. The A B C of vacuum tubes in radio reception; an elementary and practical book on the theory and operation of vacuum tubes as detectors and amplifiers. Explains non-mathematically the fundamental principles upon which all vacuum tube circuits are based. Includes practical circuits and practical questions and answers. It is written especially for the beginner. All electrical and radio terms are fully explained . the grid circuit VACUUM TUBE AMPLIFIER 81 and connecting the negative battery terminal to the and better method is to include a portion of the fila- 100908070 +.-60 c I 5
. The A B C of vacuum tubes in radio reception; an elementary and practical book on the theory and operation of vacuum tubes as detectors and amplifiers. Explains non-mathematically the fundamental principles upon which all vacuum tube circuits are based. Includes practical circuits and practical questions and answers. It is written especially for the beginner. All electrical and radio terms are fully explained . the grid circuit VACUUM TUBE AMPLIFIER 81 and connecting the negative battery terminal to the and better method is to include a portion of the fila- 100908070 +.-60 c I 50o 40302010 v^/ P/rat/ht 7 \ v .___. .___ Po/hi t. P/afe &///< ent s Norm il PI a te Cut i rent *a // / / ■*-. // / t.—,—i ■fc -A/_. _\Z_ -■— l<3 ! ^ ~~ ^ Fig. 30—Amplification of continuous oscillations ment rheostat resistance in the grid circuit as shown in Fig. places a negative potential upon the grid which is equalto the potential difference between the points X and Y. 82 A B C OF VACUUM TUBES The audiofrequency variations of plate current in the detec-tor tube now cause grid potential variations in the amplifiertube which are larger in amplitude than the grid potential vari- Transformer Grid-, Plate To PlateCircuit ofDetectorTube. u Amplif ier\lube JL r Filament ■?%4-*/sRheostat Filament )Battery •= Plate— Battery -© Fig. 31—Customary method of placing a normal negative potential onthe grid of an amplifier tube. ations applied to the detector tube by the antenna variations of amplifier grid potential will be at dieaudible frequency rate because radio frequency current vari-ations cannot readily flow in the detector plate circuit due tothe high reactance of the transformer primary. Audio-frequency currents will then flow in the plate circuit of theamplifier tube and through the telephone receiver. The receiverdiaphragm will vibrate with greater amplitude because thecurrent variations are of magnifi
Size: 1294px × 1931px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, bookidabcofvacuumt, bookyear1922
