Board Repair Basics #11 - Finding replacement components 

For a small resistor that has no marking and you have no schematic you could try searching for the IC next to it. Chances are that you'll find a datasheet of the IC with a general purpose schematic and you could find a value for your resistor from there. I got lucky this way one time so it's worth a try :)

Hi There...Thanks so much for all of the time and knowledge that you are willing to share with everyone here! For me, your "Board Repair Basics" sessions are the best!! You using the boards/boardviews and schematics to explain everything in such detail and going back and forth between them telling us how they all work together and breaking things down to the most basic level is what I have learned from the most!! Always looking forward to your next post especially on your Board Repair Basics series. As you gain more popularity and notoriety I hope you are able to still consistently post new videos. I can't even imagine how much time and effort that must go in to having and maintaining all the different RU-vid DYIers websites. Thanks to your family and friends who have I am sure felt some impact of the sacrifice of time you must make to do all of this! Keep up the great work and I am sure everyone else here as well really do appreciate the time and effort you invest!! Stay healthy.....Thanks Again and Regards

As a kid, I tried to fix my N64 by replacing one random capacitor of the power brick, so I took one of the same size and close enough voltage (if I remember correctly) off a old radio, completetly ignoring the capacitance. The thing blew up as soon as I plugged the power cord, I was shoked. That day, I learned something xD

You're always underselling your repair skills. Wish I knew someone like you in my neck of the woods (Western Australia). The computer guys I've come across so far in my area wouldn't have a clue about half the stuff you go over on your LFC and BRB videos. Doesn't stop them charging like a wounded bull either (equivalent of over 100 quid/hr) for techs who look like they are barely out of grade school. So I just hope your customers realise how lucky they are to have you as their IT Mr Fixit!

All your vids are an informational treasure.4 years in university I never actually leart anything there. You should show uniniversity teachers how to actually teach. Kudos to you, you provide so much value especially for free. You should open a patreon or a join button.

I'm new to board repairing and I just gotta say, your videos helped a lot. you explain everything very clearly. Thank you so darn much. Finished with the basics now gonna watch LFC. Keep up the good work!

Just wanted to express my thanks for this series. I'm a beginner, and I felt like I got a *lot* of value out of it. Thanks, and best of luck with future videos and ventures!

Beautifully done. Rare to have the depth of detailed instruction, loved it learned more in one video from you than i have in a month from someone else. Great job! Thanks

I built my first pc in 1999 and just finished my most recent 3 months ago. I was trying to look back and figure how many that has been and can't quite figure the exact number, but several. I can troubleshoot hardware and software problems fairly well. What I can't do is the mainboard repairs that you have done in your videos. It's been quite a learning experience to watch. Valuable as well. Keep up the content. It's great.

Brilliant. You explanations are excellent. You are filling all the little gaps left off by Rossmann that made me not quite understand what he was doing. Just brilliant. Thank you.

He FINALLY brought up the chair hahaha Thank you for your great information again. Learnt a lot in a week watching your video's and still going through all the oldies but goldies. Thanks again!

Dude, I seriously LOVE your channel! You have taught be so many little things on fixing motherboards that all I need to do now is, well...fix a motherboard!!! ;) Thanks!

Thank you for sharing your valuable knowledge and experience. Thank you for explaining the subject matter in detail. I very much enjoy watching and learning from your videos.

Amazing series, very clear, thorough and easy to understand. I cannot express that better.

Adam Ant, I like it. Very good information for an automotive ASE Master Tech fixing everything. My first experience was the sound quit on our console TV in 1984. These where the ones that took two men and a boy to move. While we borrowed another small TV, I placed it in a room away from four kids, took the back off, started at the transformers secondary. This is when I learn of 5-6 voltages required to operate different parts. When cold, it worked fine, warm things heated up. But one evening, the TV in that room went silent. I unlocked the door and took my DMM, and started to check voltage while hot and current. I found one spot with 12 volts that had a wire the went to the other side. Flipped the board over and found a cold soldered joint. Re-soldered it, tested and placed it back is service in the family room for all six to enjoy. I learned, never new about multiple secondary's on a transformer and was the family hero. Neighbor girl dropped her portable radio a few weeks later. I found the PC board cracked on the transformer end. A heavy part on a thin board. I epoxied the board in place, scarped the coating off the circuits and soldered jumper wires across the fracture. It work for years before we moved. Still my wife is friends with the sister, but remembered the repair. Thanks for sharing your skills, insight and experience. It's part of learning still for me. It does seem cruel somehow, the older we get, the smaller the parts are. I have Motorola IC's that have no data sheets on. Thousands of them in 8 cabinets from my grandfather. They stay with me. Blessings.

Your videos are awesome, iv been fixing computers for years, and our processes are very similar...iv just watched your MBR recovery video. that was cool. I was always going the long way round.. saving all the files. And doing a re install. So thanks for that 👍😊👍

Appreciate you sharing the knowledge in the way you do. You call yourself an amateur which is a great sign of your humble personality. Yes I've seen Rossman, Northridge Fix, Electronics repair school etc but the smallish size of the videos and 'to the point' explanation style works for my A.D.D mind great. I just subscribed.

You’re no dunce. I started off my career, after my oldest son was born when I was barely 17 years old, in electronics. I did some temp jobs before I took a job in a repair shop. Similar situation, we fixed everything, no schematics. Everything you’re doing is right in line with how this is done at the professional level, including having tons of boards for getting parts from, buying common values, using heat to find problems etc. I later took a job as a Failure Analysis tech for a power supply company called Datel, long since bought out by another company. In that job, the task was never to repair the DUT, but rather to determine exactly what caused it to fail in the first place, and to describe the failure in total detail. In that scenario, we had the benefit of all schematics and the complete history of other known failures of the same device. I moved on in my career and took a job with Bose for 18 years working in other areas of technology, most recently software development. Looking back - I’m now 48, kids are grown and my wife and I keep chickens... - if I resume working in ANY technical job, it will be repair. It was always the most rewarding feeling to bring a dead device back to life. I HIGHLY encourage more young people to learn to repair things. It’s good for the soul. Keep up the great work! Subbed.

I didn’t sleep last night because of your videos but I’m so glad that i learned many things 🥰

I am in the process of setting up a lab to do microcircuit repairs and find your videos to be excellent; even the seemingly overly long ones have great value to me. Even though I travelled the world working on computer/electronic systems long ago, the basic electronics theory has not changed but the use of microcircuits has made things more "interesting". Thanks for your videos and keep them coming.

Just came across your channel, and that chair comment got my sub. Thanks for taking the time to make these. Looking forward to learning from your experience!

24:30 The larger cap that you soldered on the left has a whisker of solder almost touching the capacitor next to it. That shouldn't cause any issues since both capacitors are connected to the same traces, but newbies should watch out for that. Fresh solder with flux will want to pool on properly heated, tinned surfaces like your soldering iron, or the silver (or untinned copper) pads on your circuit board. In this case, the tip of his iron is a knife tip and he is only making good contact with the side of the capacitor. The copper trace beneath the capacitor is not getting enough heat from the tip so it is pulling the heat out of his solder. As he pulls his iron away the solder starts to harden and stretch like silly putty, causing that whisker. The fix is to switch to a chisel or a bevel tip. They will let you make contact with the board and the side of that capacitor simultaneously so they both get the right amount of heat. Also make sure the iron is in contact with the board long enough for the pad to get up to temperature. If the solder still stretches like putty, it may be bad solder or not enough flux, so experimentation is in order.

I have assortments of everything imaginable. In both through hole and SMD. I started out with only about $100 worth of assortment. And it proved to be so useful and it made my life so much easier… That I now have probably $300 tied up in assortments. But RARELY do I have to order apart. Everything is at arms reach. I have everything from the common stuff like resistors and caps, I must have 10 different types of capacitors. From standard electrolytic, ceramics, multi layer, film, high voltage, tantalum, even weird stuff like X and Y safety caps and stuff like that. Anything that could fail and need repair, or that I might use in a new build. I even have weirder assortments like commonly use Peltier coolers, photo diode’s, SMD to dip chip conversion PCB breakout boards, common sizes of plastic battery holders for AA AAA and 9 V… Even 18650. I have SND and through holloway chip assortments, and I’ll kinds of meat and weird things cost me pennies on the dollar and I’ll save my ass countless times. I definitely suggest component assortments. I’ve done in-depth testing on hundreds of individual parts from these cheaper Chinese component assortments… And 90% of them tested very well even under stress. But stick with brand-name high-quality components when using electrolytic capacitors. I’m lucky to have nice (somewhat older) equipment for evaluating and stress testing components both SMD and through hole. I’ve been very impressed with the component assortment and the individual parts quality. I have an entire large filing cabinet drawer with about 50 pounds of through hole parts assortments. Most of which were purchased ready-made from reliable Chinese sellers. Which come in individual plastic box organizers with component label mapped out on the top of the box to easily find the part. I can’t tell you how invaluable this is for keeping an electronica lab, whether you do repair, or new builds. Hardly ever do I have to order components when doing industrial electronics repair. Everything is at an arms reach. I’ve got dozens of assortments in both through hole and SMD. One thing in particular I’ll say… I stock four sizes of SMD components. Mainly because I’m doing repairs on industrial equipment and wanted to have many sizes at my disposal. I stocked the most common used sizes. Instead of purchasing resistors and capacitors separate for each SMD size, I found several eBay sellers offering “books“ containing both resistors and capacitors of a given size. And they are enclosed in a nice little booklet that has plastic pages which perfectly organizes and labels the components and values. In particular for example my book of those 603 resistors and capacitors contains 175 different values of resistors and 55 different values of capacitors. The book was around $30 delivered and I have onefor all sizes of SMD components are commonly worked with. They also sell the “SMD books“ completely empty....so that you can fill them up with your own components. SOOOOO...I put together a custom book of SMD semi conductors ranging from transistors, rectifiers, switching, Schottky, pretty much any SMD semiconductor you could ever imagine from the most common to the most obscure. ranging several different sizes. This book cost me a bit over $100 to put together. but hell I’ll save that $100 in shipping alone after using only 10 or 15 parts out of the book! Considering digit key or someone would charge me five to $10 to ship a single component. My SMD semiconductor book contains close to 20,000 pieces. All organized in sections and part numbers. . Thousands upon thousands in several different sizes. And I can’t forget my wonderful and beautiful assortment of LEDs from the tiniest surface mount in every color… Up to my massive driverless cob chips. Sorry to ramble on… But this is some thing that has saved my butt so many times and really does come in handy when you have it. Whether you spend $50 on assortments, $150, or several hundred dollars… You won’t be sorry!

It would be cool to see a Q&A. It would be cool to learn about your shop and how it all started! I've learnt a lot about repairing PCs from this channel. Thanks!

Thanks sir for this videos, It’s realy helpfull for a Newbie like me. I’ve already watch basic repair of your’s from #0-#11. I hope you continue what you’re doin. God bless andtay healthy.

your videos are a life saver!!. I had knocked off some tiny caps and resistors from my xbox one s board while repasting the thermal compound. Now I can hopefully fix it!! The boards says the cap is C1p11 but without schematics there was no way to know until now.

"The size of the component doesn't matter". I'd beg to differ. The size of the device has great influence over the device's parasitics. A physically smaller SMD capacitor will work better at higher frequencies then a physically larger one of the same capacitance, because the smaller one has less parasitic inductance. (not that it would matter in this particular instance). Also note that some of those capacitors around a buck regulator are critical. For example, on this board PC60 and PC144 (close to those 2R2 resistors) are the bootstrap capacitors that act as a floating gate supply for the top MOSFETS. If those were to break they have to be replaced, the top MOSFETs can't switch on without them.

Lovely video again ty. always good to share knowledge and teach others a trade that can put food on the table. keep up the good work buddy and stay safe and healthy.

Big thanks for your work again from Germany. Keep it up

This is such an underrated channel!

I came across your video's about 2 weeks ago when I was hating my pc because it was not booting, after watching a few video's of you and the time and rest that you have I pulled thru and fixed my pc. (apparently every time I plugg my RX 580 8gb my M.2 ssd doesnt work... I have 2 b450 boards and they both do the same) Thanks for the vids😊

I watch the High-Dollar people (NorthridgeFix/NorCal715/Mr. Carlson , etc.) do this , but I am amazed by Adam Ant's abilities with the limited equipment he has.

I love all your video!! Very underrated channel

I love your videos because they are so informative and helpfull! I'm really learning alot from watching.

Before watching your videos I was never interested in board repair but now I look forward to watching them, don't ask me why, well you do a nice job in breaking it down to help us process the information. Get it? I said process? It's my bad computer joke. :)

Man great video, I am learning a lot. Just bought my packs of capacitors and resistors.

Great information! I like it. Thanks for sharing. "Pro tip, quit while you're ahead." 🤣🤣🤣

Great explanation on switch mode power supply!

Another great video, well done, Thanks!

Nice and very helpful explanation. Thanks a lot bro for your time and effort to support another human being. 👍

Yet another informative video 👍

keep up the good work, i am so enjoying your channel.

Very informative thank you. If you lightly grease the pins and contact points of your chair you'll get a few more years out of it. I've done this with a 500.00 gaming chair that started getting noisy and worked perfect.

Caps are often used to filter noise from the DC lines, if you have a long trace acts like a coil and picks up spurious from other components. Also each line have in serial ferrite to block high frequencies generated from active components like CPU, mem , etc

Excellent video. Thank you so much!

As a rule of thumb, stick to X7R mlcc caps around switching circuits, it's advisable as they are more stable around heat. They are usually rated for 25v or 50v

Very helpful & well-explained 👌👏

You tried your level best to explain about capacitors. With due respect sir while at the time of your speech 2R2 you have told 2.2k ohm it should be 2.2 ohm.sir plz correct it. thanks for nice video.

Great explanations.

Excellent video for beginners, thanks

thanks for this series...

Thank you so much!!!! Great video 👍

love you teachings bro

Thankfully, working in a School we tend to buy multiples of the same make/model laptops and as the staff/pupils keep coming up with new and ingenious ways of breaking them, the chances of us having a 'spares and repairs' laptop is quite high! So as long as it's a different issue we can use another board to identify components.

Thanks for the quick reply.

thank you so much for your nice very comprehensive repair lesson I hope you will do more bye

Thank you so much for explaining this. I love troubleshooting, but there are not enough videos explaining component identification. Everyone just says "I have a donor board"

Very informative video!!!

So so helpful. Thanks.

To calibrate your component tester on those models you usually just short pins 1, 2 and 3 on the DUT socket and power it on. For the resistor code that was (I think) 85C it is an EIA-96 code, so you need to look it up (on a EIA-96 chart) or use an online calculator. 85C = 75K. Hope that helps. Keep up the great videos.

New Subscriber here thank you for a lot of lesson ive learn to you sir..God Bless..

this video came on time 👌👍👍 thanks

This video makes me subscribe your channel. Very informative. Thanks

Yeah 100nF is a very common value in electronics, it's a bypass capacitor to remove the fast switching spikes when ICs switch signals. Usually 1x 100nF per IC. I design and build electronics, so I have a roll of 1000 of these caps.

I just love those ceramic tipped tweezers

Hotwire tweezers work real good with these components

Thanks for the video. By the way, you don't have to replace the chair. Just some drops of oil on the skeaking area will do the trick !

Thanks to your I'm starting to do SMD repairs, I like the way you explain thing and make simple to understand I have two laptop I working on one wont even post and has no display on the screen, so I not sure if it's posting or not.

Very informative video.

great lesson thank you

you explained a lot.🙂 thank you

As a teen, I was repairing a TV using flat screwdriver. I touched a capacitor, uh oh- melted the tip of the screwdriver and it also threw me across the room. The days of home TV repair ended that day for me.

Thank you for creating extremely helpful and informative content. Do you have any tips for finding issues with fan headers with no power on a gpu?

Love the tweezer

Excellent 🖤

i am French and i dont speack english but with the translation i understand ^^ thx I finally understand the usefulness of capacitors :p If we had to test with an osciloscope we would see its curve change? (with and without capacitors) super channel I really like your explanations ! ;)

Caps can be measured in circuit using a M ESR 100 meter. Hope this helps. 🤓

Spray some WD40 on the squeaky parts of your chair. I did it with my chair, worked a treat.

Thank you for nice explanation

Not to mention that you can recover the cost of the bumper pack in the very first repair you use it for. Nice.

Great video thanks, what soldering iron and heat gun are you using? and whats the typical temperature they are set at for these jobs?

Thanks alot am learning

Well, resistors and capacitors are easy. Finding replacements for CHIPS is the real deal :q

Excellent diagnostic video, enjoyed watching you go thro the steps. I have a 27 2011 Imac thats refusing to boot any ideas ? Gone thro ram checks, battery removal & replace, swapping power supply, no power to the board or fans. I suspect the power button. No beeps at all?

wow outstanding technique thank q so much for u r provide such pretty knowledge

You can oil the chair... if you find the right dang area to oil. It sounds easier than it is though; sometimes the fault can be inside some "black box" of magic reclining machinery. Other times, like when it's just a stool, it's much easier to find the correct area... or to just drown the thing in oil. :D

Very interesting video thanks buddy, I'm a vehicle master technician and want to learn more about the ecu internals and eventually learn how to repair them - any tips or videos you can recommend?

Very educational video , let me suggest. U to write book Side by side when u have mood,as u have good command on language Very much appreciate u r honesty re repairing , trough out our life we r learning No one knows every thing Any way Tks for helpful videos&(multi packs)

Fascinating video; great to learn the role capacitors play explained on itself effects on a waveform, in plain yet accurate English. Just one question, where was you during the electrical engineering module in my CS degree? 😂

Using thermal camera to see hot spots would make your voltage injection TSing faster and look cooler on your stream!!

What's seems to be missing from this series is more diagnosing if the protection circuit has sensed a failure and telling the control IC not to boot, ie, a totally dead MB. Basically you can't find any shorts, so what do you do next. I think the control IC senses voltage, but it's too hard to trace the many branches with only a boardview. So the only way I can think of to check that is supply power and hope nothing fries. I think it also checks current, but what else does it look for.

Thankyou very much sir

good choice of soldering iron ...

I enjoyed this video and learned a thing, or two. I suggest that you start to transition away from Ebay/Amazon/Etc., for buying parts. There is a high probability of getting poor quality/fake parts from them. Use a proper electronics retailer, like Mouser, Digikey/Etc. They sell assortment packs, as well. Their quality is worth the price difference. I did as you, using Ebay to start. But, when I ran into a poorly made component, it greatly complicated the diagnoses process. HTH

Great mobo foundation Video. Question while talking about changing and sourcing components would not replacing even a sub-critical component within the the cpu / v-core power rail not impact on the performance, and can this be seen (tested) through software diagnostic and test programs? I have an issue with a GPU i repaired it. and it worked great but the GPU diagnostics / and over-clocking utility showed issues (it would not longer over-clock- and vcore was all over the place). It would be great if you could show a working board and any post repair diagnostics.

I usually just use heat proof tweezers to get the SMD components in place and hold them down when I'm using hot air!! Otherwise they go everywhere😂

32:05 That resistor is written in EIA-96 format and 85C = 75kOhm

That's a Dell Inspiron 1501 and it's a Quanta FX2 board schematics are easy to get. Some where on the mobo will be a number like this "DA0FX2MBAD7"

I had a look on eBay for "sample kits," and I found a bunch of books with pages full of capacitors / resistors. Are these any good for this purpose?

what type of pcb camera are you using?