Abstract: A magnetic field coupler has a plurality of magnetic poles with respective first ends located immediately adjacent a circular path of a rotating magnet in a meter. The magnetic poles have respective opposite ends located immediately adjacent a magnetic sensor in a meter reading device. A nonmagnetic material separates each of the plurality of poles from all others of the plurality of the poles, and the nonmagnetic material is joined with the poles to form a unitary structure.

Abstract: A shelf tag printing system includes a portable terminal in radio communication with a base station and a portable printer in wireless communication with the portable terminal. The portable terminal has a bar code scanner which reads product bar codes for radio transmission to the base station. The base station responds with informational signals indicating legends to be printed upon shelf tags by the printer. These signals are received by the portable terminal and relayed to the printer. Communication between the portable terminal and the printer is one-way via a surface wave acoustic resonator in the portable terminal and an amplifier sequenced hybrid receiver in the printer.

Abstract: A shelf tag verifying apparatus having a portable terminal unit in radio communication with a base station and in acoustic wave communication with a nearby bar code reader. The bar code reader reads a bar code printed upon a product which rests upon shelving marked by a tag requiring verification. A decoder mounted within the bar code reader generates a binary product code corresponding to the bar code and appends a check code. A SAWR transmitter then transmits the binary product code and the check code to an ASH receiver mounted in the terminal unit. A microprocessor mounted in the terminal unit verifies the check code and generates a query for radio transmission to the base station, whereupon the base station responds with information for verification of the shelf tag.