| 摘要 |
PCT No. PCT/GB93/00572 Sec. 371 Date Dec. 8, 1994 Sec. 102(e) Date Dec. 8, 1994 PCT Filed Mar. 19, 1993 PCT Pub. No. WO93/19439 PCT Pub. Date Sep. 30, 1993A remote meter reading system, for example for domestic water meters, operates through an inductive coupling over two lines. A sinusoidal power signal is transmitted from a reader to the meter to power up encoding circuitry in the meter. The encoding circuitry then transmits data by intermittently shorting the input terminals to cause an asynchronous voltage modulation at the reader. There is no synchronous relationship required between the periodic power signal and the data transmitted from the encoder to the reader.
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