Ask HN: How do I learn practical electronic repair?
68 juanse 58 5/31/2025, 6:14:47 AM
In my country, 2 decades ago there are were plenty of people who knew the basics. Today, it feels like a lost art.
I would like to approach it as a hobby, not like electronic engineer level, but enough to debug problem and change components to a low level.
What is the pragmatic approach in this mission? I reckon it will be valuable in the future that comes.
Anyways, I took pictures of the components and described what I was seeing. It walked me through things really well and asked me to do tests and report back. It even told me how to use my specific multimeter after I took a picture of it. I ended up soldering a jumper cable from the console power supply line (not working) to the micro usb power line (working).
It actually works now and really saved me 30 bucks buying a new controller.
I've learned not to fear B+, but to give very healthy respect to anything more than 500 volts. (Only use 1 hand, keep the other behind you, always have a safety partner, etc)
I've learned to hate Silver Mica capacitors. I've learned how to track down the bad ones that cause the "crashing" sound in old radios.
I've learned that in very old electronics, you can let smoke out, and things will still work. I've gotten good at seeing where the smoke comes from.
You'll definitely need to learn to solder. I'd suggest starting with something like an Arduino starter kit to get a sense of how components actually interact.
But remember, if something is dead, you can't really make it worse. (Just be careful not to make yourself worse along the way)
Man, I'd say be very respectful to anything that might be running 120-240V, and be very sure about anything higher than that. Anything <50V can often just be fun tinker whatever assuming you're ok with breaking whatever you're playing with, up to a certain max amperage of your power source. High amperage but low voltage can still cause some serious messups if you don't have the right fuses in place. But I get other voltages are common in Europe.
AC, 120V will 'bite', 240V will make you shaky (remembers id10t maneuver yesterday, first in a decade). And burn you. In damp environments or with corrosion around, much worse things can happen.
That said, even something as simple as surge protector power strip is going to have a nice and fast circuit breaker in it. If you want to get fancier, get a GFCI extension strip from home depot. And if you get an isolation transformer, it'll certainly have a fuse or a breaker.
Probably implied here, but learning to desolder is huge too. And there are tricks to it that didn't come easily to me. When you buy your first iron, I think it's worth getting some flux and solder wick as well. Taking circuits apart cleanly and properly can make repairs so much easier.
Apart from that, just fix broken stuff. Practice like any other skill, like others have said.
Like decide what skills to learn based on what’s broken.
Need to solder something together? Buy the soldering iron. Need to figure out which capacitor you need to replace with? Learn how to identify capacitors and navigate digikey.com
A cheap multimeter and a cheap soldering iron/hot air station combo will get you very far in the hobby. I enjoy these channels:
MyMateVince (a guy who fixes many useful household items): https://www.youtube.com/user/mymatevince
StezStixFix: https://www.youtube.com/@StezStixFix
Electronics Repair School (more advanced, he fixes laptops, tvs, and sometimes gpus): https://www.youtube.com/@electronicsrepairschool
When the problem is not exactly the same, I'm just lost. There is not a lot of diagnosis videos on YouTube. All the videos are: "1. I observed this problem. 2. [???] 3. I'll walk you through soldering on the new components." skipping the most important step 2.
Same for car repair videos: "I see Problem X happening. Problem X usually means component Y has failed. Here's how to replace component Y. The end." If that doesn't work, you wasted money on the part and your time ripping apart your car and putting it back together.
In the channels that I suggested, all of them go into the repair not knowing what the fault actually is. They take the viewer through the whole diagnosis, and they (with the exception of Electronics Repair School) are not electronics technicians.
Once a person has seen enough different ways of diagnosing items (by watching videos or hands on trying), then faults in other items become easier to find.
1. Take things apart, and try to figure out how they work. Don't worry too much about getting them back together. But then, trying to reassemble it is good practice too. There's plenty of old electronic junk that you can explore before throwing it away. Build a mental catalog of how things work and are assembled. Among other things, this will help you when you need to come up with a strategy for getting some particular gadget open -- often 9/10 of the problem.
2. Like others have said, YouTube is great. People will make a video of a repair, or even just getting something open, for a few "likes." Also, most of them are just normal genuine people who aren't trying to be influencers, so it's kind of culturally refreshing. Many of my successful repairs started with YouTube, such as my clothes washer and dryer, refrigerator, lawn mower.
3. Many of my most cherished tools are what I call for "demolition," not electronics specific, like picks, pry bars, a slim knife that can get between things, stuff like that. Another set of cherished tools are my magnifying visor, small magnifying glass, bright flashlight, and a stereo inspection microscope that I got second-hand.
4. A lot of "electronic" failures are actually mechanical in nature, and you can just use your general troubleshooting rundown to figure them out. Switches, connectors, cables, etc.
5. Begin to get the hang of identifying parts, and how part numbering schemes work. It will help you in your search for spares.
6. These days I often ask my spouse for a opinion. She's a laboratory scientist, quite sharp and skeptical. I'll have a hypothesis, and she asks the one question that blows it out of the water.
Good luck! Don't get electrocuted or burn your house down.
2.Soldering iron, for starting out I suggest spending a little more and getting a Hakko 888 instead of something cheaper.
3. Flux, Leaded solder, Braid.
4. Broken things you want to repair (for me it has been electronic musical instruments).
5. Practice, Patience, and hobby money.
6. Pay for Youtube Premium.
7. Ali Express Account.
It is hard to get a healthy amount of thermal mass with a small iron.
Hot air and tweezers, cheap is fine.
I'm sure for someone experienced the benefit is marginal but having a bunch of probes and being able to see the waveform feels like cheating for an amateur like me.
They're not that bad. You can get a good entry-level oscilloscope from a company like Rigol or Siglent for ~$300.
A good, fast reacting multimeter is likely better thing to get than a cheap scope.
That said the cheapies might be usable for debugging audio stuff.
3.5: scrap PCBs for soldering practice that you don't necessarily want to repair.
Understand atoms and valence electrons 1st.
Get acquainted with ohms law and…
Tackle series circuits, then parallel then series parallel with resistive loads only 2nd.
If you’re feeling ambitious move on to ac theory capacitors and inductors, transformers and get comfortable converting polar to cartesian and vice versa.
Typically diodes and then transistors next.
Thats pretty much it for the low level.
Find a book that covers this stuff and avoid maxwell and the physics approach unless at some point you want to suffer / get really deep.
Also, flux. Lots of flux and alcohol to clean it up. Flux is the key to good solder joints, that and getting comfortable creating jigs. Whatever you're soldering has to remain still while the solder sets. Let the heat and capillary action do the work.
For troubleshooting power audio electronics Rod Elliott (sound-au.com) has a large number of useful articles both on simple theory (no poles and zeros) and on practical matters. Bob Cordell's and/or Doug Self's books on designing power amplifiers are good for a bit more "practical theory" (how the blocks are arranged, what goes wrong with poor design and/or a too-small budget for protection).
I don't have recommendations for radio frequency because I've not spent time with it. The ARRL (Amateur Radio Relay League) has several books that are well regarded, I believe.
https://youtube.com/@stezstixfix
https://hifiaudio.com/
Their kits come with a helpful pamphlet. I have an old hi-fi with a few annoying component failures I’d like to fix.
I’d say they’re intermediate difficulty. I’m going to start with some soldering practice kits, lightbulb replacements, and pot deep cleans. I’m reasonably confident I can get that done without killing my stereo.
One upside to this approach is that as you improve it can pay for itself by reselling the fixed items.
Find some popular piece of electronics with a fatal design flaw that’s trivially fixed with some basic rework that you can flip for $25-$1200. Do this a hundred times. Branch out.
This changes year to year but could be fixing joycons, reflowing bga’s, upgrading soldered memory on newer laptops, doing case swaps on consoles or smartphones, and as others have pointed out, lots of automotive, vintage collectible computer, or hifi work.
A plugin hakko soldering iron, a hot air reflow station, Amtech STIRRI-V3-TF flux, some copper braid, and Kester SAC305 lead free solder will get you 95% of the way there.
The financial component means you churn through hundreds of devices rather than dozens or less if you were to do it as a hobby.
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https://www.youtube.com/@EEVblog
https://www.youtube.com/@NorthridgeFix
https://www.youtube.com/@electronicsrepairschool
https://www.youtube.com/@adriansdigitalbasement
https://www.youtube.com/@bitsundbolts
https://www.youtube.com/@necro_ware
The most basic core of practical electronics repair is that there are things that should be conductive and things that shouldn't be conductive and you need to figure out how to do either.
My most recent fix was on a washing machine. After ruling out the simpler issues .. it turned out to be dry solder on the main relay on a rather hairy looking control board. Before this the drain pump had died .. it was amazing technology shipped home by someone on ebay for $20!
I've learned a decent amount with some electronics adjacent hobbies, like 3d printing, diy sim racing stuff, mechanical keyboards. Mainly just copying things other people build. Enough that recently I was able to diagnose a broken transformer in an electronic theater chair power supply.
This channel is awesome:
https://www.youtube.com/@greatscottlab/videos
I think it helps if you have a specific niche you want to play in. I stick with the era before integrated circuits became dominant because troubleshooting those is next level from replacing blown caps or whatever. Motivation is generally that I want to hear the thing I’m fiddling with and that there is usually some mechanical part of that gear that makes them interesting.
Get a desolder gun when you get a soldering iron.
Also the TechMoan guy on YouTube is fun as he shows his failures repairing things along with the successes
The Nintendo Switch Lite is a fun piece of hardware because they're cheap to buy used/broken and there are many opportunities for component-level repair.
Some great written info (specific to the switch) here:
https://www.retrosix.wiki/first-stage-boot-short-checks
https://repair.wiki/w/Nintendo_Switch
There are a lot of good videos on Youtube, for one. Louis Rossmann has some good stuff (especially his older stuff), Dave Jones has some good repair videos (intermingled with a LOT of other stuff, though), and there are plenty of other channels dedicated to electronics repairs.
Having said that... you'll need to know at least a bit about electronics (qua electronics) before going terribly far with electronics repair. Much the same way that one could only get so far at debugging and fixing code, if one didn't know something about writing code in the first place.
So... there are, again, videos on Youtube. The Vocademy channel, for one, is a great resource for general electronics theory.
And books. Don't forget books.
I'd suggest, depending on your existing knowledge level, find a couple of books on basic electronics, load up some of those videos, get some components and perfboard and a soldering iron and some basic test equipment (a multimeter and an oscilloscope are a good start) and start building simple circuits. And gradually expand the range of circuits you build to become more complex over time. More or less simultaneously, start watching YT videos on "electronics repair". The thing is, there's a difference between knowing "the theory of electronics" and having the debugging / troubleshooting skills, intuition, judgment, etc. to diagnose faults. The two things are related, but are somewhat orthogonal.
At some point, find used junk non-working electronics, either stuff friends/family will give you, or stuff you dig out of a dumpster, or buy at thrift shops, or buy off of Ebay listed as "not working / for parts only" and start trying to fix things.
So basically... "learn theory / build stuff / fix stuff" in an iterative loop. That's about the best advice I can give.
I reckon it will be valuable in the future that comes.
I agree. That's one reason (not the only reason mind you, but one) that I've spent a modest amount of money over the last year or two, upgrading my electronics lab, in terms of tools, test equipment, etc. I mean, I do this stuff for a hobby, and it's been a nearly life-long thing for me anyway. But more and more recently, I find myself thinking that the ability to repair/hack/build electronic "stuff" will be a skill with serious value. I just wish I had more time to commit to it.
Beginner
* Get a Miniware TS101 USB C soldering iron, some solder, solder wick, flux
* Get a mediocre multimeter
* Do a little soldering assembly kit to learn how to solder, there are some good NASA manuals and videos to learn techniques and you won't need to do as good a job as they do
* Learn how to identify and replace broken capacitors
* Learn how to replace power and USB connectors
* ^ (a huge proportion of things that are fixable at all are going to be those two)
Intermediate
* Learn about static (ESD) safety, get the equipment and supplies to prevent frying things yourself
* Get an arduino or other low cost prototyping board and learn to program it and do little projects
* Find some broken consumer electronics with guides on https://www.ifixit.com/Guide and try to fix them, these things are often less about "electronics" and more about glue
* Read the parts of Zen and the Art of Motorcycle Maintenance about maintaining and fixing things
* Read https://www.eevblog.com and watch https://www.youtube.com/eevblog for information and inspiration
Advanced
* Get an oscilloscope and bench power supply, learn how to probe and analyze signals on boards
* Figure out yourself what next steps to pursue, you should be able to at this point, or at least to ask more specific questions
For any product with microcontrollers, you might be able to locate JTAG connections and use that to debug some of the functionality. But that area requires even greater amount of knowledge and experience.
But yes, if you are talking about replacing BGA packaged high-end chips in very complex devices, there's a threshold were it becomes very difficult. But even then, if we watch some of what the different folks on Youtube accomplish repairing smartphones, laptops, etc., we'll see that some of these guys can achieve some pretty impressive results even without fancy labs and complete schematics, etc. Not everything is repairable of course, but I don't think pursuing this path is exactly "tilting at windmills" either.
If you foresee supply chain or financial difficulties where you are, enough that people will need to keep old machines running...
* Question: Are you thinking for keeping your family's device's working, and maybe teaching them? Or for operating a primary business, or side business?
* If you're currently financially comfortable, you might want to quickly learn what tools and supplies you'll need for several(?) years, and see whether they're currently available and inexpensive where you are. (For example, temperature-controlled soldering irons, desoldering device or braid, a multimeter that has all the features you expect to need, misc. screwdrivers, many sizes and types of security bits, smartphone repair spudgers and suction cups, an assortment of various high-quality capacitors of various specs, an assortment of hookup wire, fuses. Some common parts, like mains power cords, are easy to find from unfixable devices.)
* Repairing power tools and small&large appliances, is a bit different than repairing old radios and televisions, is a bit different than new radios and televisions, is a bit different than older computers, is a bit different than newer computers.
* If this includes keeping old computers working, you might want to think about what kinds, and what parts will wear out and be difficult to cannibalize. For example, some laptop models will need their fans replaced eventually, and then maybe their keyboards. Laptops made 15(?) years ago will soon need new backlight tubes and/or inverter boards, or new panels (possibly LED-backlit, plus the electronics to drive them). Most PCs and laptops will need new thermal compound eventually, especially if you do some kinds of work on them. Fortunately, most PC parts can be cannibalized easily.
* Repairing smartphones requires special parts and supplies, and in some cases might be impossible. You might think ahead to which ones you expect to want to repair, watch (and try to youtube-dl) the tutorial videos, and
* For a business refurbishing old laptops, you might want to start saving repair PDFs now, in case the Internet gets fragmented. For Lenovo/IBM ThinkPad laptops, search for "Hardware Maintenance Manual" and the model numbers.
* Try to avoid IoT, and computers and software that depend on some company's servers to keep running. And move to Linux (such as Debian Stable) if you haven't already. WiFi routers should be running OpenWrt for security and longevity. And consider whether you want to focus on a particular ecosystem of smartphone and tablet (iOS, proprietary Android, "alternative firmware" Android) that you expect to be able to source enough devices for and keep working.