GB738897A - Arrangement for use in the metering and recording of telephone calls - Google Patents

Abstract

738,897. Electric recording systems. TELEFON FABRIK AUTOMATIC AKTIESELSKAB. Nov. 25, 1952, No. 29873/52. Class 40 (1). [Also in Group XXXIX] A telephone subscriber's meter is arranged to control an electrical condition which in turn controls the making of a permanent record of the meter reading. As shown, Fig. 1, the meter controls a variable resistance 1 which is connected to the bridge 4. The diagonal current controls the position of the punch 6 which is operated by the magnet 7 to perforate the tape 9. In modifications the variable resistance is replaced by a variable inductance, Fig. 2 (not shown), or a variable condenser, Fig. 3 (not shown), the bridge being fed by A.C. In a further embodiment, Fig. 4, in which metering takes place according to the nature and duration of the call, continuous metering current causes mercury 16 to pass through a fine mesh screen 17 in contact with electrolyte contained in the lower vessel. The mercury in falling to the bottom of the vessel progressively shortcircuits a resistance 18 which controls the recording mechanism as before. An alarm contact 27 is provided to indicate when the meter must be reset. In a further modification of this type, the resistance is caused to vary by direct electrolytic deposition, Fig. 5 (not shown). In a further modification a resonant circuit is formed by an inductance and a capacity which are changed by the 1000s and 100s wheels of the meter respectively and means is provided for determining the resonant frequency.