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Signor Marconi's Magic Box: The Most Remarkable Invention of the 19th ...
Limited preview - 2003
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Accordingly adjusted alternating current ammeter antenna circuit antenna current audio audion charge conductor connected coupling crystal detector cuit current flowing current thru cycle damped wave damping decrement deionization detector detuning dielectric direct current discharge earth electric electrodes energy equation filament formula gap circuit grid ground harmonics heat high resistance ignition impulse increased induction coil inserted insulated ionization ions lines of force loading coil logarithmic loop magnetic field Marconi Marconi Company maximum metal mitter negative noted in paragraph number of turns obtained ohms operation oscillating circuit oscillations passed thru pendulum plate current position Poulsen arc quenched gap radiation radio frequency reduced resonance curve result secondary circuit shown in Fig signals spark gap static swings tank circuit Telefunken telephone receivers tenna termed tion trans transformer transmitter tuning type of antenna type of gap undamped variable condenser vibration voltage wattmeter wave length wave meter wave train wire
Page 3 - Color — then — as we detect it by the eye, is merely a distinction between light waves of different length. Waves striking the retina of the eye at different rates of vibration cause different vibrations or impressions on the retina to be recorded, and these different impressions we call color. 6. The color red, we have seen, has a longer wave length than the color yellow. The colors of the rainbow, red, orange, yellow, green, blue and violet range successively in wave length from about 750 millionths...
Page 54 - ... polished and protected from ultra-violet light so as to supply the electric charge in as sudden a manner as possible. As charged surfaces or capacity areas, spheres or square plates or any other metal surfaces may be employed, but I prefer, for the purpose of combining low resistance with great electrostatic capacity, cones or triangles or other such diverging surfaces, with the vertices adjoining and their larger...
Page 28 - ... they gradually come to rest. Sonorous bodies, such as string under tension, and confined portions of air, as in the organ pipe, are further illustrations suggested by the term. Just as very feeble impulses applied to a pendulum at rest, at intervals exactly corresponding to its natural period of vibration, will cause almost any desired amplitude of swing, so bodies capable of executing vibrations by virtue of their own resiliency may be put into strong vibration by a series of impulses in tune...
Page 248 - The frequency of the beats is equal to the difference between the frequencies of the two oscillating currents.
Page 35 - Current, Forced Alternating: A current, the frequency and damping of which are equal to the frequency and damping of the exciting electromotive force.
Page 16 - E is the EMF in volts, n is the number of turns in the coil, and N is the number of lines of force cut in / seconds.
Page 80 - Thus we say, the potential of the secondary is to the potential of the primary as the number of turns in the secondary is to the number of turns in the primary.
Page 28 - As any circuit possessing inductance and capacity tends to oscillate electrically at its own frequency, it becomes the seat of an induced oscillatory current when subjected to the influence of electric waves of that frequency, each wave giving a slight impulse to the readily excited oscillations, with the result that the induced electromotive forces will be amplified in intensity, just as the swing of a pendulum is amplified by the application of properly timed, though feeble, touches.
Page 230 - ... magnet. The deflexion is ol served by the movement of a beam of light reflected from a small mirror on the Field = 10 15 25 35 62 102 200 400 600 Tube I.