American Telegraphy: Systems, Apparatus, OperationJ. H. Bunnell, 1892 - 563 pagine |
Altre edizioni - Visualizza tutto
American Telegraphy: Systems, Apparatus, Operation William Maver (Jr ) Anteprima non disponibile - 2015 |
Parole e frasi comuni
adjusted ampere apparatus armature lever arrangement artificial line attached automatic bell binding posts break-wheel cable caused cell central office circuit closed coil condenser conductor connected contact points core current strength cylinder deflection depressed desired device disc distant battery distant station duplex electrical electro-magnet electromotive force employed figure fire alarm flow galvanometer ground inch indicated instrument insulated iron joint resistance Leclanché cell letter line wire local battery loop magnet main line metal Morse needle neutral relay normally Ohm's law ohms operation paper paper tape passes placed plate plugs polarized relay pole pole-changer position potential practically quadruplex receiving repeating result reversals rheostat rotation screw segments semaphore shaft short-circuited shown in Fig shunt side signal box sounder strength of current strip switch tangent galvanometer telegraph telegraph system terminal terminal stations thereby ticker transmitter type-wheel volts Wheatstone Wheatstone bridge wheel zinc
Brani popolari
Pagina 279 - K' are adjustable by the indices », ;'. By this arrangement of fibres and springs it will be seen that any tendency of the coil- A to place itself at a right angle to the permanent magnets will deflect the siphon to the right or left, as the case may be, of the imaginary zero. The Cuttriss recorder, as it appears in practice, is shown in Fig.
Pagina 372 - A until acknowledged. Each station will then turn on a steady flash and adjust. When the adjustment is satisfactory to the called station, it will cut off its flash, and the calling station will proceed with its message.
Pagina 34 - The total resistance of a parallel circuit is equal to the reciprocal of the sum of the reciprocals of the individual resistances of the circuit.
Pagina 164 - Telegraphy. 157 the western circuit is closed at x', the lever /is held forward by its armature. In this way the function of the repeater in keeping closed the opposite transmitter, and virtually also the circuit which is being "repeated " into, is performed. Should the West now desire to '
Pagina 28 - DRY CELL. One form of dry cell, known as the Burnley, is shown in Fig. 10, in crosssection. In this cell the usual glass jar is replaced by a zinc tube, or cup A to which a clamping screw B, is rigidly attached, c is a solid carbon cylinder, forming the negative plate of the cell. It is provided with a connecting screw D. The zinc cup is lined with an exciting agent, E, which, practically, corresponds to the solution of the Leclanche cell, and is composed of sal-ammoniac, i part; chloride of zinc,...
Pagina 162 - R' also closes, consequently, so does T*; this action closes EM, and the lever of that instrument is withdrawn from its position against the lever R. This releases R'S lever, but, as now * See Transmitter, (continuity preserving) Duplex Telegraphy.
Pagina 12 - ... i . Further, since the current strength is equal to the quotient of the electromotive force divided by the resistance, it is evident that the resistance multiplied by the current strength will give the electromotive force. Hence, if the current strength or, as it is sometimes termed, the amperage, and the resistance of a circuit be known, the electromotive force will be represented by the formula E = c X B.
Pagina 372 - To start the sending station after breaking. -Signal '• GA " followed by the last word correctly received; the sender will immediately resume his message, beginning with the word indicated by the receiver. If nothing has been received signal
Pagina 12 - Ohm's law may therefore be expressed by the following equation: 1= * ~R where /is the current in amperes, E the electromotive force in volts and R the resistance in ohms. It is therefore evident, that if the electromotive force and...
Pagina 5 - C causes it to move along the rails to the right or left according to the direction of the current.