The Armstrong modulator is an indirect method of generating frequency modulation (FM). It first produces a low-deviation FM signal using a phase-modulation technique and then uses frequency multiplication and mixing stages to obtain the required carrier frequency and deviation. In contrast, direct FM generation changes the carrier frequency directly, commonly using a voltage-controlled oscillator (VCO).
Which of the following is an indirect method of generating FM?
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This question is part of 📡 Electronics and Communication Engineering (ECE) within the broader 🛠️ Engineering Essentials subject and appears in the PTS Pakistan Testing Service preparation collection. Reviewing the answer together with nearby questions helps reinforce the underlying concept and identify how it may appear in competitive exams.