METHOD AND APPARATUS FOR VIEWING A BORE HOLE

摘要

A down hole camera apparatus (10) includes a housing (12) for holding a camera (66) and a transmitter. The camera is adapted to capture and store a picture. The transmitter transmits the stored picture to a remote location at a frequency less than 7,000 Hz. Advantageously, this makes the apparatus compatible with operation over twisted pair cables (c) of the types standard in the industry. A receiving system (67) at the remote location receives the transmitted signal. Preferably, the receiving system includes a pair of receivers (198, 199). One receiver holds and displays a transmitted picture while another receiver simultaneously receives a picture being transmitted. A controller switches the operating mode of the receivers back and forth so that the display of the earlier picture and receipt of the next picture may be continuous if desired.