. The Bell System technical journal . (b) y,-y-* Fig. 11—Effective band width of a phase sensitive detector Sveit = that the band width of tlie amplifier does not enter as long as ^vi < vi . 482 THE BELL SYSTEM TECHNICAL JOURNAL, MARCH 1957 In order to see what maximum gain G (60) imposes on a typical sys-tem we assume AFjf = 5 X 10^ Z = 10l2; Vc ^ IV. Underthose conditions we get from (60) that G has to be smaller than approxi-mately 10^ If on the other hand G is very small the signal level at theaudio amplifier input is so low that the flicker noise of the detector cans
. The Bell System technical journal . (b) y,-y-* Fig. 11—Effective band width of a phase sensitive detector Sveit = that the band width of tlie amplifier does not enter as long as ^vi < vi . 482 THE BELL SYSTEM TECHNICAL JOURNAL, MARCH 1957 In order to see what maximum gain G (60) imposes on a typical sys-tem we assume AFjf = 5 X 10^ Z = 10l2; Vc ^ IV. Underthose conditions we get from (60) that G has to be smaller than approxi-mately 10^ If on the other hand G is very small the signal level at theaudio amplifier input is so low that the flicker noise of the detector canstill come in. A good practical figure for the IF amplifier gain is around60 db. VIII. SATURATION EFFECTS In all the previous considerations RF power saturation effects wereneglected, , we have assumed that the power absorbed is proportionalto Hi, where Hi is the RF magnetic field. When this assumption is nolonger satisfied, the question of sensitivity has to be re-examined fordifferent degrees of saturation. However it is diffi
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
