. The Bell System technical journal . l<y 04 10- n. 2? °3 R3 2° 3^ * * » \AA; t * \. FROM DCAMPLIFIER positions: 1. OFF 2. OPERATE 3. RELEASE 4. OPERATE R4 f\J\f\ +165 V

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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1