. Practical wireless telegraphy; a complete text book for students of radio communication . also has the shuntcondenser C-2. By variation of the capacity of C-1 and C-2, the grid circuit and anodecircuit may be tuned to resonance and the oscillations flowing in the anode circuit repeatedback to and reinforced through the grid circuit by inductively coupling coil L to means of a third winding, L-3, coupled to either L or L-2, current of any desired frequency can be gen-erated by proper varia-tion of inductance andcapacity; in fact, cur-rent at frequencies from60 to 1,000,000 cyclesper se
. Practical wireless telegraphy; a complete text book for students of radio communication . also has the shuntcondenser C-2. By variation of the capacity of C-1 and C-2, the grid circuit and anodecircuit may be tuned to resonance and the oscillations flowing in the anode circuit repeatedback to and reinforced through the grid circuit by inductively coupling coil L to means of a third winding, L-3, coupled to either L or L-2, current of any desired frequency can be gen-erated by proper varia-tion of inductance andcapacity; in fact, cur-rent at frequencies from60 to 1,000,000 cyclesper second can be ob-tained. The radio-frequentcurrents generated inthe circuits of thePliotron can be trans-ferred to the antennasystem by connectingthe terminals of thecoil L-3 to the antennaand earth wire, theprecaution being takento tune the aerial cir-cuit to resonance withthe local current. Anumber of Pliotronsmay be connected inparallel and direct cur-rent at any desiredpower converted intooscillations of radio-frequency. The Pliotron vacuumbulb can also be used tovary the amplitude of. Fig. 288—The Pliotron Oscillator Connected for theFrequency Oscillations. Production of Radio- the oscillations in an antenna system traversed by undamped oscillations. If properly connected, it is applicable for raddo-telephony as well as telegraphy. If the anode of the Pliotronis connected to a point of high potential in the antenna system and the negative side ofthe filament to earth, and the grid potential of the Pliotron is strongly negative, no leakageto earth takes place, but if the negative potential is decreased, sufficient energy will be with-drawn from the antenna to strongly damp the oscillations. In fact, practically all the energyof the antenna oscillations can thus be diverted to earth. If an external electromotive force of the correct value is impressed upon the gridthrough a small telegraph key, the dots and dashes of the Morse code are formed by simplyclosing the circ
Size: 1439px × 1736px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjecttelegra, bookyear1917
