Alec Harley Reeves was born on 10 March 1902 , in Redhill, Surrey, England.
His father, Edward was Surveyor to the Royal Geographical Society and had met Livingstone, Stanley and Gordon of Khartoum. Edward used his mapping skills in an effort to resolve the bitter battle between American explorers Robert Peary and Frederick Cook, who both claimed they were the first to reach the North Pole. I have been unable to find out anything about Alecs' mother.
Alec was educated at the Radnor Prepartory school in Rdehill, then went to Reigate Grammar School, where he matriculated in 1917, then, aged 16, he was admitted under a Governors' Scholarship to the City & Guilds Engineering College London (Imperial College of Science, now part of London University) in 1918. In 1921 he attained its ACGI qualification (equivalent level to BSc) and then did postgraduate studies at the Imperial College of Science and Technology (London), his post graduate research on a cathode ray direction finding system lead to his receiving his Diploma of the Imperial College (DIC) in 1922 or 1923 (sources vague about the actual date).
In 1923 Alec joined International Western Electric (the manufacturing arm of American Telephone & Telegraph), a leading manufacturer of radio and telecommunications equipment. In 1925 Western Electrics' European operations were acquired by International Telephone and Telegraph (ITT). In 1926 Alec invented a multi-stage aperiodic binary counter (cascaded flip-flop counter).
In 1927 Alec went to work at LMT, the ITT laboratory in Paris. While there he and his colleagues built the first radio-telephone links across the English Channel and the Atlantic and developed a multi-channel carrier system for UHF radio telephones. Alec also perfected the condenser microphone and made major advances in the use of SSB (single sideband) transmission for short-wave radio, invented electronic Automatic Frequency Control (AFC), invented and demonstrated in principle the circulating delay-line store for digital information and much more! He seemed to have enjoyed his time in Paris, he even claimed he had played in the French Open Tennis Championships, which were, indeed, 'open' to anyone who wished to participate!
Alec had recognised the potential that Pulse-Code Modulation (PCM) had for reducing noise when speech is transmitted over long distances (PCM is a digital representation of an analog signalling where the magnitude of the signal is sampling regularly at uniform intervals, then Quantization (approximating the continuous signal) to a series of symbols in a numeric code). With an analogue signal every time the signal is amplified, the noise contained in the signal is also amplified. With PCM, all that is required is to regenerate the pulses, hence the noise content of the signal is not increased. Alec patented the invention in 1938 but, unfortunately, his idea required quite complex circuitry (by 1930s standards), and was not cost effective using Thermonic Valves (Tubes). Pulse-Code Modulation was not used commercially until the 1950s, when the invention of the transistor had made it viable, although it was used by Bell Telephone Laboratories during the Second World War for secure though complex, communications links, such as the one between Franklin D. Roosevelt and Winston Churchill.
Following the invasion of France in 1940 by Germany, Alec managed to escape over the Spanish border and made his way back to England aboard a cargo ship (a coal boat). He joined the Royal Aircraft Establishment at Farnborough as, though he was a pacifist, he saw the need to defeat Hitler and took part in the development of countermeasures against the German radio navigation systems, the so called 'Battle of the Beams'. Alec was later transferred to the Telecommunications Research Establishment as part of a team of scientists and engineers developing Britains' own Radio Navigation aids. The first system they developed was called 'GEE', the system performed well, but was susceptible to jamming and was not accurate enough for blind bombing of targets at night or in thick cloud. Alec went on to develop a new system called 'Oboe', which offered pin-point accuracy to within 50 yds (45m), and was resistant to jamming. 'Oboe' was to prove invaluable to the Royal Air Force during Bomber Commands' offensive against Germany, in fact nothing as accurate as the Oboe system would exist until the days of the satellite and the laser!
In 1945 he returned to ITT and researched ways to increase the capacity and reliability of communications systems. He was a pioneer of semiconductor devices and among the first to exploit the possibility of using light to carry information. In the late 1960s Alec inspired and led the team under Charles Kao and George Hockham that created the worlds' first practical optical fibre system.
Alec was a visionary who predicted, in the 1950s, that by the end of the 20th Century people would work from home, linked by optical fibre and receiving information over a screen (see: History of Computing Part 2: 1943 to 1971 for how "advanced" computers were in the 1950s).
Alec died on 13 October 1971, still working but by now from home, for the British Post Office on Pulse Position Code Modulation for optical repeaters. The work was not complete upon his death but the study was completed by Charles Cecil Eaglesfield the following year.
Alec had held over 100 patents in his name and contributed to many important technologies, but there's little doubt that PCM had the greatest impact of all. Without PCM there would be no Internet, no digital radio or television, no digital land-line or mobile telephones, no CDs, DVDs, CD-ROMs or Blu-ray discs. Indeed, the very idea of sending information in any form, anywhere at any time, would still be the stuff of science fiction. It's little wonder that Alec Harley Reeves CBE is known as the Father of the Information Age.