Patent ID: 9255999
Filing Date: 2016-02-09
CPC Classification: G01V

Claim Text:
1. A portable seismic recorder comprising: electronic recording circuitry including a processor, memory, an analog-to-digital converter, and an oscillating clock circuit, said analog-to-digital converter being arranged for sampling and digitizing a signal from an analog seismic sensor at a frequency and a timing determined by said oscillating clock circuit, said processor and memory being arranged to store digitized seismic data sampled over an extended sampling period by said analog-to-digital converter; and a radio receiver arranged to produce an output timing signal in synchronism with a time standard using one or more broadcast radio signals, said radio receiver being selectively coupled by said processor to said oscillating clock circuit so as to periodically synchronize operation of said oscillating clock circuit to said output timing signal of said radio receiver by cycling said radio receiver between enabled states in which said oscillating clock circuit is disciplined to said output timing signal and idle states in which said oscillating clock runs autonomously; whereby said analog-to-digital converter is enabled to continually digitize and sample said signal from said analog seismic sensor for said extended sampling period as paced by said oscillating clock circuit while said oscillating clock circuit remains synchronous with said time standard within a predetermined tolerance without continuous operation of said radio receiver.