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, 61 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 search61 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 60 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.
Exam-style numericals across the whole syllabus, generated fresh every round so you can never run out — each with the full working, and each wrong option naming the exact mistake it comes from.
Every EEE experiment with aim, procedure, precautions and viva answers — then type in your meter readings and it fills the tabular column, plots the characteristic and tells you when a reading cannot physically be right. Nothing else does that half.
25 EEE, ECE and EIE projects that come with the engineering, not just the title — block diagram, every sizing calculation worked with its formula, a costed bill of materials including the spares and binding nobody budgets for, and the viva questions. Tell it your budget, weeks and lab access and it ranks what you can actually finish.
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 60 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.
No catch, no trial period, nothing to cancel. Here's the detail.
Yes — all of it, with no ads, no subscription and no paywalled section. The timed DCET mock tests with per-topic analytics, which most exam-prep platforms sell as a premium plan, are free here too.
No. Every page — components, calculators, question papers, mock tests and quizzes — works without signing in, and your progress is saved on your device. An optional free account only exists to sync that progress across your phone and laptop.
Yes. It installs as a progressive web app from your browser's Add to Home Screen or install button, and once loaded the component library, calculators, converters, cheat sheets, syllabus and mock tests all keep working with no connection. Only the circuit simulator and the question-paper PDFs need the network, because both live on other sites.
Yes, and with the engineering rather than the paperwork. Each project carries a block diagram, the sizing calculations worked through with their formulas and assumptions, a bill of materials costed including the spares, consumables and binding that parts lists leave out, an honest estimate of how many weeks it takes your team size, what typically goes wrong, and the viva questions with answers. You can also enter your budget, your deadline and the equipment your lab actually has, and it ranks which projects you can finish. What it deliberately does not provide is a report template or downloadable source code, because writing the report is your work and your marks.
Previous-year question papers from VTU, GTU, Anna University and the Karnataka diploma board (DTE), organised by branch, semester and scheme. Mock tests follow the KEA DCET pattern exactly, built from the official papers and graded against KEA's own answer keys. The syllabus section covers VTU 2022-scheme EEE and Karnataka diploma C-20.
No. Every paper opens at its original source, credited on the page. ElectroHub catalogues and organises the links so you can find a paper by subject code, but the files stay with the universities and archives that published them.
Diploma and B.E. students in electrical and electronics engineering, plus makers, hobbyists and technicians who want a datasheet translated into plain English. The component pages assume no prior knowledge; the calculators show every step of the working, so they double as revision.
Syllabus module lists are quoted from the official university PDFs and re-verified each time a scheme changes. The paper catalogue is rebuilt monthly by an automated job that also re-checks every download link and drops the dead ones. Recent VTU exam papers are the known gap — the public archives we can reach thin out after 2021.
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.