Telephone Apparatus: An Introduction to the Development and TheoryD. Appleton, 1917 - 337 σελίδες |
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Συχνά εμφανιζόμενοι όροι και φράσεις
air-gap alternating current Amer amperes apparatus Appendix armature battery bell carbon centimeter central energy changes components condenser conductor connected cord circuit counter-electromotive force curve cycles per second diaphragm dielectric direct current distance effect Elec electromagnetic electromotive force electrostatic equal equation exchange Fkln footnote frequency hysteresis increases induction coil Inst insulation iron core Jour June less magnetic circuit magnetic field magnetic flux magnetomotive force maximum MCMEEN and MILLER microphone netic ohms operator oscillograms path permanent magnet permeability Phil phragm pitch polarized ringer pole pole-changers Proc pull pulsating quency reactance relay reluctance rent repeating coil resistance resonance ringing secondary currents self-induction sensitiveness signaling sinusoidal sound steady tele telegraph Telephone Practice telephone receiver telephonic currents tion Trans transmitter U. S. Patent VANDEVENTER variation varying vibrations voice currents vowel WIETLISBACH windings wire York
Δημοφιλή αποσπάσματα
Σελίδα 47 - MAGAZINE. 97 19o1.] [MARCH, stand d and presses against the plate, which pressure, however, can be regulated by the thumb-screw attached to the ball. If a current of electricity passes thru the plate and the point of contact, or vice versa, a repulsive movement will take place between the plate and the ball, because both are charged with the same kind of electricity. This force of repulsion may be weakened or strengthened by varying the strength of the current.
Σελίδα 22 - Anatomy. — The organ of voice, the larynx, is situated in man in the upper and fore part of the neck, where it forms a well-known prominence in the middle line. It opens below into the trachea or windpipe, and above into the cavity of the pharynx, and it consists of a framework of cartilages, connected by elastic membranes or ligaments, two of which constitute the true vocal cords. These cartilages are movable on each other by the action of various muscles, which thus regulate the position and...
Σελίδα 188 - ... ratio of the difference between the maximum and minimum velocities in an engine-cycle to the average velocity. 80 Capacity. The two different senses in which this word is used sometimes lead to ambiguity. It is therefore recommended that whenever such ambiguity is likely to arise, the descriptive term power capacity or current capacity be used, when referring to the power or current which a device can safely carry, and that the term " Capacitance " be used when referring to the electrostatic...
Σελίδα 217 - Resistance. —The resistance of any conductor is directly proportional to its length, and inversely proportional to its area of cross-section, or R = K — , where K is a constant.
Σελίδα 21 - ... which is a necessary result of a consideration of the general phenomena of voluntary action — seems to have been what PAUL had in mind. ‘ An actual separation of a word into its elements is not only very difficult, it is actually impossible. A word is not a placing side by side of a definite number of independent sounds, each of which can be expressed by a letter of the alphabet, but is nearly always a continuous series of an infinite number of sounds, and the letters indicate, in an incomplete...
Σελίδα 184 - The force required for bending the spring a given distance is directly proportional to the sectional area and inversely proportional to the length of the spring.
Σελίδα 315 - Davy, to whose great work we are soon coming, also discovered independently the power of the electric current to magnetize iron and steel...
Σελίδα 81 - ... receivers. When used as a transmitter, the sound vibrations of the air actuate the telephone. The intensity of vibration in this case is given, but there is an unlimited volume of vibrating air at our disposal. According to an experiment by Siemens, the force of the air vibrations operating upon the transmitter is ten thousand times greater than that of the vibrations reproduced by the receiver. Even if this proportion be not generally true, it must certainly be conceded that the force acting...
Σελίδα 66 - It operates first as a part of the magnetic system, incidentally as part of the electric system, and finally as a mechanical vibrating system. In each of these relations, faithful reproduction of the original sound...
Σελίδα 284 - A circuit has a self inductance of one henry if a change in the current at the rate of one ampere per second gives rise to an induced emf of one volt. m, . • t , , » — 77777 KS henries The practical henry equals < 9x 10