Electronics Without the Smoke
Like Duolingo, but for Electronics Without the Smoke. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
For the part of you with thirty open tabs that never became anything.
A short one: 11 levels across 2 sections, about 22 minutes end to end, roughly 4 days at five minutes a day. It moves through Power and Protection and Reading and Troubleshooting. It starts from scratch.
Free forever · No credit card · iPhone & Android

Key ideas in Electronics Without the Smoke
- Voltage is the pushing force provided by a source like a battery
- Current is the actual volume of electricity flowing through the circuit
- The connected device determines how much current flows based on the supplied voltage
- Power supplies provide a fixed voltage but only supply current as demanded
- The amperage rating on a power supply is its maximum available capacity, not a forced feed
- A 1A device plugged into a 10A supply will safely draw only 1A
- Voltage must match the device's specification closely
- Excessive voltage forces too much current through sensitive internal parts, causing overheating and burnout
- Unlike excess current capacity, excess voltage cannot be safely ignored by the device
- A short circuit happens when power connects directly to ground without passing through a working load
- Without load resistance, current spikes to dangerous levels almost instantly
- Direct-current circuits have designated positive and negative pathways
- Sensitive chips and diodes cannot tolerate voltage applied in reverse and fry almost immediately
- LEDs provide almost zero resistance on their own
- A series resistor is necessary to choke the flow of current down to a safe level
- Electrolytic capacitors have strict positive and negative orientation
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives Electronics Without the Smoke the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
What is electrical current in a working circuit?
Get it right to open this lesson and 10 more in the app.
Where Electronics Without the Smoke takes you
Decode confusing jargon, avoid classic rookie missteps, and build circuits that actually work. Learn the essential rules of voltage, polarity, ground, and testing before you plug in.
- 1
Power and Protection
- Voltage, Current, and Power Supply Traps
- Polarity and Fragile Components
- 2
Reading and Troubleshooting
- The Mystery of Ground and Floating Pins
- Schematics, Breadboards, and Multimeter Checks
2 sections · 4 units · 11 levels. Built to play, not to enroll.
You pick the voice
Electronics Without the Smoke is taught in the The Bestie style: your friend who just gets it. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start Electronics Without the Smoke today.
Download Tomo, search Electronics Without the Smoke, and play your first lesson in under a minute.