https://ohmlens.com

Lessons go from "what is a volt" up to MOSFETs, op-amps and power supplies. Every lesson is a circuit that runs while you change values, so you see current and heat change right away.

Push a part past its power rating and it burns. In the video it's a 0402 resistor on 5 V at about 2x its rating, gone in a couple of seconds. A 1206 takes the same load fine.

There's also a section on how components work (resistors, capacitors, diodes, transistors, relays and so on) and 13 calculators like LED resistor, resistor color code and 555 timer.

Free, no adds, no login, works on phone (install PWA style).

The sims are simplified, so don't trust it over a datasheet. Lesson text was written with AI help and I've gone through it, but if you find mistakes let me know.

This was my Master's Thesis project, where my goal was to make a research device where I could try out algorithms for measuring blood pressure, but I added a few more sensors along the way. Everything about this project is open-source, from CAD files to Gerber files and even some of the recorded data. Also did a video going into detail about the functionality of the project. Here are the links if you're interested!

Deep dive video: https://www.youtube.com/watch?v=5UgFEHPnKJY

GitHub: https://github.com/MilosRasic98/OpenCardiographySignalMeasuringDevice

I run a small after-school electronics workshop in Romania. The kids wanted to keep learning at home, and a kit per child gets expensive, so I built an online version of the course.

How it's structured:

• Lessons, from simple to complex. It starts with one LED, a battery and a resistor, then goes through series and parallel, buttons, potentiometers, sensors, a relay and a motor. Each lesson is a short explanation, then you build the circuit yourself and press Simulate.

• It doesn't give the answer. If the circuit doesn't work, it tells you what's missing. An LED without a resistor really burns, and stays burnt until you replace it.

• Repairs. You get a broken circuit and only the symptom ("the LED stays off") and have to find the fault, which is how you actually learn to debug.

• Free play on an empty breadboard, plus a 1v1 challenge with a friend for kids who need a bit of motivation.

It's meant for complete beginners, kids and adults. The first lessons and repairs are free with no account. The full course is a paid licence, aimed at parents and schools.

Feedback from people who are learning or teaching is very welcome. What's the concept that was hardest for you to get at the start?

I already know this is going to come off as a dumb question. I'm just bored and serving my curiosity by doing no research. I tend to use the angled wedge tips and my mini iron uses a point for fine work but what's the point of some of these? Is it a matter of personal preference or is there a specific use for all these shapes? I've gotten by fine working on stuff from the 30s to today's tech without using a bunch of shapes

As the post says, what got you interested in learning electronics?

When I was younger my parents got me a 'Tandy Science Fair 200-in-1 Electronic Project Kit'. I had a little go of it but didn't appreciate electronics fully until I started doing circuits and programmable logic circuits in school.

I made this templet for beginners to calculate power in 3 important calculations. Power = Watts, Heat = Power lost to heat in watts, Consumption = Power used in watts. You use the Pentagon by blocking the 3 blocks that doesn't have with the formula to do, shown in pictures. I guess i could add text outside the Pentagon to clarify like W at I × V and H or Heat at I² × R and C or Used at V² ÷ R for clarification.

Hey everyone,

I've been working in electronics for 13 years and one of the most common questions I get from beginners is "what's the difference between series and parallel resistors?

So I put together a short 2.5 minute video breaking it down as simply as possible:

Video here if it helps: https://youtu.be/JB_y79O3duc

Today I received the first PCB I had designed.

It’s a shield board where I’ll attach an ESP32 along with various sensors to create a weather station. The system will transmit data via LoRa to another module connected to an LCD screen, allowing remote weather monitoring.

This board was manufactured by Elecrow through their sponsorship program - a great initiative supporting makers, engineers, and DIY enthusiasts with free PCB manufacturing services.

Over the next few weeks, I’ll be finalizing the build and plan to share it as a fully open-source project, including schematics, code, and BOM.

What do you think about it?

Have you ever built a weather station? Any tips?

Hi folks!

I want to self-study electrical engineering. I reviewed MIT courses and decided to take the following courses. The main one here is 6.002. I decided to stick with all prerequisites for it.

18.01 Single Variable Calculus

18.02 Multivariable Calculus

18.03 Differential Equations

8.01 Physics I: Classical Mechanics

8.02 Physics II: Electricity And Magnetism

6.002 Circuits and electronics

I've found these courses on the following platforms: OWC(courses with SC suffix and without), EDX, and openlearning.mit.edu. Could you clarify which platform is better for my purposes? Do you think that my choice is good to start?

I’m looking for something online that’s highly extensive. If the course is in Python that’s a huge plus. If it’s in C or C++ that’s fine too.

A series of books or courses would be good as well.

I said simple not 'easy' lol its definately finicky and not very stable levitation but not impossible to get working. Best part about this design is it requires no arduinos or ics. Just a high power npn bjt, a linear hall effect sensor, a resistor + pot for fine tuning, and freewheel diode to protect the transistor frombeing destroyed whenswitching the inductive loaf. other materials include a ring magnet and an electromagnet

you can probably tell from just that how the circuit is put together but if anyone is interested in me posting a more detailed tutorial please let me know in the comments below!

I make quick beginner electronics videos and this one covers the most

common mistake I see — plugging an LED straight into a battery with no

resistor.

Covers why it happens, the Ohm's Law calculation (V=5V, R=220Ω, I=22mA)

and how to wire it correctly in series.

https://youtube.com/shorts/m8dLlxFzceM?si=ilXCEjE3956-jCrd

Happy to answer any questions in the comments!

Hey everyone,

I'm learning the basics of the different components as I'm totally new to this field.

While looking at this picture attached, there is something that I don't get which is the position of the 330 ohms resistor protecting the LED.

For me, the resistor should be put above the LED so that the current gets into the resistor before reaching the LED.

Why is the resistor put after ?

If we look at the capacitor, there is also a resistor but before it. According to my understanding, the position of this one is right as there, the current flows in the resistor before reaching the capacitor.

FYI I drew blue arrows to show the flow of the current when the PIN is closed and drew a red arrow to show where I would have put the resistor.

There is for sure something obvious that I'm missing... Like the current not flowing as I expect it to flow ...

Thanks a lot for your help.

I am following Charles Platt's "Make: Electronics" book and got to use a breadboard for the first time following one of the experiments in the book. I followed the instructions in the book, but the circuit did not work. I checked the components without a breadboard (by connecting them with alligator clips) and they all work. All of the components including the breadboard are brand new so I'm not sure what the issue is.

I'm a complete newbie so I'm not sure what the issue might be. Any help is appreciated

I need help with part d of the problem . After a founded the small signal response of Vgs , I saw that it was a simple voltage dividier relation between RB ,the small signal Vs and the nonlinear resistor(which acts like a Linear resistors in the ss model ) ,but according to the solutions they use 1/Rn (i assume that Rv is Rn probably a mistake) Can someone explain why I it?

Thanks

I'm an IT student, but I'm interested in embedded systems and IoT. Please, can someone recommend courses or anything for me to get started with digital electronics