. Practical wireless telegraphy; a complete text book for students of radio communication . e shunted by a condenser C-3, and an additional condenser C-4 isconnected between the grid and filament of the valve. The mode of operation of this circuitprobably does not differ from the repeating circuits previously described, because, as willbe seen, there is a certain amount of electrostatic and magnetic coupling between the second-ary and tertiary (local telephone circuit)circuits. The system is adjusted in the fol-lowing manner: The secondary circuit, in-cluding the secondary condenser, is tunedt
. Practical wireless telegraphy; a complete text book for students of radio communication . e shunted by a condenser C-3, and an additional condenser C-4 isconnected between the grid and filament of the valve. The mode of operation of this circuitprobably does not differ from the repeating circuits previously described, because, as willbe seen, there is a certain amount of electrostatic and magnetic coupling between the second-ary and tertiary (local telephone circuit)circuits. The system is adjusted in the fol-lowing manner: The secondary circuit, in-cluding the secondary condenser, is tunedto resonance with the primary circuit andthe incoming wave. The condenser C-1 isset at very low values of capacity, andthe capacity of C-3 varied, also C-4, untilmaximum response in the head telephonecircuit is obtained. Like ordinary vacuumvalve circuits, the potential of thebattery B-2 must be carefully regulatedand the valve worked below the charac-teristic blue glow point. The vacuumvalve connected in this manner is suitable for the reception of either damped or PHONES J Fig. 186—Cascade Connection of Vacuum Valve withOne Lighting Battery. RECEIVING CIRCUITS, DETECTORS, TUNING APPARATUS. 163 144. The Vacuum Valve Amplifier.—The incoming signals made audibleby the simple vacuum valve circuit shown in Fig. 179, may be amplified consider-ably by connecting several oscillation valves in cascade as per the diagram, The fluctuations of current in the local circuit are impressed upon the gridsof a second and third valve where due to the relaying or trigger action of the bulb,progressive amplification is obtained. VALVE Ni
Size: 2164px × 1155px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjecttelegra, bookyear1917
