Electrical news and engineering . maximum magnification. Thefilament and plate of the modulating tube are shuntedthe plan- circuit of the oscillating tube [he audi., frequencj radio frequency circuits arc coupli I with the proper phase choke L. may be said to act as a one trans ormi relation, any variation of voltage in either the grid or platecircuits will cause minute disturbances in the oscillation setting them into oscillation it whatevithey happen to be adjusted to I or example, a slight varia-tion of voltage in the plal ircuit by any means whatSOever, will cause its resonant i
Electrical news and engineering . maximum magnification. Thefilament and plate of the modulating tube are shuntedthe plan- circuit of the oscillating tube [he audi., frequencj radio frequency circuits arc coupli I with the proper phase choke L. may be said to act as a one trans ormi relation, any variation of voltage in either the grid or platecircuits will cause minute disturbances in the oscillation setting them into oscillation it whatevithey happen to be adjusted to I or example, a slight varia-tion of voltage in the plal ircuit by any means whatSOever, will cause its resonant itate al radPiiicy, and the resultan. currents will act upon the idio frequency chol t ents the radii i currents developed bj the oscillator from Rowing back to theplati circuit generatoi G Ct is a protective condenser forthe plate circuit generator, When the transmitter M is spoken into, speechof variable frequem i ited bj the microphone arc un-ci upon the grid circuit ol the the i Mating lube. THE ELECTRICAL NEWS August 15, 1919. Fig. 1—Fundamental circuits of the wireless telephone transmitter lor seapla and, through the medium of the auto transformer Lj, alter-nating currents are superposed upon the plate circuit ofthe oscillator. This in turn varies the amplitude oi the os-cillator currents at speech frequencies, and accordingly theamplitude of the radio frequency oscillations flowing in theantenna circuit. It is essential that the key Ki of figure 1he closed for the production of undamped oscillations, forwhen it is open the tube stops oscillation. Manipulation ofthis key permits telegraphic signalling by the undamped os-i illations produced by the tube. Telegraphy by Damped Oscillations When it is desired to telegraph by damped oscillations,the change over switch Si is thrown from the microphoneto the buzzer B which is energized by the battery Bi. Theinterrupted currents fed by the buzzer through the primaryii of the induction coil produce alternating currents of higher
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Keywords: ., bo, bookcentury1800, bookdecade1890, bookidelectricalnewsen28donm
