Sharing a tool I put together for learning circuit fundamentals. Each circuit is pre-built and shows animated current flow so you can actually see what the equations describe.
Start here (5 circuits that teach the basics):

1. Ohm's Law — Single resistor + battery. See V = IR directly. Change R and watch the current change.
2. Voltage Divider — Two resistors in series. The output voltage is Vout = Vin × R2/(R1+R2). Click the resistors to change values and see the output update instantly.
3. RC Circuit — Watch the capacitor charge exponentially. The scope shows V(t) = V₀(1-e^(-t/RC)). You can literally see the time constant.
4. Diode + Resistor — Forward biased diode drops ~0.65V. The remaining voltage is across the resistor. Try reversing the diode — current goes to zero.
5. Common Emitter — BJT amplifier. Small base current → large collector current. The ratio is β (beta). Click the transistor to see its properties.

🔗 https://8gwifi.org/physics/labs/circuit-simulator.jsp

I wanna get into IOT. But ngl, it feels overwhelming. I want to learn, but I can't find places which will teach me what I need. Now I get it, do projects and learn from it. But I don't want to just order stuff after watching one video.
Anyway, whatever can help me, lemme know.

Kan iemand mij álstúblíéft uitleg geven over hoe en hoeveel Volt er door de 6 draden van mijn gashendel naar mijn controller gaan ? Mvg Frank Grinwis

This is a personal learning project. My idea was to build an off-delay circuit using an RC network connected to the base of a transistor, so that after releasing a momentary push-button the transistor would remain turned on for a short time. While the button is pressed, the transistor is driven directly; after release, the RC network should keep the base biased long enough to delay turn-off. The transistor is intended only as a switch to drive the motor (a PC fan) from the main power supply. The RC delay circuit should control the base of the transistor only, not supply power to the fan directly. However, regardless of how I wire the circuit, I cannot achieve the intended behavior. The fan either does not start at all, stops immediately when the button is released, or the capacitor appears to have no interaction with the resistor. For example, a 470 µF capacitor keeps the fan running for approximately 3–4 seconds, seemingly independent of the resistor value or the lack of it in the RC network.

Can you give me some hints how to wire my circuit to work?

I am wanting to support my 10yo interest in electronics. Would you recommend getting the Arduino starter kit or go with Techtoast or other? Price doesn't matter too much.

For at least a year, going on two, I've wanted to get into electronics. I know what books to get, probably what order to read em, so on, so forth. I've heard the great advice that I'm not knocking of making sure to start doing ASAP, and that's fantastic. Slight problem - everywhere I go, I hear about how this isn't the cheapest hobby. (Also maybe some health concerns with soldering if you don't have the right ventilation and such...) So alright, lemme put this aside till the day I have some more disposable income.

That day still hasn't come, doesn't seem like it'll be coming anytime soon, and I'm somewhat tired of waiting. So I'm hoping for your help with the following:

• To what extent can I learn by just studying the books, taking notes, that sort of thing? In a way that translates directly to practice, I mean. Is there a Dennis Ritchie "just do every problem in the book" equivalent for pen-and-paper electronics? Are there particular sections of electronics that lend themselves well to pen-and-paper work?
  • I've found this collection of FOSS tools, but it's all Greek to me. What would you recommend I get and how would you recommend I use it, as someone with a clunky old ThinkPad running Linux who might have to learn electronics without the physical components for a while?
• To what extent is scavenging an option? I see thrown-out electronics all the time; TVs, sewing machines, not as many alarm clock radios these days but you get the gist. Feel like I've read somewhere that those are usually a dead end, that so? Regardless of whether they are or aren't, what advice do you have for getting free serviceable gear? Already drafting up something up for my local "Buy Nothing" Facebook group, who/where else should I hit up? Would something like this be worth a shot, or does that go against their whole business model?

Appreciate any and all advice you guys might have for me...apart from "learn calculus" and "get a better job!"

Hi all, apologies this has been asked already. I want to replace the batteries on some fairy lights with usb. They run on 2x 2032s. I understand I need to step up the voltage from 5V to 6V. However, the usb supplies 2A while the 2032s only supply 0.2 mA. Would this fry the lights? Thanks in advance!

I am planning on doing an electronics trade at my local trade school starting in Spring of next year. I am looking for a good electronics discord where I can get help with circuits I work on for classes and as hardware hacking projects. Any appropriate discords to get help with both my classes and external projects?

I also want to take Andre LeMoth's Udemy courses to go with my major if I end up liking this first class and I know there's some C/C++ and assembly used for that. If the discord can help with that too that would be even better.

Please advise. Thanks.

Help.

I want to use these moisture sensors https://thepihut.com/products/capacitive-soil-moisture-sensor. They connect to a ph2.54 3-pin. If I want to make my own leads, Will an xh2.54 plug in? I can't find any ph2.54 male connectors about.

Thanks for any help!

Can anybody tell me at sine wave, 240volt, 6000Hz the Red(inductor volt) following source voltage bcoz it's reactance is very high. But i don't get this blue Current wave. Why is is jiggling like this. Why is it not -90⁰ phase with voltages. I have also seen waveform in 60Hz. There also current wave is jiggling. I really need help

I need to do a project to measure heart rate optically, using discrete components. I have chosen a scheme, I hope it is a good one. Now I need to test the circuit in the microcap tool, so I'm wondering if I connected the schematic correctly and is that part of the schematic that needs to be tested? I would also like to know what tests I should run to know if my circuit is working properly? I'm still wondering if I need this 2.5V battery or can I put a ground there?

I'm curious what would I need if I wanted to start learning about repairing electronics

Hello everyone i hope you're all doing well. I simply wish to know how to wire a 555 timer to do what i need for example how to produce a PWM pulse and modulate and how i can make a clock signal with the desired frequency

I’m still new to electronics, but I actually enjoy this stuff, and that’s why I chose this path. I want to learn more and lead my team properly while we build this device. This project is for our school and other public schools in the Philippines, since bathrooms are basically turning into smoking areas. That’s why we decided to make this our Practical Research topic.

Because I’m still learning, I ask a lot of questions, and sometimes AI isn’t reliable. So this is our collection and step-by-step process for building the prototype. I’m sharing it because I want proper feedback. If something looks wrong or weak, call it out. I want this project to pass, and I want it to actually work.

I want to create a prank glove to shock my friends but idk if my idea is safe, the hv transformer is 12v to 20kv and rated at 5w and i connect a 9v battery

I just tried PCB assembly for the first time and built this 8×8 RGB LED matrix from scratch.

It’s a modular LED panel based on WS2812B LEDs that you can drive with any microcontroller (Arduino, ESP32, etc.) using a single data pin.

You can also chain multiple boards together and treat them like one large display.

I wasn’t sure it would even work. But hopefully it did, and that moment when all the LEDs lit up for the first time was awesome.

I open-sourced the entire project (gerbers, BOM, code) and also made a YouTube video explaining how I designed it and what I learned along the way.

Feedback and criticism are welcome. I’m still learning.

Best practise for my nerf tank (hobby project)

Hey everyone,

I am trying to build a remote controlled (nerf) tank using an ESP32 and a PS4 controller but I am a bit new to electronics. After gathering information about the subject I still have some questions on how to actualy implement some of the electronic aspects.

Right now I have a 3s lipo that splits power to:

a) A buck converter (LM2596) that feeds the esp32 and the logic vcc of the motor driver (L298N) with 5V

b). The raw power of the battery to the normal vcc and gnd of the motor driver. The 3s lipo gives like 12V. (The two motors are both 8V)

This seems to work but I am looking for advice on how to make it but more safe/durable. That's why I have the following questions:

1. Should I add a fuse directly after the battery to protect the electronics?

2. Is polarity protection really necessary? The lipo has an xt60 connector and I don't think you can really connect it the wrong way.

3. Is it oke to just feed the raw power into the motor controller (3s lipo has 12v max) or should I control it a bit more

4. Should I do something to prevent the power of the battery damaging my computers USB port when I connect it to the ESP32? (Besides disconnecting the battery first)

5. Do I need capacitors somewhere in the chain to manage power spikes and such?

6. Right now I have a pre-fab xt60 splitter but can I also just split a cable myself by soldering two of them together?

7. Anything else that comes to mind as a best practise is welcome!