Repairing a motherboard with a subtle intermittent fault

[@tarnaigy]

1:15 "People are gonna be disappointed, because I will not continue... Let me just try one more thing..." - and the video goes on for almost 2 more hours... only on ADB... :D:D:D

[@tarajoe07]

And we're in fact happy

[@tarnaigy]

@tarajoe07 So say we all.

[@kilroy79763]

indeed and so glad he did

[@meh78336]

If someone told me they had a SCAT motherboard, I would assume they were being polite about saying it wasn't very good :D

[@ToxicwasteProductions]

I wore hoping for some jokes about the name 😂

[@mariestarlight]

Reminds me of VMWare Esuxi (yes I added the u)

[@TheVdub1980]

Scat = Poo where I'm from or Poop in USA lol

[@moloch5801]

RIP Scatman John

[@KorAllRBare]

🤣😂😅

[@jacobcoffey6511]

Absolutely love the long form video. I feel like you actually got to cover all the little nuances and we felt a better understanding of the board in full. Thanks for all you do!

[@integerofdoom69]

Long form is king!

[@kilroy79763]

Adrian, I love the long videos...ill work at my desk (im a college professor teaching electronics and computer science) and listen and look now and then to your EXCELLLENT workk. Thank you for your inspiration and knowledge...I have learned so much in my life and forgotten so much. Your channels is a great place to remember and learn new things.

[@dparks256]

Agreed, Adrian narrates so well you can follow along even if you have to look away.

[@ka4hre]

long time viewer / listener to Adrian. I'm an electrical engineer from 1985. I find it a nice escape to listen to him and listen to how he thinks. his curiosity and enthusiasm is infectious.

[@kilroy79763]

@@ka4hre Agreed !!! He is one of the few people that I patreon

[@cls9474]

Thanks! Surfin' w/ adblock but without YT-Premium. This should compensate it for a while. All the best from the Swiss mountains!

[@TomFynn]

"Now I'm going to use a brush, really trying to get in there" Massive Bob Ross flashback.

[@michaelturner2806]

"I'm just going to finish up and not troubleshoot this any more." *two hours of on screen edited-down troubleshooting* Adrian, you're so thorough! I love these long form videos. Only thought is maybe this could've been split into two or three if you wanted to, of that would please The Algorithm.

[@nysaea]

ngl that amused me to no end too xD

[@MikeSmith-sh3ko]

I would would have chucked it out the window by now Adrian . But you learnt a lot from this repair thanks for sharing it with us 👍

[@volvo09]

I'd just say screw the CMOS battery! What a crazy hunt, I would have lost my mind! Haha

[@ishmobile]

Thank you for sticking with it and figuring it out. You do such a thorough job fixing things and inspire me.

[@quakesin1982]

This is the best kitchen cleaning video I've ever seen!

[@ElijahWoodward-e5o]

The long form videos really help keep me company on my more insomnia-ridden nights and this one in particular was a really fun ride. Stupid capacitor! I’d watch a livestream too!

[@chasonlapointe]

What a marathon of a video, keep up the fantastic work!

[@mikegravgaard340]

I love long diagnostic videos. It is good to see and follow you through a diagnostic process narrowing down the problem to a working fix. Interesting Nacroware had a very similar issue to you on an EISA motherboard and his fix was to fit a second CR032 to his battery holder using the four pin header on the motherboard (he removed the CR2032 holder which he had fitted after realising this needed to run at a minimum voltage level). I would suggest watching his video as you both had the same issue.

[@quadmods]

I’ve worked in tech support for decades, “subtle intermittent fault” is a truly horrifying statement… 😂

[@jeromethiel4323]

I hate intermittent faults sooooo much. Because i am a FSE, so my time on site is usually very limited. My ability to actually find an intermittent fault is basically zero. What i usually have to tell a customer with one, that they either need to change the entire thing out, or to wait till the intermittent issue becomes frequent enough to actually find.

[@moosemaimer]

At $lastjob we had a customer whose VOIP phone would act up at the same time every day. Worked perfectly the rest of the time, and no indication whatsoever in the datastream that anything was causing it. That lot of phones was recalled by the manufacturer due to a fault in the LCD screen causing a photoelectric effect, so when the sun came through the window and hit that person's phone, it turned the display into a solar panel and sent voltage in new and interesting directions.

[@TheRaker1000]

I personally would never spend that kind of time on a 386. I'm thrilled that you did so I could watch this video. When you got to the point of finding the errant capacitor it was very satisfying. Well done.

[@JohnGotts]

Spoiler alert! Leaky cap makes sense.

[@insanelydigitalvids]

Really enjoyed the long-form video. Having more of everything you do is icing on the cake!

[@kirusyaga]

Finally, some good long video. I was watching this video in several approaches because of work. At the morning before the work, on lunch break and in the evening.

[@tony359]

I’m biased because I do that, but I don’t mind an advert or two in a long video. Things cannot be 100% free and a few seconds of my time won’t be a problem. Thanks for the nice video, amazing find that cap!

[@peregrine1970]

Can't speak for others but I really enjoyed the deeper dive in to the process.

[@saturn5tony]

The best troubleshooting i have ever seen, and i have been into repair a very very long time as well! Superb Adrian! Your love of retro is so appreciated 😊

[@jkeelsnc]

I enjoyed this long form video. Please do more. I learn something each time.

[@ProfessorMAG]

Amazing, nearly 3 hours and you had my attention the whole time! I too have spent DAYS chasing electrical gremlins like this. Imagine how impossible it would be to charge an hourly rate to fix this issue. I'm the kind of person who refuses to be beat by a machine and will not give up unless repair is proven unfeasible. I just couldn't justify my time to a customer (if I was still working...yes I am retired) Nowdays I just do this for a challenge.

[@vlerherg69]

I absolutely LOVE the long-form video and really enjoy watching you work through problems, use logic to try to figure out the mysteries and enjoy the eventual success along with you. Keep it up!!!

[@WY.C64-Guy]

The thumbnail says "I almost gave up...", and then I see the duration is nearly *3 HOURS*... .. This has got to be good. 😊

[@frankgroening9139]

really love this kind of videos. long and educational to the top!

[@GYTCommnts]

I hope these longer videos are popular and profitable for you. I love them.

[@PatrickFinnegan]

Adrian, you totally need to live stream one of these. You'd be surprised at how many people would watch i bet!

[@MarianoLu]

Those first 11:44 minutes is exactly why I watch this channel. Great job Adrian on the main and second channel videos keep it up

[@NeiroAtOpelCC]

I don't know why, but I enjoy the videos where you're struggling more than the ones where you're just sharing your vast knowledge

[@KaldekBoch]

I loved this video - especially I love it when the datasheets come out and it's possible to deduce the root problem.

[@burn0u71]

a 3 hour long video from adrian? is this christmas in january? :) absolutely love your longer videos. i usually learn a ton from you cause you are such a great teacher. i'd watch 8 hour videos if you ever put some out.

[@ASMRPoohbear]

Wonderful video. I love the fact you show your fault finding rather than skip parts or fast forward. Also your videos are slightly ASMR like.

[@danhorton6182]

I would have to agree with most here, make 3 hour videos a regular thing! Really enjoyed this video, excellent sleuthing!

[@alexmirica]

Adrian, I love the longer video!!! Especially because the quality isn't decreased at all, it's just better! I love your rational thinking during troubleshooting, it's top notch!

[@zeckenhenker88]

Hi Adrian! I absolutely love the long Videos! You make a very good job. I am an 80‘s kid and love these old Hardware. Greetings from Germany!!!😊👍

[@EdwinNoorlander]

I like this format. Really like the in dept video’s

[@einsteinx2]

Love the long form videos! When you said you thought you were going to stop then I saw there was still like 2 hours left I got excited!

[@turtleschmiechen6155]

Great video, loved the deep dive. You must have a really clean kitchen now.

[@KarlDavies-dn3eg]

Ahh a long one!! Yes Adrian, something I can get behind, a long format video once in a blue moon, it breaks the week up nicely as I can watch bit by bit. As always keep up the the good work and inspiring us all.

[@Agent24Electronics]

Great video! It turned out to be what I expected, but not in the way I expected it!

[@copperminekd]

I would looooove to watch a 5 hour live stream of you repairing a motherboard! Even though our time zones are way off.

[@Adrian_Finn]

I do love these long edited videos, I personally find live streams difficult to sit through as they don't flow as well but I understand there are people that don't mind them. Wonderful content as always Adrian, had my attention the whole way.

[@kyorin6526]

It took me until today to watch the entire video (a week), looking forward to the new one tonight now 🙂👍

[@bouffman88]

I love your Tenacity as always Adrian, you got there in the end!

[@steves9753]

What great content, really enjoy all your fault finding techniques. I think the 6v battery on the schematics you were looking at was a clue. Wish all your repair vids were this long. Maybe a 3 hour long C64 repair-athon :)

[@Luke-rr9po]

Thank you Adrian, excellent video, I was certainly entertained for the whole almost 3 hours! 😊

[@Barabyk]

I guess there was a hint in the schematics shown 6V battery supply and in description of the circuit it mentioned 1.8V drop after 3 diodes.

[@kstricl]

You're taking away my excuses to begin salvaging the VIC-20's in my garage. Guess I'll be going back and watching the troubleshooting with a cheap oscilloscope video that brought me here originally. Not gonna lie, I watch these long form vids at night usually, so I did conk out a bit, but sooo satisfying to see you finally track the true fault down at the end.

[@josephficara3666]

Loved this one! Great work and thank you for sticking with it to the end and figuring it all out!

[@qwert777asdf]

Am I the only one who would enjoy a five hour video?...

[@erber-w6b]

One of your best videos Adrian, good job! Greetings from Québec!

[@mogwaay]

Loved this video, it must totally throw your production schedule out the window, and maybe some of your sanity 😂 but I REALLY appreciate your tenacity to get to the bottom off issues like this battery thing, I was hooked! Cheers!

[@AceStrife]

I think there should be both long and short form content to suit everyone's preferences. Sometimes you want to leave a multi-hour long video on in the background, sometimes you want to watch a quick ~20 minute video while you eat lunch, or anything inbetween. Those of us who have a lot more free time will trend towards the longer videos, and vice versa. Also don't burn yourself out trying to stay fit to a schedule. If you need more time to work on something, just take the time; you work for yourself now. Livestreams could be good for a casual evening, great opportunity for Q&A as well. Fitting in with "regular" content and also not cannibalizing it is where the balance lies with that though. Some creators start livestreaming then shift over to it as their main focus since it's so much easier to produce, even taking livestream footage to put into a previously 'normal' video. Either way, personally I'll watch pretty much anything uploaded to the channel (excluding food), so whatever form it takes doesn't really matter to me, but if I had to pick one (could do a few channel/patreon polls), I'd pick long form videos.

[@MatthewMcCoyathome]

first: I LIKE the long stream video. Second: my (not first thought) was a short in the system, but... third: a bad cap.... Little did I know that i was a short in a cap... Please, the long format was extremely enjoyable and entertaining. Keep it up.

[@horusfalcon]

Capacitor... yup. This was a bit long for me, but that's just me. You do good work. With the billable hours involved here, this repair would have been prohibitive for a paying customer, I think, but you saved this board. The new BIOS was just icing on the cake.

[@hugosimoes5119]

Glad you did this video. Probably someone in the past or someone in the future will stumble about this problem.

[@geiger9]

I love this long form video. Keep em coming!

[@jackdrizzleshizzle4389]

I love your "billion hour" video!! More of this please👍

[@greenmoose_]

I love the long videos! I doubt our timezones would align for me to catch a livestream but in principle that sounds great! One of the reasons I like KZbin Premium is that it does give back to creators a little bit more than ad revenue AND you dont have to sit thru ads! everybody wins 😂

[@solarbirdyz]

I watched this over a couple of days but I did watch all the way through it. ^_^

[@stamasd8500]

I have a similar 386SX system, it does not have the exact same SCAT chipset but uses the SCAPM instead which is the successor of the SCAT. Its backup battery is actually 2 batteries - it has an extra tall coin cell holder that takes 2 coin cells stacked on top of each other. I have always wondered why this particular motherboard needed 2 coin cells, but after watching this video I understand. The SCAMP likely has the same arrangement for low-power CMOS operation, and the 6V is needed so that the chipset sees reliably something between 3 and 4V even when the cells are partially depleted (which only 1 cell wouldn't reliably do). So even though my system is different, I understand its functioning better now after watching your video. Thanks!

[@trptmbalmer]

Absolutely epic troubleshooting video. Such a good deep dive into things. And as for livestreaming it -- DO IT. There are EE/retrocomputing people on Twitch who stream their stuff and I watch it all the time. Just go for it.

[@dparks256]

I have a new to me 386 DX 40 and a 486DX 66 board that just had their mildly leaky batteries clipped out, so this is a perfect primer video to have watched before cleaning and testing!

[@Tayken9127]

Love the longer videos Adrian, cheers!

[@DavidWatts]

loved it, thank you for keeping it so long.

[@myleft9397]

Holy 3 hours... haven't had time to watch it yet but I'm looking forward to it [edit: I'm still only halfway :D but my prediction is 4 x AAs would let the chipset chip power up, decide "oh no, I need to be in low power mode", and shutdown to ~1 mA, which means the AAs could last 1000-1500 hours? My first IBM-compatible PC was a 386, but it didn't use AAs for the clock battery, so I have no idea if this is plausible]

[@kjl3000]

Love the long videos, live would be very nice to see. Let’s do it! ❤

[@hiroshifox9020]

Really enjoyed this video. Was good to see you go through this to find a single capacitor being the problem.

[@cfjr9453]

Love the long videos, I watched this one is one go and loved it. For me it’s a win! Keep’em coming! Much better than binge watching s*itty shows on Netflix.

[@J0eBl0e]

I *loved* the longform edit for this troubleshooting endeavor.

[@DhaosEsedess]

love the long form videos and i would defiantly watch a live stream of you fixing stuff

[@lostngone2007]

No disrespect, I like the longer videos, but in this case, I fell asleep and woke back up and just thought KZbin had gone onto another one of your videos. 🤣

[@EricThacker-k3y]

Loved the long form video! Would love to see more of it on the second channel if you ever have the time.

[@andrewclegg9501]

Adrian, that was awesome. 3 hours flew by.

[@fhunter1test]

If I remember correctly multilayer capacitors actually tend to fail shorted. And also - they can be cracked relatively easily. Considering that it was near the removed battery - it could have been cracked by pressure, when the battery was removed?

[@jandjrandr]

I loved this long form video. Yes I watched the whole thing in one sitting. 🙃 While I can't say I would watch every video this long, the way you did this had me riveted. I felt like I was solving the problems along with you. Great work Adrian!

[@pr0engineer873]

Livestreaming would be good; You can use the power of the community to give you more ideas and point out things you might have missed. Plus being interactive is a really positive experience.

[@peterhubbard7665]

Excellent video Adrian. I really enjoyed all the testing you did and the logical process. I hate capaticitors.

[@JenniferinIllinois]

Woah, three hours of Adrian troubleshooting. This is gonna be good. Waiting for the “It freakin' works". 😉

[@kapitannemo7454]

Long videos are top! Especially when it is troubleshooting. Very nice work, so, have a nice rest)

[@gizmosx84]

I love long videos but not to talk about CMOS circuits, but it's nice to diagnose the circuits nice work

[@ChrisHarringtonMinneapolis]

Fantastic, this was great to have to listen to while I'm working.

[@pappakilo3965]

Great video in great detail. I'm not a semiconductor designer, but in both digital and power electronics modules at college we were warned against running silicon in its linear range if we wanted to keep power consumption low. Power switching designers go to great lengths to pass through the linear region very quickly because linear operation causes a lot more power to be dissipated and at megawatt levels that matters. Perhaps your chip also moves into its linear range when its supply voltage dips too low. But your faulty multilayer cap probably dwarfs that. A few bench experiments would be interesting to see what's going on

[@AnthonyRBlacker]

Whoa Adrian things got SUPER exciting 2 hours into this one.. I'm super grateful you recorded this entire thing.. I love it when you find neat things like this.. it's SO much fun!!!

[@patrickcraenen5163]

Hi Adrian, MLCC capacitors are notorious for failing with short circuits. I suspect there are also quite a few thermal effects when voltage is applied to the failed cap which causes the leakage resistance to fluctuate...

[@adriansdigitalbasement2]

Ah ok -- I couldn't recall their failure mode. It's definitely not something I work with a lot.

[@patrickcraenen5163]

@@adriansdigitalbasement2 Hey Adrian, I am certainly no expert and I do not work much with MLCC caps but I have watched quite a few repair videos of smartphones, laptops and other modern electronics :-) The short circuits would result from mechanical and/or thermomechanical stress causing cracks between the layers of the capacitor. I am a big fan of your channel, always super fun, funny interesting in depth content that everyone can definitely learn something from. Thanks and keep up the good work! Cheers!

[@gemedetvideo]

@@adriansdigitalbasement2 Yes, MLCC capacitors are known to short but usually only if they are exposed to some sort of stress. That can include mechanical stress, thermal stress, or even exposure to liquids. Otherwise they are quite reliable and don't tend to just short over time unlike tantalum caps. It is quite possible this particular capacitor was damaged by the battery leakage.

[@KatarinaMelki]

I have experienced an MLCC cap go short. It ended up going out in orange flame and destroyed the PCB.

[@gemedetvideo]

@@KatarinaMelki That's odd, there is nothing in most MLCC caps that would be flammable. They are made of layers of ceramics which is pretty much impossible to burn. Are you sure it wasn't a tantalum cap? Those are very flammable and do like to burst into flames when the conditions are correct.

[@scottzahorik5788]

I love the occasional king form videos! I love having them run while I'm at work. In my line of work i often have large gaps of idle time while i wait for large reports or system backups/ uploads/ or downloads to complete, and this video filled in the idle time beautifully. Thank you so much for what you do. I can't speak for everyone, but i find most of your videos fun and very interesting, and today it brought joy to what would have otherwise been a very mundane tedious day at the office. Keep of the great work, and I'll see you next time! 😉

[@eshwayri]

One of the best videos I've seen in a long time.

[@EarlTheSquirrel]

I very much enjoyed the long video! 😊

[@williamcameron1137]

This is my relaxion music. I mean that in a good way. Thank you.

[@Null_Experis]

Hakko still sells the filters. Hakko A5044 is the part number. They're $9 for 10 on Amazon. I have the previous model of desoldering gun and about 2 years ago they sent an email saying they were discontinuing parts for that one and to buy up stock while they have it. I stocked up on valve heads, tubing, a new waste chamber, 40 filters, a heating element and a replacement shroud for the entire tip. Should be enough for it to last another 10 years.

[@binkman853]

Loved this one. Long videos are great.

[@supernova6486]

I too love long form videos. 5hr video, no problem!

[@Kirill_Konovalov]

This was really good analysis. Very useful. Thank you!

[@bbjunkie]

Loving the long form video, hope to see more! 2:37:30 The slight time loss could be down to the crystal having aged. Over time they drift, this could be part of the time issue also.

[@achimboers]

I really appreciate the longer repair videos, they are more real compared to my own repair attempts and swing you go through the same frustrations and futile attempts to in the end figure it out is very inspiring. Thanks !!

[@wildcat189]

This video was agony for you but great for us! Enjoyed every minute.

[@ultrametric9317]

This was the Super Bowl of ADB II videos :) Great job.

[@John-jl3ky]

I like these long videos, good job!

[@HelgeMdS]

Definitely like this long video although I wasn’t able to view it in one session 🎉

[@croztech]

@Adrian I'm sure 1000's have said this already, but I love this long/unedited format. It tells the real story of fault finding, which sometimes is frustratingly difficult in complex systems. For reference, two standards (IEC 62380 and System Relibility Center) show the failure modes of ceramic capacitors as 90% and 49% short-circuit respectively, in both cases the most frequent failure mode. I guess we don't really think of ceramic capacitors going short circuit frequently, because their rate of failure (excluding mechanical damage like cracks or broken legs, if TH) is so low. Also, MLCCs can experience strange piezoelectric and non-linear characteristics with voltage, which might explain what you saw. Would be interesting to just put the bad part across a power supply and see how the current drawn varies with applied voltage (if you can find where you put it)... to summarize "sometimes good caps just go bad" 😉