Biographical Notes

HARLOW 14th December, 1964.
last item added later

Biographical Information, etc. on A.H. Reeves

1902Born in Redhill, Surrey (near London). Son of E.A. Reeves, Chief Technical Officer of the Royal Geographical Society, London.
1910''Radnor'' Preparatory School, Redhill.
1914 Reigate Grammar School, Surrey, where he matriculated in 1917.
1918 Governors' Scholarship to City and Guild's Engineering College, London (Imperial College of Science, now part of London University).
1921 to
Obtained ACGI (= BSc. Engineering). Further work at Imperial College, leading to the post-graduate to qualification of DIC. Original work, mostly mathematical, on the RF impedance of co-axial ferromagnetic condensers, and experimental studies on applications of phase locking between sine-wave oscillators with non-linear parameters, and on improved cathode-ray tube designs. Invented Cathode Ray tube Radio Direction findings (CRDF)1.
1923 to
Joined Laboratories of London branch of International Western to Electric Co. (which later became Standard Telephones and Cables Ltd., part of ITT). Worked on the original transatlantic radiotelephone systems; also on precision radio-frequency measurements2, and on low-noise broadcast microphones3. In 1926 invented and used the multi-stage aperiodic binary counter, based on an improved version of the original Eccles-Jordan ciruit4.
1928 Joined Paris Laboratory of ITT, at its foundation.
1929During the experimental and early stages, in technical charge of the first (short-wave) radio link connecting the-commercial telephone systems of Spain and S. America.
1930Developed the first single-sideband high-frequency radio telephone system5. Invented electronic Automatic Frequency Control (AFC) - (for re-supplying the carrier frequency at the receiver6). Invented and demonstrated in principle the circulating delay-line store for digital information.
1931Pioneer work on multiplex telephony by Pulse Amplitude Modulation (PAM)7.
1932Made a prototype of the first superheterodyne receiver for microwaves (about 2000 Mcs.), using AFC for controlling the local oscillator8.
1933Pioneered a simple multi-channel carrier system for UHF radiotelephone links (developed and used later on the first VHF link connecting the commercial telephone systems of Gt. Britain and Ireland).
1934Experimental work on an early radar method, for an airborne altimeter.
1935Basic circuit design of the first USW radiotelephone link connecting Spain and the Balearic Islands. In technical charge during the experimental and early operational stages.
1936 to
Invented and carried out experimental work on the Pulse Time Modulation (PTM, or PPM) systems, to reduce noise on telephone or radiotelephone links9. Invented Pulse Code Modulation (PCM), mainly to prevent cumulative noise on long telephone or radiotelephone circuits10
1940Until the French-German armistice, worked at the ITT Paris Laboratories on radar for the French Air Force, in co-operation with the British Air Ministry. Then continued the radar work for the Royal Air Force, first at the Royal Aircraft Establishment, and later as a Principal Scientific Officer at the Air Ministry Research Establishment founded by Watson Watt, then at Swanage, Dorset.
1940 to
At various periods responsible at AMRE (now TRE for experimental work and design for the Royal Air Force of their radio countermeasures systems ("beam-bending", etc.), radar Ground Controlled fighter Interception (GCI), operational research, and the "Gee" guidance system. With F.E. Jones, invented the "Oboe" system (for accurate bombing through overcast), used later for large-scale raids by the RAF, and by the USAF 8th and 9th Bomber Groups. Held design responsibility far Oboe equipment. In 1945 made an Officer of the Order of the British Empire, far his war work.
1945 Joined Standard Telecommunication Laboratories, Ltd., London, the main British Laboratories of ITT, in charge of a Division. Worked an early electronic switching methods. In search of relevant better devices, invented and worked en the multi-point cold-cathode gas counter tube11
1946 to
Invented the "residual ionisation" method of stabilising triggering potentials in pulse cold-cathode gas tubes. Developed a prototype multi-point gas tube for pulse electronic switching and pulse-time modulating. Invented a number of cold-cathode pulsed gas tubes far special applications13.
1948 to
Worked on early point-contact transistors, especially on pulse "forming" techniques. With R.B. Cooke, invented the "positive gap" germanium diode, a fast device having a PNPN-type characteristic13.
1950 to
Responsible at STL for co-ordination work, and executive supervision of various component and circuitry teams, working partly on classified projects.
1961 to 1969Returned to active laboratory work, mainly on improved methods and devices for PCM. Invented the "equilibrium" method of data processing and started applying it to solid-state PCM coders14. Head of the exploratory circuit research area of STL.
1969 to 1971Worked from home for the British Post Office on Pulse Position Code Modulation for optical repeaters, which work was not complete upon his death. The study was completed by Charles Cecil Eaglesfield in 1972.

He was a Member of the (British) Institution of Electrical Engineers.


1Article in Popular Wireless, 1922.
2British Patent 296,827.
3A Solution of the Problem of the Broadcast Microphone. Electrical Communication, Vol- 7, No. 4, April 1929.
4British Patent 321,682.
5 The Single Sideband System Applied to Short Wave Radio Links. Journal of the Institution cf Electrical Engineers (Britain), Vol. 73, 1933.
6 Ref. (5), p. 266.
7French Patent 837,921 filed Oct. 30th 1937 (six years after the experimental studies).
8 Published five years later.Superheterodyne Reception of MicroRays. A.H. Reeves and E.H. Utlrich. Electrical Communication, vol. 16, No. 2, Oct. 1937-
9 French Patent 833,929 filed June 18th 1937. French Patent 49.159/833 filed July 5th 1937.
10French Patent 852,153 filed Oct. 3rd 1938 (and others).
11British Patent 639,827.
12 British Patent 665,818 and forty-three others.
13Germanium Positive Gap Diode: New Tool for Pulse Techniques. A.H. Reeves and R.B. Cooke, Electrical Communication, Vol- 32, June 1955.
14British Patent 20642/63 British Patent 37714/63 (with K.W. Cattermcle 7nd R. Kitajewski). Also, Voice-operated Level Control System for Telephone Networks. Electrical Communication, Vol. 17, No. 3, Jan. 1939.