Book excerpt: 110 Waveform Generator Projects for the Home Constructor deals with waveform generator circuits that can produce forms of sine, square, triangle, sawtooth, ramp, pulse, or staircase. The generator circuits, built by the constructor using transistors, operational amplifiers or digital integrated circuits, can produce modulated or unmodulated outputs, with single or multiple form outputs. The constructor must follow two requirements in building a simple sine-wave oscillator: firstly, the output of an amplifying device must be fed back to its input via a frequency-selective network in such a way that the sum of the amplifier and feedback network phase-shifts equals zero (or 360) degrees at the desired oscillation frequency. Secondly, the gain of the amplifying device must exactly counter the loss or attenuation of the frequency-selective feedback network at the desired oscillation frequency, to give an overall system gain of precise unity. The book also describes different waveform modulations, such as amplitude modulation (a.m.), frequency modulation (f.m.), frequency-shift keying (f.s.k.), phase-shift keying (p.s.k.), sweep modulation, carrier keying, and how to apply these in practical circuits. Radio technicians, engineers, apprentices, hobbyists, and students of electrical engineering or electronics will find the book very useful.