. Practical wireless telegraphy; a complete text book for students of radio communication . iave this operating characteristic whenfitted with a magnetic leakage gap shown by the dotted line, Fig. 37. Through the leakageprovided by this gap, the self-inductance of the primary winding remains nearly constantunder all variations of the secondary load. Both the open and closed core transformers are employed in wireless telegraphy togenerate current at voltages between ten thousand and fifty thousand volts at power inputsvarying from V^ K. W. to 500 K. W. , . The ratio of transformation in the ope
. Practical wireless telegraphy; a complete text book for students of radio communication . iave this operating characteristic whenfitted with a magnetic leakage gap shown by the dotted line, Fig. 37. Through the leakageprovided by this gap, the self-inductance of the primary winding remains nearly constantunder all variations of the secondary load. Both the open and closed core transformers are employed in wireless telegraphy togenerate current at voltages between ten thousand and fifty thousand volts at power inputsvarying from V^ K. W. to 500 K. W. , . The ratio of transformation in the open core transformer is not exactly m proportionto the turns, due to magnetic leakage. The design is, therefore, altered to meet theseconditions. Generally the secondary is given more turns than the usual transformer equation would require. . ■ -c- in -, The so-called auto transformer with a step-up ratio of turns is shown in fig. 39. Inthis type the primary and secondary windings have turns in common, a single coil being ■Open Core Transformer. 36 PRACTICAL WIRELESS TELEGRAPHY. I. Fig. 39—^Auto Transformer. used for both circuits. A portion of the current flowing in the secondary winding is in-duced by the passing of the flux through the core from the primary turns, but anotherportion flows into the secondary circuit by direct conduction. Although transformers of this type are not employed for the production of high voltages(with low frequency currents), they are frequently used as step-down transformers to obtain 10 to 30 volts of alternating cur-rent from a 110-volt source. Without aniron core, auto transformers are used inthe circuits of radio frequency in boththe transmitting and receiving apparatusof wireless telegraphy. The air core transformer in Fig. 40 isused principally in radio-frequency cir-cuits for transferring oscillations at ex-tremely high frequencies from one circuitto another, and when used in this man-ner it might properly be called a radio-frequency tr
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Keywords: ., bookcentury1900, bookdecade1910, booksubjecttelegra, bookyear1917
