Volume III — Electronics & Communication Engineering

An electronics degree is four years of things that were understood on the day of the exam and gone within two. Not because the subject is hard, but because it is taught as a stack of formulas with the reasoning removed. You memorise that the emitter follower has a voltage gain of about one, without ever being shown why the emitter simply follows the base. You learn that a capacitor's impedance is 1/j\omega C without being told that j is there to record a quarter-cycle delay, and that the delay is the whole point.

This volume puts the reasoning back. Every formula is built from something simpler, every circuit is drawn and labelled, and every worked problem shows the boring arithmetic as well as the clever step. Nothing is quoted. If a result takes a derivation, the derivation is on the page.

The ordering is the one that actually works: charge before current, current before circuits, circuits before devices, devices before digital logic, signals before their transforms, transforms before filters and control loops, and all of it before radio. Nothing appears before the thing it depends on.

The ten parts

1. Circuit Theory — charge, current, voltage, Kirchhoff's two laws, mesh and nodal analysis, Thevenin and Norton, capacitors and inductors, transients, and AC analysis with phasors and resonance.
2. Electronic Devices & Analog Circuits — what silicon actually is, what doping does, the PN junction, diodes and power supplies, the bipolar transistor in full, the MOSFET in full, op-amps, and oscillators.
3. Digital Electronics — logic families and voltage levels, Karnaugh maps, adders and multiplexers, latches and flip-flops, counters, memory cells, analog-to-digital and back, and microcontrollers.
4. Signals & Systems — the taxonomy of signals, what makes a system linear and time-invariant, convolution made obvious, Fourier series and transform, Laplace, the Z-transform, and the sampling theorem.
5. Digital Signal Processing — the DFT, the FFT algorithm that runs the modern world, FIR and IIR filter design, spectral analysis, audio and image processing.
6. Control Systems — open versus closed loop, transfer functions, poles and zeros, transient response, stability tests, Bode plots, PID tuning, and state space.
7. Communication Systems — the channel and its noise, AM and FM, digital modulation and constellations, multiplexing, OFDM, the Shannon limit, antennas, and transmission lines.
8. Wireless & Telecom in Practice — how a phone call actually reaches a tower and a core network, how GPS works without internet, Wi-Fi and Bluetooth, NFC and RFID, satellite and fibre, and the telephone story.
9. Power Electronics & Machines — transformers and why AC won, motors and generators, batteries, wireless charging, rectifiers and inverters.
10. Embedded Systems & the Smartphone — microcontrollers versus systems-on-chip, sensors, the full anatomy of a phone, and the patterns of connected devices.

Every Part closes with two extra pages: N.F — Every Formula, Derived, where each formula in the Part is built from scratch rather than stated, and N.P — Worked Problems, where ten to sixteen problems are solved step by step with the solutions hidden until you want them.

What is deliberately left out

Fabrication process detail, microwave engineering's boundary-value mathematics, and the heavier electromagnetic field theory. They are real subjects, but nothing in ordinary engineering life, technical conversation or curiosity depends on them, and their absence costs the rest of the volume nothing.

How this volume connects to the others

Volume I, Chapter 1.1 treated the transistor as a black box — a switch controlled by a voltage — and deliberately deferred the physics. Part 2 here is where that debt is paid: what p-type and n-type silicon are, what a depletion region is, and how a channel physically forms.

Volume II supplies the mathematics. Differential equations (Volume II, Part 6) drive the transient analysis in Part 1. Complex numbers (Volume II, 2.5) become phasors. Fourier, Laplace and convolution (Volume II, Part 9) are the entire backbone of Parts 4 to 6. You do not need to have read them — every tool is re-explained where it is used — but they are the deeper treatment if you want it.

Start here: 1.1 — Charge, Current, Voltage and Power.