, would love your thoughts. I would like to make a basic tool to read the voltage across a capacitor and drain drain it on command. My understanding so far is that different resistors are appropriate for different voltages so I wondered if it would be possible to apply the correct resistance intelligently in some way either with a microcontroller of some sort or with clever circuit design. Would love any feedback and please feel free to come up with something yourself that newbies like me could all learn from, might be an interesting video. My assumption is that this tool does not have much in the way of demand otherwise I'm sure my google searches would have come up with something.
Hello Sir and thank you so much for those very clear and live explanations you give us for free! I have a subquestion to ask you, sorry if it sounds obvious. Because I'm french, I think I missundestood what you said at around 38:15. Are the eletrolytics the ONLY ones that I can test with the ESR or are all condensators usable with this tool ? (is it ok with Ceramics, tental...) - Thanks a lot for you answer and once again for your pedagogy! Alex (sorry about my poor english)
Thanks for this video, I understood the first one of the series on reistors a lot more, found this too much to take in and got very confused. Not really sure about a lot of what was talked about, but i'm going to keep watching and probably watch this one again at a later date.
@32:45 does this mean that you drew 4 anodes and 3 kathodes = inequal pairs? I tried to look structural pictures from google but they're way beyond my 2-year 90's electrician school understanding.
I would like to know if I need a capacitor type, ohm and capacitance for a cb radio on my school bus the radio loses power when the yellow light button is pressed thank you for your time
Another great video. You're really helping me to bolster my basic understanding of electronic. May I ask, are you originally from the town I grew up is, Stoke on Trent? Your accent sounds so familiar.
The problem that I have with learning stuff like this is that its SO MUCH information and I have absolutely no internal base to put it or attach it to anything else I know. It's just a bunch of words with no associations.
Great series... I'm enjoying and learning much from them as I work my way through them all. With the ESR meter, what are your thoughts on one of the multi-testers like an Aideepen T7 TC-T7-H (transistor, diode, capacitor ESR, etc.)? Is it good enough for a general hobbyist or do you think a dedicated ESR like the MESR-100 is worth the buy? Trying to spend my money in the right places and if a multi-tester works, then it is always preferred for me at least. Tx!
Not really, you need to take the capacitors out to measure the ESR effectively. Often the faulty capacitors are visibly bad but they can look perfectly OK and still have very bad ESR so the circuit will not work properly or even work at all. This is where the ESR meter is so valuable, otherwise the only other way to find those faulty capacitor is by substitution You can use the ESR meter for finding short circuit MOSFETs in VRMs, and also to measure the value of inductors. I've shown the ESR meter used to trace short circuits in several videos
I found a regular meter works good on testing if the capacitor is good or bad by see if the capacitor charges and discharges by switching the leads both ways if it doesn't its bad even if the capacitor reads the right capacity it needs to pass this test thanks
For info on capacitor replacement the best place to go is the free forum www.badcaps.net/forum
Whats your name on the badcaps forum. I don't think you've ever said
Can you draw bigger please?
Can you explain again what esr is?
One of the best parts of a site like this (you tube) is that no matter how thoroughly someone covers a topic there will be someone out there who will have an answer for the smallest detail that was missed or a better way to word it so even the dimmest amount us can understand. It really adds to most videos and helps complete whatever discussion or tutorial is being presented. This fellow did a fine job of explaining these circuits all by himself but the comment section dots the I’s and crosses the t’s.
One of the best teachers on youtube. Thank you.
Now you are making me blush 😊
@@LearnElectronicsRepair its true.
I agree 👍 this guys is really easy to listen to and has great info in his videos, I just found his channel a few day back. And I'm hooked.
Yep, that lilting British accent.
Im strait by the way.
I'm a student currently studying EE and I always felt my hands on repair skills were lacking. This channel is so amazing thanks a lot for sharing your knowledge with us :D
WOW. The best tutorial I ever seen. 10 STARS. You are GREAT.
Hello from Australia. My name is Andrew and I'm 62 and I've been around electronics all of my life [I got my first shock at 4 years of age]. This was a great video because I didn't realize how much I had forgotten over the years. I love valve sets and I own a PrimaLuna HP Integrated amp with 6 12AU7s on the Pre-amp side and 8 EL34s on the output side. These amplifiers reek of good taste. All of the transformers are toroidal and wound in house. This amp runs point to point wiring using Adaptive Auto Bias. The people who wire these amps are artisans. They use Tachman resisters and Nichicon Electrolytic Capacitors. They use standard but great bridge rectification and high quality chokes to eliminate ripple. My Technics SL1200MK2 is a new Pro turntable and has never been in a club fitted with an Ortofon Blue Cartridge. It is a MM using a nude stylus and runs through a Cambridge Pre-Amplifier then to Aux Input 1. My CDJ PRO Player runs to a Cambridge DAC and it has its own input marked on the selector switch. It has an Alps Volume Control and the selector switches are actually relays that close leaving the others open to avoid bleed from other components. The valve sockets are attached to the chassis and the power tubes are surrounded by pencil size holes to suck heat away from inside.They are a stunning amplifier. My Wharfedale speakers sound like a massive soundstage and a REL sub kicks in for home cinema. I love your videos. Keep them coming. Cheers from OZ, Andrew.
The main uses of capacitors are very well explained Thank you
Thanks! I fixed my 1965 Mopar radio!!! I am so happy.!!
You didn't mention tantalum capacitors which are physically small, have large capacitance values with low voltage ratings, and have a tendency to short out because they grow internal whiskers when they get older. They often have the physical appearance of an inverted droplet. You will often find these in older mother boards and circuit cards mainly as filter capacitors. Great video! I have been doing repairs professionally for more than 50 years and this is the best video I've ever seen on this subject. Thanks for all the information, I'm sure it will be most helpful to many.
They are often yellow and are marked for their (+) anode, or a stripe. Connecting them backwards can lead to catastrophic results. In surface mount they are a tall rectangle of orangish yellow or black. The black ones look exactly like SMD diodes, so take care to look for the silkscreen on the PCB. C will be a capacitor and D or CR will designate a diode.
Thoroughly enjoying this series, you're so easy to understand. Great teacher.
Thanks!
Agree 100%
This is a top notch explanation of capacitors - you really do have a gift for explaining things in simple terms in a no nonsense way - I wish I had this explained to me 40 years ago while learning about integrator and differentiator circuits the hard way, on my own and out of a book with no one around who could steer me in the right direction... years later I remember the capacitor plague all too well,I seem to remember reports at the time stated it was down to bungled espionage involving a stolen formula with the last page missing, so it was approximated by the scientist that stole it from rubycon and sold it to a chinese manufacturer and we all know what happened after that...
I don’t know what happened next. Very curious. Can you please elaborate.
That's what I remember as well.
I had just built a new computer with a Pentium 3 processor which was reasonably fast in 2001 when I found out about the 'faulty manufacturing' and, of course, I missed the warranty period by a few weeks (just long enough to really piss me off with the manufacturer)
Sure enough, all the 6.3v caps bulged (I think about 25 or so)
Never did get around to re-capping board even though I bought better quality replacements
@@maxwang2537 hundreds of thousands of circuit boards failed due to capacitors leaking. I stopped using my computer 'just in time' to prevent catastrophic failure
@@1crazypj thanks for your reply. But the story after that , or as a whole, still remains mysterious to me. And I’m curious.
@@maxwang2537 As stated somewhere in the vid or comments it was due to industrial espionage.
The 'new' capacitor had all the specs except the electrolyte so that was an educated guess which turned out to be wrong leading to catastrophic failures all around the world.
I read about it in a computer magazine so decided to check my motherboard and found damage before complete failure.
Greetings from Australia :-). Great video, as usual. The only one tiny technical thing... Correctly functioning capacitor (i.e NOT internally electrically leaking) is blocking ALL THE CURRENT - BOTH DIRECT AND ALTERNATING. There is NOT any electrical connection inside. The only difference is, that it REPLICATES the alternating current on the other side, but it CAN"T replicate the direct current (the phenomenon used in signal filtering, as it almost doesn't replicate the noise but the main signal). That's why conventionally we say that it LETS THROUGH THE ALTERNATING CURRENT but blocks the direct current. This is an important point in understanding the main failure of a capacitor. Everything starts when capacitor starts to leak a current from one plate to the other through a dielectric. Delayed charging (change in frequency) and lower maximum charging, as it loses some charge to the other side, becoming virtually a resistor, increasing internal temperature. This may lead to increased internal pressure in electrolytic capacitors, leading to bulging, opening the top or popping out the bottom, or even explosion in extreme situations..
That's a good clarification and what I thought.
Being a mechanic I didn't want to look stupid when there are people far more knowledgeable than me watching and commenting
WOW I'VE LEARNED TWO NEW THINGS FROM THIS VIDEO NOW. THANK YOU FOR THAT INFO. 🇮🇪👍
P.S. I knew about that part of the cap basically becoming a resistor and why it does. But didn't know about AC current part you mentioned. So thanks again your a star 🌟 my friend 👍😉
Awesome, thanks for the clarification. It was really bugging me when somehow DC passed but AC didn't - didn't make sense to me, but now it's clear that nothing passes - it just mimics AC on the other side, which makes perfect sense. Thanks!
Your videos are fantastic. Easy to understand and a great refresher!!
These tutorial videos are amazing
This UA-cam channel + How to Diagnose and Fix Everything Electronic, Second Edition = Fix everything Electronic course for nearly free
Thanks, for the simplest way of explaining what and how the capacitors work for aspirant technicians. Even to us with more than 25years of experience in consumer electronics fields- this serves as some kind of revision and reminder of basic concepts. Much appreciated indeed.
Your videos are the most greatest videos on youtube. Thank you very much Sir.
I used to check caps by setting my multimeter to 200k, place the probes on the legs of the capacitor and the reading will either go up or down depending on the polarity. flipping the probes will cause an opposite effect; so if the reading was going down before, it will now Rise at the same speed. This indicates a good component! I've recently invested in a good ESR meter and they really are a godsend! Thanks for making these videos, they are so easy to understand.
Inside the fuel pump relay on many older (1980's to mid 2006 ish) Suzuki motorcycles is a small cap that con only be checked with an analog meter as 'auto-ranging' isn't fast enough to react. The service manual only says 'needle deflects' and often doesn't make full scale. Using auto-ranging meter always shows the relay as 'bad' (no difference between a $5.00 HF or $300 Fluke)
Good tip. God I'm learning loads here today. Thank you 🇮🇪👍 and I'm must invest in an ESR meter myself.😉
Absolutely brilliant, wish I had you as a teacher all those years ago at college. Thank you .
What a fun way of learning electronics. People can always learn the math later when they need it. Please keep making these :)
This comment motivates me to learn, thank you :)
Looking forward to watching this keep them coming please love this series great teaching tool.
Thank you - I'll try to publish one a week in this series, on Fridays, as long as work does not get in the way.
I thought I knew a little about how capacitors are used but found out I know far less than I thought.
Now, I really want an ESR mete reven though I've never done electronic repairs for a living.
👍
As allways perfect! Thank you very much.
Thank you very much for taking time to share this information 😘😘😘👍👍👍👍👍❤️❤️❤️❤️🌷🌷🌷🌷
thanks alot this is really hands on experience not just talking like 99% out there
I just fixed my 1996 Magnox 27" TV by changing 4 caps. I found the bad ones using a multimeter set on diode/continuity/beep. I alternated each cap leg listening for a quick beep while alternating cap legs (in circuit aka while on the board). Anything but a quick beep in both polarities means a bad cap. I found 4 bad. Replaced them with 4 caps that checked out from donor TV. Bam. Working TV. I actually cant believe it worked. This is the first time I 've done anything like this. My thanks to all the electronics people here on UA-cam. Now I can watch some old movies and games in retro nirvana.
Excellent explanation. Been struggling with coupling and decoupling terms.
I used to make Lyden jars. I was showing a friend of mine how the Lyden jar can keep a high voltage charge on it for a long time. I grabbed the cathode arm and brought it to the anode but my thumb got in the way and the jar discharged trough my thumb. I had to go to the hospital.
Frank
This is really great. I'm starting to work my way through your vids in my spare time. Good stuff.
As a EE I am enjoying your work! We learned a TON of theory, but I always felt that we needed more "break/fix" type knowledge. Thank you Richard for creating this channel and taking the time to create vids. As an aside, we studied the theory of caps, but I have always wanted to know how the chemistry of the electrolyte comes into play. Electrochemistry is a completely different box of frogs.
Learned so much from you, Thank you for your priceless videos
37:40- Funny you mention reconditioning old capacitors. I am 'forming' the capacitors in my 2400 watt-second studio strobe flash power packs since they have been sitting unused for months. They are high quality Japanese units that are from the 1980s and work flawlessly. I am unable to control the charge voltage but I am able to use the lowest output setting for the beginning of the 'forming' session usually a couple hours before actually discharging them by cycling the light heads. They have 'photo' rated capacitors that are very high speed. I intend to fix some Stereo amplifiers but would never consider monkeying with these high joule power packs. Dr. Balcar who made some of the finest studio lighting units was electrocuted at his workbench working on a power pack. That's enough warning for me.
Great video and series, can't wait for the next one,
Nice video. I am a Chemical Engineer and am trying to learn some of this stuff and you are a gifted teacher.
I am really enjoying your explanations. Keep the videos coming valuable information.
Your ESR example is showing a resistor in parallel which is actually equivalent to leakage. ESR is Equivalent SERIES resistance with the "resistor" in line with the capacitor.
hi, currently working through the starters playlist,,, this was a fantastic lesson ,so much so i'll watch again, because it was fascinating withs lots to absorb🙂🙂🙂
Easy to understand and you covered a lot of ground. Thank you A+++
This was an extremely helpful and informative video! Thank you for this
Extremely thorough, answered all my questions and much more..
Excellent series of videos. Great detail presented clearly.
Great lesson as always!
Absolutely the best teacher on youtube
I have a Q, how solid state caps fail when they get higher voltages, still loosing their capacitance or higher esr or something else?
thanks
i could listen to you for ever. thx alot
Top content, just a thought.... given the prominence of your hands, keep them looking great.
new subscriber, there's no better teacher out there
Thanks for putting the time into this video. It's such a great summary.
sir your video is really helpful please make a video about impedance testing in your all you need to know series . thank you again
I follow with very passion his explanation and I hope to get able to repair small electronic device like the flow regulator (RL30 GC COFFEE 230 Vac by GICAR) of my coffee machine. Thank you very much for you lessons! 🙏
Good explanation, keep up the good work! How do you find the correct value of an MLCC if you wanted to replace it?
Daz tinkers You mean if the original one is faulty and you can't read the value with a capacitance meter?
@@LearnElectronicsRepair yes sir, I appreciate you don't always need to replace a faulty one but it'd be useful to understand how to find it
Same question from me
Useful method for accurate DC leakage current measurement is to hook up the DUT in series with a 10/20k resistor to a DC bench supply and measure Vdrop ax the resistor whilst keeping an eye on the timer. Voltage should drop & stabilize within 5/10minutes for standard electrolytic caps, and even quicker for purpose made low leakage caps. Also, electrolytics' data sheets contain small print mentioning lifetime cannot exceed 15 years due to rubber seal deterioration. MLCCs also exist in THT format and are often used for de-coupling of power rails for example, in X7R guise. More demanding locations usually feature C0G version.
Awesome, thanks! I've just bought a few more meters
Thank you for the lesson! I truly enjoyed it.
brilliant explanations about capacitors :)
Great video ❤. Thanks for so detailed explanation 👏
Thank you, 😊 I didn't know that discharging a cap with a screw driver was a bad idea 😬 I'm definitely going to use the tip you showed here anymore 😉.. Nice one mate. I Always say if you don't learn something new every day then that day was a waste of time 😉 so thank for that.
I’ve got more than 100 mainboards in my “to re-cap” pile…I guess there’s no excuse to not be getting on with it now 😆
Edit: Fu*king hell Richard, you’ve got almost 5000 subscribers already, your channel is flying!
I've only got one mobo to do but not sure if it's worth it as it's been obsolete for a long time.
Probably a good idea if only to practice my de-soldering/soldering
@@1crazypj The more time that passes since it became “obsolete” the more worthwhile it would be!
@@jonchapman6821 True, I have a bunch of games that will play on it as well.
My 6yr old grandson has been looking at some 'driving' games and I still have the Microsoft wheel and pedals that haven't been used in ? years (20+)
Verry informative material 👍 Great samples. Thank you.
25:25 - This meter injects a 100k signal into the circuit to be measured. Have you ever come across a circuit that was potentially damaged by this (e.g., microprocessor chip)?
Not sure if I missed IT, but another good thing about an ESR meter is you can check a capacitor that is still in circuit
Very nice video and really complete. Thanks for sharing.
@LearnElectronicsRepair,I'm just learning electronic circuits, but if you could help me by explaining if capacitors block dc and allow ac,why does the large capacitors come after the bridge rectifier in the switch mode power supplys,hasn't the ac signal already became dc at that point,and if so how is the dc being accepted by that large capacitor to be used afterwards?
Outstanding teacher!
EXCELLENT I learned a lot. Thank You
This is the channel I wish I found long ago
Hello, thank you for your UA-cam video.
I am wondering if capacitors can charge before fully having discharged.
Does AC blocks discharging or does it add to the voltage of a discharging capacitor ?
Thank you in advance.
Hi could you do a beginners video on what a short circuit is (For dummies) Also do you do phone repairs maybe doing some videos on iphone chips capacitors/resistors might be beneficial as well
Paint a black dot on all … facing the front of the machine…
And Photograph.
Always useful.
hello, how do you know which is a decoupling capacitor and and witch is a timing capacitor looking at that GPU? It is a jungle there ...
At 2 minutes you drew a symbol calling it a polarized electrolytic capacitor. I was taught that it was a non polarized electrostatic capacitor, but the curved side was there to indicate the outer side of the capacitor’s foil. This was to simply be placed towards the chassis or any ground traces. That way if any accidental physical shorts there would not be as big of calamity
Hey! Ok, I think this is because I am new… like very new to this, but can you explain what you mean by noise between 11:00-12:30. Im having a rough time understanding this
Thank you for such an extensive and very useful explanation, I thought I knew everything about capacitors and here a pleasant surprise, I am gaining a lot of very useful knowledge, thank you again for taking the time to explain how it all works ps. Could you ever make a series on how to read schematics and explain how some circuits work? I know that this is a topic of a river, but maybe someday you will find time to talk about it at least a bit, thank you Łukasz, greetings from Poland, sorry for my English🙏🙏👋👋👋👋
There was also an era in the late 90's to early 2000's, where electrolytic surface mount caps were bad. These were predominantly used in video cameras, and had poor quality base rubbers, that leaked very early in their life. initially very hard to detect as damage and spillage was under caps (tracks eaten away). Whenever you come across any electrolytics that leak from the base, be sure to thoroughly clean and neutralize the electrolyte, especially on multi layer pcb's. Many of those repairs we did, involved tracing and re linking eaten away tracks in the camera's, which is very tedious and time consuming work. Ex technician, some 18 years domestic electronics thru to industrial comms engineering companies.
The electrolyte is absolutely not the dielectric in an electrolytic capacitor. The aluminum or tantalum oxide is the dielectric, the electrolyte acts as one of the plates, with the metal film or powder being the other plate.
Thanks for this great video! I'm learning lots of new stuff from you :)
I have a question.. I am always tinkering with old motherboards and video card. Just about all of them have the aluminum electrolytic Capacitors. How do determine which solid to use in place of the aluminum electrolytic Capacitors?
Hi Richard, I have been binge watching your vids and love your teaching style. I'm trying to educate myself on electronics repair and had an idea for a project, would love your thoughts. I would like to make a basic tool to read the voltage across a capacitor and drain drain it on command. My understanding so far is that different resistors are appropriate for different voltages so I wondered if it would be possible to apply the correct resistance intelligently in some way either with a microcontroller of some sort or with clever circuit design.
Would love any feedback and please feel free to come up with something yourself that newbies like me could all learn from, might be an interesting video. My assumption is that this tool does not have much in the way of demand otherwise I'm sure my google searches would have come up with something.
Which is positive and which is neg for an electrolytic capacitor, the shaded side or the clear side, there is no plus or minus on the board, thanks
When replacing electrolytics, the + - markings on the board can be wrong. So always note the actual orientation.
20:06 but you were touching the capacitor’s leads when measuring capacitance. Doesn’t that influence the value?
Another great video. Thanks for doing these
Hello Sir and thank you so much for those very clear and live explanations you give us for free! I have a subquestion to ask you, sorry if it sounds obvious. Because I'm french, I think I missundestood what you said at around 38:15. Are the eletrolytics the ONLY ones that I can test with the ESR or are all condensators usable with this tool ? (is it ok with Ceramics, tental...) - Thanks a lot for you answer and once again for your pedagogy! Alex (sorry about my poor english)
I can't seem to find that resistor he used to discharge capacitors - any recommendations?
Great video 👌🏻👍🏻
Thanks for this video, I understood the first one of the series on reistors a lot more, found this too much to take in and got very confused. Not really sure about a lot of what was talked about, but i'm going to keep watching and probably watch this one again at a later date.
Thanks for the video .
Could you use a darker pen for the diagrams as blue doesn't quite show as well.
@32:45 does this mean that you drew 4 anodes and 3 kathodes = inequal pairs? I tried to look structural pictures from google but they're way beyond my 2-year 90's electrician school understanding.
I would like to know if I need a capacitor type, ohm and capacitance for a cb radio on my school bus the radio loses power when the yellow light button is pressed thank you for your time
Another great video. You're really helping me to bolster my basic understanding of electronic.
May I ask, are you originally from the town I grew up is, Stoke on Trent? Your accent sounds so familiar.
You could use an analog test meter to discharge a capacitor too.
The problem that I have with learning stuff like this is that its SO MUCH information and I have absolutely no internal base to put it or attach it to anything else I know. It's just a bunch of words with no associations.
Great series... I'm enjoying and learning much from them as I work my way through them all.
With the ESR meter, what are your thoughts on one of the multi-testers like an Aideepen T7 TC-T7-H (transistor, diode, capacitor ESR, etc.)? Is it good enough for a general hobbyist or do you think a dedicated ESR like the MESR-100 is worth the buy? Trying to spend my money in the right places and if a multi-tester works, then it is always preferred for me at least. Tx!
Can we measure ESR with ESR meter in circuit (PCB) ? Thanks!
Not really, you need to take the capacitors out to measure the ESR effectively. Often the faulty capacitors are visibly bad but they can look perfectly OK and still have very bad ESR so the circuit will not work properly or even work at all. This is where the ESR meter is so valuable, otherwise the only other way to find those faulty capacitor is by substitution
You can use the ESR meter for finding short circuit MOSFETs in VRMs, and also to measure the value of inductors. I've shown the ESR meter used to trace short circuits in several videos
Excellent, thanks
ESR reading runs a frequency to test. DMM can't do that. R reading on leaky cap will slowly increase. Common with electrolytic cap.
I found a regular meter works good on testing if the capacitor is good or bad by see if the capacitor charges and discharges by switching the leads both ways if it doesn't its bad even if the capacitor reads the right capacity it needs to pass this test thanks
I love these videos!
i clicked LIKE, the subscribe and the bell - i want to support knowlage! thanks for doing this video!
Great channel love it!!