. The Bell System technical journal . Fig. 38.—The Rieke diagram of Fig. 37 transformed to apply to the oscillator loadedfor optimum power at unity standing wave. B. Frequency—Sensitive Loads—Long Line Efect When the load presented to a reflex oscillator consists of a long line mis-matched at the far end, or contains a resonant element, the operation of areflex oscillator, and especially its electronic tuning, may be very seriouslyaffected. For instance, consider the simple circuit shown in Fig. 40. Here Mris the characteristic admittance of the reflex oscillator resonator as seenfrom the outp
. The Bell System technical journal . Fig. 38.—The Rieke diagram of Fig. 37 transformed to apply to the oscillator loadedfor optimum power at unity standing wave. B. Frequency—Sensitive Loads—Long Line Efect When the load presented to a reflex oscillator consists of a long line mis-matched at the far end, or contains a resonant element, the operation of areflex oscillator, and especially its electronic tuning, may be very seriouslyaffected. For instance, consider the simple circuit shown in Fig. 40. Here Mris the characteristic admittance of the reflex oscillator resonator as seenfrom the output line or wave guide and Ml is the characteristic impedanceof a line load I long, so terminated as to give a standing wave ratio, <r. 524 BELL SYSTEM TECHNICAL JOURNAL In the simple circuit assumed there are essentially three variables; (1)the ratio of the characteristic admittance of the resonant circuit, Af« to LOAD POWER. Fig. 39.—The Rieke diagram of Fig. 38 transformed to include the effect of a hne fivewave lengths long between the load and the oscillator. Mr M|_ Fig. 40.—Equivalent circuit of a lossless resonator, a line and a mismatched load. that of the line, Mi, . This ratio will be called the external Q and signifiedhyQ, Q, = Mn/M^ . () REFLEX OSCILLA TORS 525 For a lossless resonator and unity standing wave ratio, the loaded Q is equalto Qe ■ For a resonator of unloaded Q, Q», and for unity standing waveratio, the loaded Q, obeys the relation \/Q = \/Qe + 1/( ()
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