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Limits RegistryBritish engineer Alec Reeves, working for International Telephone and Telegraph in Paris, conceived pulse-code modulation for voice communication in 1937 and filed a French patent in 1938. PCM, the basis of digital telephony, the compact disc and almost all digital audio, saw little use until transistors made it practical decades later.
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British engineer Alec Reeves, working for International Telephone and Telegraph in Paris, conceived pulse-code modulation for voice communication in 1937 and filed a French patent in 1938. PCM, the basis of digital telephony, the compact disc and almost all digital audio, saw little use until transistors made it practical decades later.
The year Alec Reeves conceived pulse-code modulation — sampling, quantizing and binary-coding a speech waveform — for telephony.
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Limits Registry. LR-FIRST-PCM-VOICE-CONCEPT. Conception of pulse-code modulation for voice. 2026.