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Wireless Telegraphy and Telephony Whittaker's Practical Handbooks BOUGHT WITH THE INCOME FROM THE SAGE ENDOWMENT FUND THE GIFT OF Slenrs W. Sage 1891 A^-zco^L^. imhmk *iiilIii«.&ISfi''X a"f telephony ,3 1924 031 240 olin.anx 280 (3) 4r. Elliott's Gas and Petroleum Engines, Harris'Practical Chemistry, 3 vols. 2s. 6d. Hatch's Mineralogy, 2s. 6d. Industrial Electricity, 2s. 6d. Hatton's Mathematics, 2s. 6d. Engineer Draughtsmen'sWork, is. 6d. Hawkins' and Wallis's Dynamo, i5j-. Fitting, Homer, ^s. Heat Engines, Anderson, 6s. Locomotive, McDonnell, is. Helical Gears, Homer, 5^. Engines, Model, Alexander, 6s. net. Herbert's Telegraphy, 6s. 6d. net. English and American Lathes, Telephone System of the Post Homer, 6s. Office, y. 6d. Experiments with Vacuum Tubes, Hering, Electric Railways, ^.6d. net. Salomons, 2s. Hertzian Waves and Wireless Tele- Electrical, Bonney, 2s. 6d. graphy, Bottone, y. Explosives, Manufacture of, Guttmann, Hewitt's Organic Chemical Manipula- 2 vols. 2/. 2J. tion, 4?. 6d. Farley's Cellar Book, is. 6d. Hills' Gas and Gas Fittings, 5^. net. Farman's Auto Cars, $s. Hobart's Electric Motors, 1 2^. 6(f. net. Farrow's Specifications for Building Hobart and Steven's Steam Turbine Works, 3J. 6d. net. Engineering. Stresses and Strains, 5^. net. Hobart and Turner's Insulation of Field Work and Instruments, Electric Machines, loj. 6d. net, Walmisley, 6s. net. Hobbs' Electrical Arithmetic, is. net. Findlay's Railway Working, Is. 6d. Hoblyn's Medical Dictionary, 10s. 6d. Fitting, Engineer, Homer, 5j. Homer's Helical Gears, t,s. —— Electric, Maycock, 6s. Iron-founding, 3/. 6d. Electric Light, Allsop, 5^. Lathes, 6s. Fletcher's Architectural Hygiene, 5^. Metal Turning, 3s. 6d. net. Pattern Making, y. 6d. Carpentry and Joinery, 5^. net. Principles of Fitting, 5j. —— Steam-jacket, is. 6d. 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Turner and Hobart, 10s. 6d. net. Greene s Saints and their Symbols, Iron and Steel Stmctures, Twelve- y. 6d- trees, 6s. net. Greenwell and Elsden, Road Con- Ironfounding, Homer, y. 6d. struction, S^. net. Italian Dictionary, Baretti, 2ls. Griffiths' Manures, Js. 6d. Technical Dictionary, Webber, Guttmanu's Manufacture of Explos- 4^. net. ives, 2 vols. , 2l. 2S. Jukes-Browne's Geology, 2s, 6d. Guttmann's Percentage Tables for Kapp's Electric Transmission of Analysis, y. net. Energy, \os. 6d, WIRELESS TELEGRAPHY AND TELEPHONY WHITTAKER'S PRACTICAL HANDBOOKS. BoNNEV, G. E. Induction Coils, 3s. BoTTONE, S. R. Electrical Instrument Making. 3s. 6d. „ Electric Bells. 3s. „ Electro Motors. 3s. ,, _ Galvanic Batteries. 5s. ,, Radiography and X Rays. „ Radium, is. net. „ Wireless Telegraphy. 3s. ChambeRj G. F. Astronomy, is. net. Crapper, E. H. Electrical Measurements, zs. 6d. Machines. 5s. Gray, J. Electrical Influence Herbert, T. E. Telegraphy. 6s. 6d. net. Telephone System of the British Post Office. 3s, 6d. J J Lodge, Sir O. Lightning Conductors and Lightning Guards. 155. Maycock, W. p. Alternating-Current Circuit and Motor. 4s. 6d. net. 6s. ,, Electric Wiring, Fittings, Switches and Lamps. Distribution. Vol. I. ,, Electric Lighting and Power 6s. ; Vol. II. 7S. 6d. Tables. 3s. 6d. ,, Electric Wiring Owen, W. C. Telephone Lines and Methods of Constructing Them. 5S. Poole, J. Practical Telephone Handbook. 6s. net. Webb, H. L. The Telephone Service, is. net. Whittaker's Electrical Engineers' Pocket Book, 3s. 6d. net. WHITTAKER & CO., 2 White Hart Street, London, E.G. WIRELESS TELEGRAPHY AND TELEPHONY By Prof. DOMENICO MAZZOTTO TRANSLATED FROM THE ORIGINAL ITALIAN BY s.* r.»"1bottone IVITH 253 ILLUSTRATIONS THE'rADIOTELEGRAPHIC station of ST. CATALDO (bARI) WHITTAKER & CO. 2 White Hart Street, Paternoster Square, London, E.C. AND 64 and 66 Fifth Avenue, New York • 1906 15 GLASGOW : PRINTED AT THE UNIVERSITY PRESS IJV ROBEIIT MACLEHOSE AND (JO. LTp, ; PREFACE It is with feelings of real pleasure that the translator pre- sents this work, done into English, to the English reader. Prof. Mazzotto has executed his task so thoroughly as to leave no important facts or theories connected with Radiotelegraphy unnoticed ; and has clothed his thoughts in language at once so simple, so clear, and so forcible, as to render the comprehension of the subject easy to the merest tyro. The writer feels that some of the beauty of the style must inevitably have been lost in translation but he trusts that he has been able to keep as nearly to the original as the difference, of idiom would allow. S. BOTTONE. Wallington, 1906. — CONTENTS PAGE Introduction, x Chapter I. General Notions on Wireless Communications, 1-7 Chapter II. Wireless Telegraphy by Conduction, 8-21 Transmission across Water—Morse and Lindsay's Experi- ments—Smith's, Highton's, Barbouse and Rathenaii, and Rubens' Systems—Communications through Ground Steinheil and Michel Systems— Strecker, Orhng, and Armstrong's Experiments—Maiche's System. Chapter III. Wireless Telegraphy by Induction, 22-42 Applications of Electro-static Induction—Applications of Electro-dynamic Induction—Electro-static and Smith and Edison's System—Dolbear's System—Other forms of Edison's System— Kitsee's, Tesla, Electro-dynamic, Trow- bridge, Phelps and Woods-Adler and Eversted-Lennet Systems—Preece's Experiments—Syntonised System of Lodge. Chapter IV. Radiophonic System, 43-54 Experiments and Applications—Bell-Tainter Radiophone Mercadier Radiophone—Simon and Reich's Radiotele- phone—Ruhmer's Radiophotophone—Clausen and van Bronck's Radiophone. — CONTENTS vli Chapter V. page Ultra-Violet and Infra-Red Radiation Systems, S5-64 Zickler's Apparatus— Sella's and Dussaud's Systems. Chapter VI. Wireless Telegraphy by Electric Waves, 6S-9S Production of Electric Waves— Herz, Marconi's and.Lecher's Oscillators—Propagation of Electric Waves—The Recep- tion of Electric Waves—Syntony and Damping—The Influence of Daylight, Chapter VII. Radio-Telegraphic Apparatus, - 96-215 Sources of Energy—Keyboards—Automatic Transmitters Coils and Contact Breakers—Ruhmkorff Coil— Unipolar Transformer—Dry Contact Breaker—Foucault, Lodge- Muirhead, Rotary or Turbine, Wehnelt, 'and Cooper- Hewitt Breaks— Converters—Exciters and Oscillators— Righi- Marconi and Tissot's Oscillators —Ruhmkorff, Arm- strong-Orling, Slaby-Arco, and Fessenden Exciters Antennae Radiators and Sky Rods— PopofiF Antennae, Radiators, and Sky Rods—Popoff Antenna—Marconi Sky Rod—Multiple Sky Rods—Aerial Pavilions— Ultra- powerful Radiators—Antennae and Concentric Cylinders — Antennae for Directed Waves — Artom Radiator —Magni's System—Radiators without Antennae —Con- nections to Earth — Transiormers — Marconi - Kennedy Receiving Transformers — Marconi's Transformer for Sending Apparatus— Braun's, Tesla, and Oudin and d'Arsonval Transformers—Braun Condensers—Slaby-Arco Condenser—Condenser at Poldhu—Syntonisers— Portable Syntonising Coil—Doenitz Wave Measurer—Wave De- tector —The Coherer—History of the Discovery—Theory —Practical Notions—Types—Ordinary Coherers with Filings—Lodge's, Marconi, Slaby, Blondel, Ferrie, Ducretet's, Rochefort's, Magnetic, Tissot's, Braun's, Simple Contact, Orling and Braunerhjelm's, Popoff-Ducretet's, and Branly Coherers—Mechanical and Magnetic Deco- herers—Coherers with Spontaneous Decoherers—Hughes', Tommasina Telephonic, Popoff, "Italian Navy," Lodge's — viil CONTENTS PAGE Self, and Dorman Coherers—Anti-Coherers—Schaeffer's Plate—De Forest's and Smithe's Responder— Rutherford, Wilson, Marconi, Tissot's, Ewing-Walter, and Arno Detectors — Fessenden's Thermic Revealer ^ Walton, Armorl's, and Placher's Revealers—Sensibility of Re- vealers—Relays—Polarised Relays—Movable Coil Relay —Other Types—Hughes Printer— Other Printing Re- ceivers ^Lodge-Muirhead Recorder — Repeaters — Cole- Cohen, Guarini, Armorl Systems. Chapter VIII. On the Various Systems of Radio-Telegraphy, 216-307 Generalities^The Marconi Systems—Apparatus with Re- flectors—With Radiating Laminae—Connected to Earth With Antennae—Double Stations—Receivers in which the Antennae are Insulated from the Coherer—Syntonic Apparatus having Concentric Cylinders-^Portable Stations —Ultra-powerful Apparatus—Arrangement of the Ap- paratus—Sending Station—Receiving Station—Syntonic Induction—Electric Wave Syntonic and Lodge-Muirhead New Apparatus—Apparatus for Military Use—Braun's Systems—Transmissions through Water—Principles of his Method— Apparatus Requisite—Practical T;xperiments —Aerial Transmission—Fundamental Innovations— Prin- cipal, System—Other Modifications— Practical Arrange- ments—Radio-Telegraphic Apparatus for Field Work Parabolic Radiator System—Slaby-Arco System—Prin- ciples of the System—Syntonised Systems—Transmitting and Receiving Apparatus—Popoif-Ducretet, Fessenden, De Forest's, and various
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