Abstract: The present invention is directed to a non-contact detector for sensing a periodically varying magnetic field. The non-contact detector includes a probe having at least one magnetic sensor used to sense a magnetic environment generated by current running through a conductor. The detector includes means for periodically varying the magnetic environment and sensing means that is associated with each magnetic sensor that produces an electrical signal representative of the change in the magnetic environment. The detector also includes means for delivering a usable representation to a user in response to the sensing of the periodically varying magnetic environment.

Abstract: A multiple phase CRC (cyclic redundancy check) generator having a clock phasing circuit having an input connected to the CRC clock source and a plurality of N phase clock outputs, and a plurality of N CRC circuits each having a data input, and a phase clock input each connected to one of the clock phasing circuit phase clock outputs, and each having a cyclic redundancy check output. The clock phasing circuit preferably is formed of a sequence of divided-by-two circuits each having an input and two outputs; there being N-1 divider circuits arranged in log.sub.2 N tiers, the divider circuits of the first tier having its input connected to the clock output and the outputs of the last tier of divider circuits each being connected to separate clock inputs of the CRC circuits.