‎BRAUN, FERDINAND. - THE INVENTION OF THE CATHODE-RAY INDICATOR TUBE - SEEING BY ELECTRICITY.‎
‎Ueber ein Verfahren zur Demonstration und zum Studium des zeitlichen Verlaufes variabler Ströme" (On a Method for the demonstration and study of currents varying with time).‎

‎Leipzig, Johann Ambrosius Barth, 1897. No wrappers. In ""Annalen der Physik und Chemie, Neue Folge"", Bd. 60, No 3. Pp. 401-576, textillustr. and 2 folded plates. (the entire issue offered, ""Heft 3""). Braun's paper: pp. 552-559 a. 6 textillustrations (showing the Braun tube and its operations). Clean and fine.‎

Reference : 43448

‎First printing of this groundbreaking paper being the first description of the principles governing the ""BRAUN TUBE"", which moves the elctron beams of alternating voltage, the principle on which ALL TELEVISON TUBES operate. - Braun shared the Nobel Prize for 1909 with Marconi ""in recognition of their contributions to the development of wireless telegraphy"".""Cold cathode tube with side anode, annular diaphragm to control spot size, and built-in fluorescent screen. Beam deflection by one external coil with the trace viewed indirectly in a rotating mirror, or by two coils at right angles for direct viewing. Excitation by hand-drive influence machine (friction generator) or by an induction coil. This ""indicator tube"", which enabled Braun to demonstrate how a variety of periodic and transient electrical phenomena could be visually examined, is the ancestor of electric oscilloscopes, televison picture tubes, and other electron-beam display devices.""( Shiers & Shiers ""Early Televison. A Bibliography to 1940"", No. 263).""The first oscilloscope, or Braun tube, was introduced in 1897. In order to study high-frequency alternating currents Braun used the alternating voltageto move the electron beam within the cathode tube. The trace on the face of the cathode tube represented the amplitude and frequency of the alternating-current voltage. He then produced a graph of this trace by use of a rotating mirror. The Braun tube was a valuable laboratory instrument, and modifications of it are a basic devise in electronic testing and research. The principle of the Braun tube, moving a electron beam by means of alternating voltage, is the principle on which all televison operate.""(DSB II, pp. 427-428).In 1909 he shared the Nobel Prize for physics with Guglielmo Marconi for their development of wireless telegraphy.‎