Wireless Telegraphy and Telephony
Forfatter: Alfred P. Morgan
År: 1917
Forlag: The Norman W. Henley Publishing Company
Sted: New York
Udgave: Third Edition, Fully Illustrated
Sider: 33
UDK: 621.396.1 Mor
A practical Treatise on Wireless Telegraphy and Telephony, giving Complete and Detailed Explanations of the Theory and Practice of Modern Radio Apparatus and its Present Day Applications, together with a chapter on the possibilities of its Future Development
Søgning i bogen
Den bedste måde at søge i bogen er ved at downloade PDF'en og søge i den.
Derved får du fremhævet ordene visuelt direkte på billedet af siden.
Digitaliseret bog
Bogens tekst er maskinlæst, så der kan være en del fejl og mangler.
WIRELESS TELEGRAPHY 53
in the proper direction to form a magnetic field flowing in
the same direction as that of the permanent magnet will
strengthen the latter and assist it in attracting the di-
aphragm and causing it to further approach the magnet.
That portion of the current flowing in the opposite direc-
tion detracts from the magnetic pull and allows the di-
Fig. 65.—Pickard adjustable telephone receivers for wireless purposes.
aphragm to recede from the magnet. The diaphragm thus
takes up a vibrating motion corresponding to the electrical
waves supplied to the coil and it imparts motion to the
surrounding air, the result being sound.
It might reasonably be asked why a telephone receiver
could not be directly connected to the aerial and ground
so that it would respond directly to the high frequency
currents generated by the incoming waves without the me-
dium of a detector. There are two very good reasons why
such a method would not be possible, the first being that