Textbook in PDF format Build Your Own Software-Defined Radio combines RF circuitry with hardware programming and PC-based signal processing. The e-book presents a modular approach to building a complete SDR system using RF Bricks – from the mechanical framework and RF modules to measurement tools, PC software, and FPGA implementations. Practical explanations guide readers through real signal paths, construction steps, and measurement routines, linking hardware and software into a flexible SDR platform. Key topics include Mechanical setup: RF Brick template, chassis, and 19-inch module carrier Bridges: USB isolator, I²C level shifter, I²C power switch, and practical examples Signal-chain design with RF Bricks: antennas, band filters, NanoVNA work, preamplifiers, PLLs, demodulators, direct-conversion chains, multiband options, and narrowband bricks RF measurement Bricks: single- and dual-tone sources, NPR methods, noise generators, notch filters, broadband amplifiers, and impedance bridges Useful accessories: ATU-100 tuner, X-Phase QRM eliminator, and firmware notes PC host software: SoapyAudio adjustments, GQRX, SDR++, and added functionality GnuRadio elements: control blocks, SSB demodulation, GUI components, messaging, and filter handling FPGA-based SDR: VHDL, toolchains, ADC/DAC blocks, oversampling, and a complete SSB/CW signal chain With its modular structure and detailed working examples, this e-book offers a practical path to building and extending modern SDR systems