| Solar System |
Pythagoras |
500 BC |
| Golden year [nineteen-year
astronomical cycle] |
Meton |
432 BC |
| Helio-centric [sun centered]
universe |
AristArchus [then
Copernicus] |
Respectively 350BC then
1543 AD |
| Speaking Trumpet |
Alexander the Great |
335 BC |
| Oldest written description
of data transmission system [alphabet characters represented by code
of up to five torch positions on two walls] |
Polybius |
300BC |
| Length of tropical year
[accuracy 12 seconds] |
HippArchus |
145BC |
| Julian Calendar [prepared
for Julius Ceasar] |
Sosigenes |
45BC |
| Decimal notation |
India |
900 |
| Magnetic compass [used 24
points, reckoned from south] |
China |
12th century |
| Rockets in warfare |
China |
1232 |
| Decimal notation introduced
to Britain |
- |
1253 |
| Difference between
geographic and magnetic north pole |
Columbus |
1492 |
| Helio-centric [sun
centered] universe |
Copernicus [after
AristArchus] |
1543 |
| Mercator's map projection
[Latinised form of name] |
Kremer |
1560 |
| Calendar reform [not
adopted by England until 1752] |
Gregory |
1582 |
| Static electric forces
described |
Gilbert |
1600 |
| Telescope |
Galileo |
1608 |
| First law - elliptical
orbit |
Kepler |
1609 |
| Second law - constant
angular momentum [i.e., equal swept areas in orbital plane in equal
time periods] |
Kepler |
1609 |
| Third law - [orbital
period]²
∞ [semi-major axis]³ |
Kepler |
1618 |
| Calculating machine |
Pascal |
1642 |
| Law of universal
gravitation |
Newton |
1666 |
| Semaphore with telescope |
Hooke |
1684 |
| First law - inertia
[Galileo's law of inertia]. Second law - force, mass and
acceleration. Third law - direct reaction |
Newton |
1687 |
| Possibility of artificial
earth satellite |
Newton |
1687 |
| Insulated electrical lines |
von Guericke |
1720 |
| Marine chronometer |
Lloyd |
1735 |
| Gyroscope |
Setson |
1744 |
| Capacitor [known as Leyden
phial or jar] |
Musschenbroek |
1746 |
| Electric conduction |
Grey |
1720 |
| Electricity propagated by
wire [3km] |
Watson |
1747 |
| Gregorian calendar adopted
by England |
- |
1752 |
| Static electric telegraph
[24 lines to 24 pitch-ball electrometres] |
Lesage |
1774 |
| Single line static electric
telegraph |
Lomond |
1787 |
| Pulse position modulation
[timed sparks at end of line] |
Chappe |
1790 |
| Semaphore with mechanical
arms |
Chappe |
1794 |
| Six shutter optical
telegraph |
Murray |
1795 |
| Gravitational constant, G |
Cavendish |
1797 |
| Electrolysis |
Pearson |
1797 |
| Negative numbers |
India |
1797 |
| Primary electric cell
[silver zinc] |
Volta |
1800 |
| Cloud formation
classification |
Howard |
1803 |
| Arc light |
Davy |
1808 |
| Electro chemical telegraph
[decomposed water - one line and electrode per character] |
Soemmering |
1809 |
| Mechanical computing
"engine" |
Babbage |
1812 |
| Electro magnetism |
Oersted |
1819 |
| Light as "waves" |
Fresnel |
1820 |
| Magnetisation of soft iron |
Arago and Faraday |
1820 |
| Multi turn coil as electro
magnet "multiplier" |
Schweigger |
1820 |
| Magnetised needle telegraph
[one needle per character] |
Ampre |
1820 |
| Single magnetic needle
telegraph [coded characters -up to four serial digits per character] |
Schiling |
1825 |
| Transformer [induction
coil] |
Faraday |
1831 |
| Commercial electric
telegraph |
Gauss and Weber |
1833 |
| Rectifier - asymmetric
electric conduction |
Munk |
1834 |
| Refrigeration |
Perkins |
1834 |
| Five needle parallel coded
telegraph |
Wheatstone and Cooke |
1837 |
| Telegraph using signal
relay at distant end to key fresh power source |
Davy |
1838 |
| HF oscillations observed at
a distance |
Henry |
1840 |
| Frequency effects of
relative motion [light from stars] |
Doeppler |
1843 |
| Electromagnetic telegraph |
Morse and Vail |
1844 |
| Incandescent lamp [carbon
in vacuum] |
Starr |
1845 |
| Telegraph printing roman
characters instead of code |
House |
1846 |
| Automatic telegraph
transmitter |
Bain and Wheatstone |
1846 |
| Gutta percha for submarine
cables |
Faraday |
1849 |
| Submarine telegraph cable
[Connecticut River] |
- |
1849 |
| Speaking tube |
Wishaw |
1850 |
| Submarine telegraph single
wire cable Dover to Calais [operated only one day] |
Brett |
1850 |
| Submarine telegraph cable
Dover to Calais [permanent - four, separated insulated wires] |
- |
1851 |
| Fundamental system of
electrical and magnetic measurements |
Weber |
1851 |
| Duplex telegraphy |
Gintl |
1853 |
| Microphone |
Bourseul |
1854 |
| Transient response of a
transmission line |
Kelvin |
1855 |
| Electric lighthouse
illumination [South Foreland] - Arc with clockwork spacing control |
Foucault-Dubosq |
1858 |
| Telegraph polarised relay |
Siemens |
1858 |
| Submarine telegraph,
Ireland to USA 2630 km [initial cable only lasted for 700 messages] |
Field |
1858 |
| Rubber insulation for
cables |
Hooper |
1859 |
| Submarine telegraph,
transatlantic permanent [25 words per minute Morse code] |
- |
1866 |
| Angstrom unit of length |
Angstroem |
1868 |
| Gyro stabiliser |
Watt - Boulton |
1868 |
| Navigational satellite
proposal [a novel] |
Hale |
1869 |
| British telegraph
installations taken over by Post Office |
- |
1870 |
| Multiplex telegraphy
[f.d.m.] - morse code, mechanical resonance |
Bell |
1870/1874 |
| Telephone |
Bell |
1872 |
| 500 b/s data transmission
system |
Edison |
1874 |
| Vacuum carbon filament
dockyard lamps |
Lodyguine |
1874 |
| First parallel connection
of electric lamps [42 Arcs] |
Farmer |
1875 |
| Multiplex telegraphy
[t.d.m.] five unit code |
Baudot |
1875 |
| Sidebands demonstrated in
acoustics |
Mayer |
1875 |
| Electro magnetic microphone
- moving iron |
Bell |
1876 |
| Carbon microphone |
Edison |
1877 |
| Dynamic microphone - moving
coil |
Cuttris USA. Siemens
Germany, then Wente |
1877
1931 |
| Magneto telephone exchange
with drop indicators [New Haven Connecticut] |
Jones |
1878 |
| Laser |
Bell and Tainer
then Townes and Schawlow |
1878
1958 |
| First telephone exchange
switchboard in Britain |
- |
1879 |
| Piezo-electric effect |
Curie |
1880 |
| Condenser microphone |
Dolbear
then Wente |
1881
1917 |
| Thermionic emission |
Edison |
1883 |
| Spark transmitter |
Hertz |
1886 |
| Frequency division
multiplex speech using mechanical resonance |
Leblanc |
1886 |
| Parametric oscillation |
Rayleigh |
1887 |
| Wireless telegraph [morse
code] |
Lodge |
1887 |
| Equalised line |
Heaviside |
1887 |
| Radar |
Hertz
then Watson-Watt] |
1888
1937 |
| Ratchet-and-pawl telephone
selector |
Strowger |
1889 |
| Metallic valve filaments
[platinum] |
Fleming |
1890 |
| Submarine four core
telephone cable Dover to Calais |
- |
1891 |
| Standard primary cell -
mercury-cadmium |
Weston |
1892 |
| Electrical resonance and
f.d.m. telephone system |
Autin and Leblance |
1892 |
| Coherer detector |
Branley |
1892 |
| Revised five unit telegraph
alphabet [now called ITA No 2. |
Murray |
1895 |
| Cathode ray tube |
Crookes |
1895 |
| X-rays [discovered from
c.r.t. experiments] |
Roentgen |
1895 |
| Wireless telegraphy ship to
ship |
Jackson |
1895 |
| Commercial common-battery
telephone exchange - Worcester Massachusetts |
- |
1896 |
| Automatic telephone
exchange Augusta New York |
- |
1896 |
| Quarter wave antenna |
MArconi |
1896 |
| Frequency tuning [called
syntonic wireless] |
Lodge |
1897 |
| Rectifier as a.m. detector |
Pupin |
1898 |
| Coupling circuits |
Braun |
1898 |
| Radio controlled model boat |
Tesla |
1898 |
| Wireless telegraphy across
English Channel |
MArconi |
1899 |
| Thermionic emission
consisting of electrons |
Thomson |
1899 |
| Magnetic tape recording |
Poulsen |
1899 |
| Telephone line repeaters |
Lyons |
1900 |
| Radio telephony [2km with
10 kHz rotary spark gap] |
Fessenden |
1900 |
| Amplitude modulated radio |
Fessenden |
1901 |
| Wireless telegraphy
Cornwall to Newfoundland |
[Receiver at St
John-Marconi transmitter at Poldhu-Fleming] |
1901 |
| British telephone systems
taken over by Post Office |
- |
1901/2 |
| Loaded transmission line
[New York to Newark New Jersey] |
Pupin |
1902 |
| Upper atmosphere reflection
of radio |
Heaviside |
1902 |
| Frequency modulation |
Ehret
then Armstrong |
1902
1924 |
| Multi stage rocket theory
defined |
Tsiolkovsky |
1903 |
| Time division multiplex
speech |
Miner |
1903 |
| Arc transmitter with
frequency shift keying [f.s.k.] |
Poulsen |
1903 |
| Two electrode vacuum tube
rectifier |
Fleming |
1904 |
| Directional antennae |
MArconi |
1905 |
| Quenched spark transmitter |
Wien |
1906 |
| C.W. Oscillations |
Poulsen |
1906 |
| 320 km radio telephony |
Fessenden |
1906 |
| High frequency alternators |
Alexanderson |
1907 |
| Triode amplifier valve
[called "audion"] |
de Forest |
1907 |
| Cathode ray oscillograph |
Ryan |
1911 |
| Crystal microphone [led to
ASDIC] |
Langevin |
1914-1918 |
| Transatlantic radio
telephony Arlington to Paris [transmitter with many paralleled
triodes] |
[USA] |
1915 |
| Sidebands in electrical
communications |
Carson |
1915 |
| Filters |
Campbell |
1915 |
| Modulo-2 addition circuits
[used for message encryption] |
[Great Britain] |
1915 |
| Telephone New York - San
Francisco [5200km over open wires] |
- |
1915 |
| Maser |
Einstein
then Gordon, Zerger and Thomas |
1917
1954 |
| 'Relay' automatic exchange
telephone co-ordinate selector |
Betulander |
1917 |
| Condenser microphone |
Wente |
1917 |
| FM infinite sidebands and
'Carson's Rule' |
Carson |
1922 |
| Ribbon microphone principle |
Schottky
then Olsen |
1923
1931 |
| FM practical development |
Armstrong
after Ehret |
1924
1902 |
| Radio facsimile cheque
London to New York |
Ranger |
1923 |
| Commercial radio facsimile
transatlantic |
- |
1926 |
| Tetrode [S625 valve] |
Round |
1926 |
| Liquid propellant rocket |
Goddard |
1926 |
| Mu-metal used for loading
submarine cables [telegraph speed 2500 word per minute instead of
25] |
- |
1926 |
| Rugby [UK] HF transmitter |
- |
1927 |
| 12 channel f.d.m. 400
word/min telegraph on single line pair [Western Electric] |
[USA] |
1929 |
| Superhet receiver |
Armstrong |
1930 |
| Improved dynamic [moving
coil] microphone |
Wente |
1931 |
| Improved ribbon microphone |
Olsen |
1931 |
| Underground telephone
cables in Britain |
- |
1931 |
| Radio telescope |
Jansky |
1931 |
| Microwave [20cm] telephone
link Dover to Calais [56km] |
- |
1931 |
| Cosmic noise discovered |
Jansky |
1932 |
| FM 104km New York to
Westhampton on 41 Mhz |
Armstrong |
1933 |
| FM feedback demodulator |
Chaffee |
1933 |
| Experimental crossbar
telephone exchange Ericsson |
[Sweden] |
1933 |
| Klystron |
Varian |
1934 |
| Negative feedback amplifier
[called inverse feedback |
Black |
1934 |
| Coaxial telephone cable
London - Birmingham [4 core, 280 circuit, 0.5 to 2.1 MHz, repeaters
every 8 miles] |
- |
1937 |
| Parabolic antenna |
Reber |
1937 |
| Pulse code modulation |
Reeves |
1937 |
| Radar |
Watson-Watt |
1937 |
| Gas discharge lamp |
- |
1938 |
| Crossbar telephone exchange
Bell laboratories |
[USA] |
1938 |
| I am born in July [future
user of little sparks] |
Harry and Dorothy [my
parents] |
1938 |
| FSK data link for picture
transmission [AntArctic] |
Byrd |
1939 |
| Analogue vocoder |
Dudley |
1939 |
| Bell complex-number
computer model 1 |
Stibitz |
1940 |
| Submerged repeater
[Holyhead and Isle of Man] |
- |
1943 |
| Havard Mk1 electronic
computer [used 3304 electromagnetic relays] |
Lake |
1944 |
| Multi stage combat rocket
[Rheinbote] |
[Germany] |
1944 |
| Delta modulation |
Deloraine |
1945 |
| Synchronous global
communication satellite system proposal |
Clarke |
1945 |
| Travelling wave tube |
Kompfner |
1945 |
| Atomic clock |
Libby |
1946 |
| Moon bounce communications |
[USA] |
1946 |
| Printed wiring component
board |
Sargrove |
1947 |
| Transistor |
Shockley |
1948 |
| Experimental p.c.m. link of
normal telephone quality |
Meacham and Peterson |
1948 |
| Companding suggested for
p.c.m. links |
Reiling |
1948 |
| Bell tropospheric scatter
communications ' beyond the horizon' |
[USA] |
1952 |
| Backward-wave-oscillator or
cArcinotron |
[France] |
1952 |
| Cyclic binary code [e.g.,
for shaft encoders] |
Gray |
1953 |
| Maser |
Gordon Zerger and Townes |
1954 |
| Low altitude passive
communication satellite proposal |
Pierce |
1955 |
| Transatlantic telephone
cable TAT1 Oban, Scotland to Clarenville Newfoundland 51 repeaters
144 Mhz [ 2 separate single core cables - one go and one return-
providing 35 duplex 4khz telephone circuits plus 1 telegraph
channel] |
- |
1956 |
| Tunnel diode |
Esaki |
1957 |
| Low noise microwave
amplifier [synthetic ruby maser cooled to 2 Kelvins] |
Bloembergen |
1957 |
| Artificial earth satellite
SPUTNIK 1 [84kg, perigee 230km, apogee 950km] |
[USSR] |
1957 |
| Laser [known then as
'optical maser' |
Townes and Schawlow |
1958 |
| Store-and-forward
communications satellite SCORE [3969kg, taped voice and teletype] |
[USA] |
1958 |
| VHF ship to shore public
radio telephone in Britain |
- |
1958 |
| Transatlantic moon bounce
communication, Joddrell Bank [with 33m diameter dish 200 Mhz at 1
kW] |
[UK] |
1959 |
| Inflated passive
communications satellite ECHO 1 [68kg, perigee 1400km, apogee
1800km] |
[USA] |
1960 |
| Active, delayed-repeater
communications satellite COURIER [227kg, perigee 970km, apogee
1240km, provided 16 duplex high speed teletype circuits] |
[USA] |
1960 |
| Navigation satellite
TRANSIT 1B |
[USA] |
1960 |
| WOSTOCK manned satellite
[4115kg, perigee 175km, apogee 302km] |
Gagarin [USSR] |
1961 |
| Spin-stabilised
communication satellite TELESTAR for experimental television |
[USA] |
1962 |
| Duplex 12-circuit NASA
satellite communication telephone experiment RELAY [with redundant
transponders] |
[USA] |
1962 |
| Synchronous communications
satellite SYNCOM |
[USA] |
1963 |
| Commercial geostationary
communications satellite EARLY BIRD [INTELSAT 1] [240 telephone
channels, or 1 TV channel via 2 single-access transponders] |
[USA] |
1965 |
| INTELSAT II [240 telephone
circuits or 1 TV channel via 1 multiple access transponder] |
[USA] |
1969 |
| Military geostationary
communications satellite SKYNET [launch USA] |
[UK] |
1969 |