. QST . filtersbecome inoperative at frequencies severalhundred cycles on either side of the resonantfrequency. The T filter does not distort theIF passband seriously as does the crystal are effectively eliminated with littleloss of intelligibility. AVC A fast attack, slow release AVC system is em-ployed in the 75A-4. It will respond to thefirst few cycles of a sideband transmission anddoes not require the presence of a carrier foroperation. Fast and slow release times areselectable by means of a panel mounted con-trol. The fast is used normally for AM recep-tion. The slow i

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. QST . filtersbecome inoperative at frequencies severalhundred cycles on either side of the resonantfrequency. The T filter does not distort theIF passband seriously as does the crystal are effectively eliminated with littleloss of intelligibility. AVC A fast attack, slow release AVC system is em-ployed in the 75A-4. It will respond to thefirst few cycles of a sideband transmission anddoes not require the presence of a carrier foroperation. Fast and slow release times areselectable by means of a panel mounted con-trol. The fast is used normally for AM recep-tion. The slow is used during sideband and CWreception and prevents the receiver from open-ing up during words and characters. SEPARATE AM AND SSB DETECTORS Separate detectors are used for double or singlesideband signals. The single sideband detectoris a mixer type, which generates much less dis-tortion than a conventional diode detector ona SSSC signal. A diode detector is used forconventional double sideband lJWT\ I I

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Keywords: ., bookcentury1900, bookdecade1910, booksubjectradio, bookyear1915