Abstract: A telemetry apparatus is disclosed for reading utility meters. The apparatus includes a meter-base unit 10 mounted in a conventional utility meter and comprising a plurality of sensors (18a-18e) positioned to sense numerical data displayed on a conventional meter number wheel set 13. Sensors 18a through 18e preferably comprise pads 52 positioned on the face of wheels 13 which are sensed by feather switches 55. The signals are processed by a microprocessor and are converted from parallel to serial form and transmitted in a bit stream to the mobile unit 30. A security circuit 50 is provided for sensing whether the meter-based unit 10 has been tampered with. The security circuit 50 includes operational amplifier sections 74a and 74b which operate as latches to hold the voltage at a predetermined position if the flow of current through a current loop 51 is interrupted. The mobile unit 50 includes a key pad 33 through which the meter-based unit 10 can be interrogated by a transmitter 36.

Abstract: An electro-optical encoder is disclosed of the type used for reading utility meters. The encoder includes at least one light source for directing light onto the edge of the rotating disk of the utility meter. At least one sensor receives information reflected from the metered disk in pulse form upon sensing the calibration mark on the disk. A compensation circuit is connected to the sensor for detecting spurious information reflected from the disk and compensating for the spurious information to produce an accurate signal reflecting metered product usage for delivery to a final output. The compensation circuit includes a counter for being set to an integer corresponding to an empirically determined number of pulses sensed by the sensor during a single rotation of the meter disk. The counter counts down to one and then transmits downstream a single pulse representing one revolution of the meter disk and is then reset.

Abstract: A time synchronizer is disclosed for an analog timepiece. An electronic circuit 20 is disclosed which generates a direct current pulse upon receipt of an input signal from a remote source. Circuit 20 is operable in two separate modes through outputs from a timekeeping output 25 and a time correction output 38. The time correction mode operates through a feather switch 35 having a contact 35b which rides in a cam 34 of a rotating wheel 33 which moves in synchronization with hands 12A and 12B of an analog timepiece.