. The principles underlying radio communication . pedwave is interrupted at the transmitting station at an audiblefrequency by a chopper, the wave radiated affects receivingapparatus in some ways as if it were a damped wave. 353 354 TRANSMITTING APPARATUS. 154. Simple Spark Discharge Apparatus.—Damped oscilla-tions are produced when a condenser discharges in a circuitcontaining inductance. The condenser is discharged by plac-ing it in series with a spark gap and applying a voltage to ithigh enough to break down or spark across the gap. As ex-plained in Section 115, the oscillations produced wh
. The principles underlying radio communication . pedwave is interrupted at the transmitting station at an audiblefrequency by a chopper, the wave radiated affects receivingapparatus in some ways as if it were a damped wave. 353 354 TRANSMITTING APPARATUS. 154. Simple Spark Discharge Apparatus.—Damped oscilla-tions are produced when a condenser discharges in a circuitcontaining inductance. The condenser is discharged by plac-ing it in series with a spark gap and applying a voltage to ithigh enough to break down or spark across the gap. As ex-plained in Section 115, the oscillations produced when the con-denser discharges in such a circuit are damped and soon dieout. Methods of producing a regular succession of such con-denser discharges are explained in the following. A highvoltage must be applied to the condenser at regular is done by the use of a transformer. Through the primaryof the transformer is passed either an alternating current or a le -S^rrt diach«r£« a^^kratua. Quenched Sj»ar< Di*cKar^r current regularly interrupted by a vibrator operated by thetransformer (induction coil). For the use of the induction coil,as in radio trench sets, see Section 157. The principle is beststudied first in the alternating-current method. In Fig. 180, P and S are the primary and secondary of astep-up transformer (Section 58), which receives power froman generator. The primary may be wound for 110 volts,and the secondary for 5,000 to 20,000 volts. By means of thetransformer the condenser C is charged to a high voltage, andstores up energy. When the voltage becomes great enough itbreaks down the spark gap and the discharge takes place as anoscillatory current in the inductance coil L and its leads. SeeSection 115. The main discharge does not take place throughthe turns of S on account of its relatively high impedance. The SPARK GAPS. 355 transformer is sometimes still further protected from the con-denser discharge by inserting choke coils (not show
Size: 1359px × 1839px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, bookpublisherwashi, bookyear1922
