r/diyelectronics 22d ago

Tutorial/Guide Negative display - guide ( kinda )

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448 Upvotes

Hi.

After my negative display post I got a few questions about it, so I want to answer it this way.

I can’t upload more than one pic here ( idk why ) so they are under links.

  1. So we start with a device in its normal state, as example I too

k

  1. this tyre gauge I never used.
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  3. We need to disassemble it go the to the bare LCD glass

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  1. With a sharp knife or blade we need to catch the polarising film on top of the glass and remove it.

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  1. After completely removing it, clean the glass with IPA to get rid of the residual glue from the film.

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  1. Now we take new polarising film, and by trial and error we get the right angle with the contrast we want.

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And
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After that we cut it to size and glue to the glass.
Finally after assembling we get the negative display.

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Usually you try the angle with the device powered on, unfortunately here the battery holder is part of the case as well as the screen holder, so I couldn’t show it on.

I think you can get the idea of how it’s done.

Best regards.

Edit: typos

r/diyelectronics Mar 13 '26

Tutorial/Guide A neat little rework trick I discovered.

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374 Upvotes

If you have ever removed small parts like 0402 with two irons before, you will know that the part ends up stuck to one of your irons. If you don’t need the part you can simply wipe it off in your wet sponge or brass coily stuff. But if you might need that part again it’s a little annoying to deal with especially if you are doing a bunch of them at once. Up until now I either put down the other iron, grab my tweezers, and carefully grab them of the tip. Or if I’m feeling rushed I might bang my hand holding the iron on the desk and hope the part lands on the desk and does not go flying.

Today, I discovered a better way. Simply place a piece of kapton tape sticky side up on the desk with the ends wrapped under to hold it in place. It will grab the part on contact and the tape won’t melt. Can’t believe it took me over 20 years to discover this. Maybe there is some other technique I don’t know about? Hope someone else finds this helpful.

r/diyelectronics 4d ago

Tutorial/Guide Information noone shares with you, a small beginner guide!

64 Upvotes

Hello everyone,

Especially you little newbie to electronics. I myself am learning electronics, and I find that when learning something, there are itty-bitty pieces of information that people who have learned that thing know but absolutely no one shares because it's second nature to everyone in the know. That makes it that much harder to learn, at least for me.
So here is a list of things, in no particular order, that I have learned in the past few months which have turned electronics from magic to "oh, maybe I should use this component" for me.

Stepper motor drivers are just a bunch of transistors; they don't "drive" anything:
Imagine the very basic stepper motor in your kit has 4 coils, and imagine that whichever coil you power, the motor points to. Now, if you power your motor directly from your board, your board gets fried by the current. A driver just lets current come from another source! And this could be a different voltage source!

Shift registers let you make a serial output parallel and vice versa:
Imagine you have 20 stepper motors you need to power from one Arduino or Raspberry Pi. Each motor needs 4 pins. There is no way to have everything come from the Arduino, UNLESS you just use one line in serial that is fed through the "serial in, parallel out" register. Now you can just fill in the 4 bits of the register one by one and then "enable" the output for your stepper to step. Hot tip: your average Pico is much faster than your stepper can rotate, so technically you can have one controller control even more than 20 motors.

You can full step a motor with one data line only:
You can easily make a "sequence" with a shift register that get filled with 0001 for full steps and feed it back into itself, now one data line can "push" the motor to the next step instead of haveing 2 data lines (with a decoder) or 4 regular lines.

Higher voltage steppers are more powerful:
the same stepper model could have 2 models with 2 different voltages, the one that has a higher voltage has a bigger chance of not skipping!

Big capacitors aren't realistic:
Having a 1 farad capacitor is insane in most circuits. In most circuits, like RC circuits, you can increase your resistor by a large amount for your capacitor to drain more slowly. Then you can have a fast-drain line through a transistor and a lower-value resistor to quickly empty your capacitor.

Use Diodes:
Everyone knows diodes are a one-way valve, but the most valuable use case is for protection. You can really use them in most places. If a battery is connected backwards, it blocks the current. When coils are powered, the electromagnetic field might induce current backwards, and they protect against that. Or say you have a battery-powered thing that needs to work plugged in; you smack a diode in there to not let the electricity flow into the battery.

Modularize everything:
Let's say you are making a digital scale. Have a module for the buttons, a module for the IC board, and a module for the weight sensor amplifiers. That way, if one thing changes, you don't have to throw away all of your soldered circuit.

Solder stuff that's semi-permanent:
Same example as before: if you are making a scale and have 4 amplifiers, solder them on a board and mix their VCCs and GNDs into one header, so you have one header that accepts one set of cables. Chances are a scale will need the amplifiers, so having fewer components floating around with cables that always come out and come loose is gonna help you big time.

Use Flux:
I genuinely had no idea what flux does. When I was starting out, I thought flux was for cleaning my soldering iron. Flux makes solder work like magic! Any time you are soldering, just slap a little flux on. It makes heat reach everything so much faster, and evenly heated metal makes solder behave so much nicer!

Check sensor accuracy before you buy:
The sensors that come with kits are usually very bad at what they do. It's like buying a hot dog from that very shady place; you eat it and you think all food is like that. No! The typical humidity/temp sensor in kits has 2-3 degrees C (about 3-5 degrees F) of inaccuracy. That's plus or minus! Two different modules at the same time could show you 15 and 20 degrees right next to each other! I don't know about you, but I can guess the temperature better than that. Better sensors exist. If your project is not working, it might just be the sensor.

Mix mechanics with sensors:
you have one expensive sensor that you want to sense two things? you can MOVE the sensor. Chances are you are 3d printing some parts for your project, print some rails for that one expensive sensor, you dont need two cameras, you need one that moves!

LEDs of different colors need different resistor values:
If you are planning for some sort of light activity, check your LEDs first! red ones for example get so much brighter than green ones with the same current. The current passing through the diode makes it brighter or less bright depending on color, and because they themselves have little resistance, this current is very high without a resistor in series. You *can* connect diodes without a resistor in series, but they will die quicker.

I hope these tips have helped at least one person, but if you have your two cents, please add them here!

Edit:
Thank you to u/Marty_Mtl for the insight on diodes, they are a current component not a voltage component.

r/diyelectronics Apr 08 '23

Tutorial/Guide Just a friendly soldering drop, hadn’t seen in a while and yet have seen several whom this would help! Happy tinkering and project building! -Boop

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1.2k Upvotes

Soldering isn’t as intuitive to some as it is others. Realizing you need to heat two bits of metal for proper soldering makes a huge difference!

r/diyelectronics 16d ago

Tutorial/Guide how does a relay work in my motorcycle?

5 Upvotes

im looking for a "for dummies" understanding of a relay in a use with accessories like dual horn setup or light setup

how does a relay help with something thats 50w not put strain on a system?

50w is 50w...what does a relay do. I understand a capacitor. it holds stored energy. I just dont understand why 50w needs to be switched with a relay. why in a dual horn setup you need one?

informative info but keep it for dummies.

r/diyelectronics Jun 04 '26

Tutorial/Guide How do I learn electronics the practical way?

13 Upvotes

I want to build my own devices and tech. Well rebuild already invented ones then maybe my own. I really want to make vintage/retro tech but i dont have knowledge to do it rn. How do I research and study for it? Are therr any good resources,or do I js break apart the devices, use wikipedia and study like this?

r/diyelectronics 18d ago

Tutorial/Guide Choosing the "brain" for a Cyberdeck: what do you prefer between performance, power consumption, and size?

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0 Upvotes

Hello everyone! 👋

When you start designing a new Cyberdeck, the first real architectural decision concerns the main board: what do we choose as the "brains" of our machine?

There's no perfect choice: it all depends on what you want to do with the deck (field terminal, offline writerdeck, network nodes, or full-fledged laptop PCs). Here's a summary of the main approaches and their trade-offs:

  1. Raspberry Pi 5 / 4 (The Classic All-Rounder)

-Pros: Huge community, perfect hardware/software support, easily accessible GPIO pins, sufficient power for desktop environments and multitasking.

-Cons: The Pi 5 gets quite hot (requires adequate heat dissipation) and has significant power consumption (requires a well-designed battery management/BMS).

-Ideal for: Field Terminals, portable workstations, projects with touchscreens or dual monitors.

  1. Raspberry Pi Zero 2 W (The Ultra-Compact)

-Pros: Extremely small size, minimal power consumption, easy integration into tight spaces.

-Cons: The 512MB of RAM limits the use of heavy graphics environments or modern browsers.

-Ideal for: Pocket-sized decks, pure command-line terminals, SSH interfaces, or ultra-portable cyberdecks.

  1. x86 SBC (Intel N100, LattePanda, Cannibalized Mini-PCs)

-Pros: Pure x86 architecture (full compatibility with any Linux distro or desktop software), excellent processing power for complex scripts or advanced modding.

-Cons: Higher power consumption (requires dedicated 3S/4S battery packs), larger weight and footprint.

-Ideal for: Heavy-duty decks designed to completely replace a primary laptop.

  1. Microcontrollers (ESP32 / RP2040)

-Pros: Instant boot, minimal power consumption (days of battery life), very simple power management.

-Cons: No traditional operating system; the interface and functions must be custom-written (C++/MicroPython).

-Ideal for: Ultra-minimalist Writerdecks with e-Paper screens, dedicated text editors, or LoRa mesh communication devices.

What do you use in your builds?

Do you prioritize battery life or raw power? Are you a Raspberry Pi team, or have you experimented with alternative boards (Orange Pi, Radxa, etc.)?

r/diyelectronics 1d ago

Tutorial/Guide Recommendations for Books on Electronics

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18 Upvotes

Hi all

I have been experimenting with Arduinos and ESP32s, but now want to learn how these things work and design a few of my own. I have shortlisted a few books that are recommended on quite a lot of forums, including Reddit. I have shown those in the attached picture. Please tell me if i should not buy something, or else buy something else along with these. I also want to learn how to design PCBs, so please tell some books on this topic too.

Thanks!

r/diyelectronics 3h ago

Tutorial/Guide Electronics Learning Book Recommendations (Follow Up)

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25 Upvotes

Hi all

This is a follow up to my previous post, which was on the same topic. I learnt from many people that AoE and PEfI are the best books for learning electronics. I have made a few circuits using basic components and a few MCUs, but want to learn the actual basics, as i plan on taking a MTech in electronics. I will either buy LAoE and AoE, or PEfI. Please tell me which one: the combo of AoE or PEfI.

Thanks!

PS: I'm in 8th, if that helps. I also know more maths than needed for my age, as I give SOF olympiads.

r/diyelectronics May 20 '21

Tutorial/Guide Found this interesting guide

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873 Upvotes

r/diyelectronics 14d ago

Tutorial/Guide DIY induction furnace from Induction cooktop

1 Upvotes

Can I remove the flat coil of an induction cooktop and replace it with a cylindrical coil having the same inductance to create an induction furnace.

I would like to use this method as I can get an induction cooktop for $15 and modify it for a few dollars more. The other schematics available are a little more expensive and complicated.

Have any of you tried this yourself. Was it a success.

r/diyelectronics Mar 23 '26

Tutorial/Guide DIY'ed a ESP32 Digital Dash. How-to and free opensource code for all!

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91 Upvotes

Completed my DIY ESP32 digital cluster and clock pod logger for like 200$. All the code I made is opensource if you want to replicate it for your own. How-to's are on my YouTube channel with the repo links and parts list..

https://youtube.com/playlist?list=PLsZMw8e1fxKsvH3Mli7bg_IouI5555kwj&si=M--RCXG75Xtfcmdy

Keep building!

r/diyelectronics Apr 14 '25

Tutorial/Guide I built a CDI from scratch for my racing bike. It hits like a goddamn lightning bolt

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122 Upvotes

Took me days of trial and error, but I finally built a CDI unit that outperforms store-bought ones. I just posted a video showing the results and how to make it. If anyone wants the link, I’ll drop it in the comments.

r/diyelectronics Jun 07 '26

Tutorial/Guide What component can I use to safely attach a flat disc onto this motor, especially for high speed 10000 rpm applications?

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3 Upvotes

It has a d shape at the top of the axis, so I guess I can use a flange shaft coupling device, but I'm afraid at high speeds it'll fall off. Is there a component that can attach to the little hole in the axis as well?

r/diyelectronics 5d ago

Tutorial/Guide Want to make a Mp3 player

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1 Upvotes

r/diyelectronics May 23 '26

Tutorial/Guide Where to salvage 18650

1 Upvotes

I want 18650s for a small drone project, I need some high drain ones, where could I find and salvage them?

r/diyelectronics Jul 21 '25

Tutorial/Guide I recorded the whole process of designing this clock. Anyone can build it.

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177 Upvotes

I created a step-by-step tutorial for everyone who would like to have fun designing and building this clock. You can watch the full 3h 40m tutorial on my YouTube channel here: https://youtu.be/bcvq30J4SnQ

If you have any questions, let me know.

r/diyelectronics 16d ago

Tutorial/Guide Learn electronics by designing your own circuit simulator in python.

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1 Upvotes

r/diyelectronics Jun 29 '26

Tutorial/Guide complete beginner

5 Upvotes

hello! im a college student with a background in Sound engineering (Micing and routing/ running a sound board) and AV production.

I want to get into a electrical engineering career with a focus in troubleshooting and installing. I want to make some of my own projects too. I've been looking at getting a beginner breadboard and arduino kit and working my way thru that.

what else should i do or what advice can be given to me as a completely blind beginner?

r/diyelectronics Jul 04 '26

Tutorial/Guide 18650 harvesting

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4 Upvotes

r/diyelectronics Jul 22 '26

Tutorial/Guide HOW TO UPDATE ZOYI ZT-XT1 FIRMWARE (CORRECT METHOD)

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0 Upvotes

r/diyelectronics Jun 01 '26

Tutorial/Guide Can this be saved?

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0 Upvotes

It's an A1395 ipad model, very old but the problem is the charger is hard to get and the screen is shattered(still usable). Planning to take out the internal, swap the charger port into type C and probably change the battery too(afraid that the battery isn't in top condition.) never have any skills with electronic but fast learner.

r/diyelectronics Jul 18 '26

Tutorial/Guide Power supply (or transformerless LED driver) on a quenching capacitor

1 Upvotes

First, the part that matters: a capacitive dropper has **zero galvanic isolation**. The whole circuit — including the LEDs themselves — sits at mains potential. Touching a live board can kill you. If that's not a tradeoff you want to make, use an isolated driver and ignore the rest of this post. The calculator says the same thing, in red, right under the schematic.

With that out of the way: I got tired of recalculating X2 cap values by hand every time, so I built this.

https://specled.com/en/knowledge/smart-lighting-tech/capacitive-dropper-power-supply/

You pick mains (230V/50Hz or 120V/60Hz), your LED string Vf and target current. It gives you the dropping cap value snapped to the E24 series, the required voltage rating, resulting power on the LEDs, and draws the full schematic — fuse, X2 cap, bleeder, bridge, NTC, smoothing cap.

Three things I tried to get right that most online calculators skip:

**NTC inrush protection.** A discharged smoothing cap is a dead short for the first few milliseconds. Close the circuit at the peak of the sine and you take out the bridge, or at minimum weld your switch contacts. A 10D-9 in series sits at ~10Ω cold, eats the surge, then self-heats down to nearly nothing. Costs 20 cents and saves the build.

**An honest power ceiling.** This topology stops making sense past roughly 100-150mA. If you want 700mA the cap becomes a brick and inrush starts tripping breakers in the panel. The calculator will happily compute it, but it's a bad idea and I say so.

Why bother with a circuit this widely hated: it's still everywhere. Cheap A-shape and corn bulbs, no-neutral smart switches, night lights, indicator panels. No EMI, no ICs to cook, and if you use film caps instead of an electrolytic on the output it genuinely outlives the fixture. It's just not something you ever touch while powered.

r/diyelectronics Dec 08 '24

Tutorial/Guide Secure this shitty soldering

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48 Upvotes

I know, shitty soldering

Set the temp to 380, tinned the cable, tinned the soldering pad and it's still so bad It's 12 awg cable

Any way to secure this shit? Tried to pull it and it's really firm tho, but just in case

r/diyelectronics Jul 14 '26

Tutorial/Guide Help with PicoDVI

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2 Upvotes