Not a page about electronics — a bench. Drag either slider below and the current, the colour bands and the LED all respond, because they are solved and not drawn. The rest of the site works the same way: 149+ plain-English component pages, 46 calculators that show their working, 9,000+ past papers and free DCET mocks.
Over the LED's 20 mA rating — it will be bright, briefly. Go up a resistor size.
Real datasheets are 40 pages of graphs written for people who already know the answer. ElectroHub is the opposite: every component gets one clear page — what it does, how to read its markings, which one to buy, the pinout, how it fails and how to test it. Calculators, converters and a quiz round it out into a complete bench-side companion that works with the Wi-Fi down.
Prepping for a lab viva or electronics exam? Every page doubles as revision notes, and quiz mode drills the questions examiners actually ask.
Mid-build and can't remember which way the electrolytic cap goes? Pull up the pinout, check the polarity, decode the bands — done.
A fast second brain at the bench: failure modes, multimeter test procedures and code decoders without digging through PDF datasheets.
No tutorials to sit through. Open it, look things up, get back to building.
Browse 14 categories or type a part name like "555 timer" into search and jump straight to it.
Browse componentsWhat it does, key specs, markings, which one to buy, the pinout, how it fails and how to test it with a multimeter.
Try search46 calculators that show their working step by step, and converters that flip units both ways. No spreadsheet needed.
Open calculatorsQuiz mode turns the library into practice questions per category — ideal for viva prep and interviews.
Start a quiz100+ components across 9 categories — specs, markings, how-to-choose, pinouts, failure modes and test procedures in plain English.
A guided circuit solver and 45 syllabus-aligned tools with step-by-step working — from Ohm's law and star-delta to three-phase power, op-amps and the 555 timer.
Find any part by name, type or spec in milliseconds. Filter by availability so you only see what's ready to read.
Flip between µF and nF, mA and A, dBm and mW without thinking twice — bidirectional converters for the units you actually use.
Practice viva and exam questions per category. Great for lab exams, interviews and keeping the fundamentals sharp.
Installable as a PWA. Once loaded, the entire reference runs without a network connection — perfect for the lab bench.
ElectroHub doubles as a study hub — 9,000+ previous-year papers, real DCET mocks with per-topic analytics, the official syllabus and printable revision sheets. The timed mocks and analytics other platforms lock behind a subscription are free here — no login, no ads, and they keep working offline.
9,000+ question papers from VTU, GTU and Anna University — organized by branch, semester and scheme, linked straight to the source PDFs.
Official KEA papers (2023–2025) as timed, exam-pattern mocks with instant scoring, explanations, score trends and weak-topic analytics — the paid feature on other platforms, here free and offline, no login.
Verified module lists for Karnataka Diploma (C-20) and VTU 2022-scheme EEE, checked against the official documents.
Recommended textbooks mapped subject by subject — the standard titles worth reading, matched to your syllabus.
One-page reference sheets — formulas, resistor color codes, capacitor codes and SI prefixes — formatted to print.
Every law you get asked in a viva — stated formally, translated into plain English, with formulas and diagrams.
Mock attempts and quiz progress stay on your device — sign in (optional) to sync them across devices.
From passives to power distribution — organized the way you actually look for things.
Resistors, capacitors, inductors — the building blocks
Diodes, transistors, ICs — the brains
Relays, switches, motors — things that move
Fuses, breakers, TVS — keeping circuits alive
Turning the physical world into signals
Batteries, cells, supplies — the juice
Connectors, headers, wires — the plumbing
Transformers, contactors, busbars — the big stuff
Induction motors, alternators, big transformers — the machines chapter
Lamps, tubes, LED drivers, ballasts — making light
Antennas, filters, amplifiers — the wireless chain
Heatsinks, fans, Peltiers — keeping the smoke in
Multimeters, scopes, meggers — the instruments that find faults
Arduino, ESP32, Raspberry Pi — dev boards
Stop tabbing out to a spreadsheet. A guided circuit solver and 45 purpose-built calculators cover the math you do every day — every answer shows its step-by-step working, and every code decoder works both ways.
The whole reference is one tap away — and once it loads, it's yours offline too.
Open ElectroHub — it's freeTip: use your browser's Add to Home Screen to install ElectroHub like an app — it keeps working with no connection at all.