| 摘要 |
A time measuring circuit for meters of the pulse reflection type includes a gate signal generator for producing a gate pulse signal the duration of which is proportional to a value of an object to be measured, an oscillator for producing clock pulses at a predetermined frequency, a complementary-output element responsive to the gate pulse signal for producing first and second clock pulses which are the same at their phase and relatively inverted, a pair of gates for passing therethrough the first and second clock pulses during appearance of the gate pulse signal, a flip-flop for applying the first clock pulses to a counter and for applying the first and second clock pulses to a pair of integration circuits. The counter counts the first clock pulses to produce an output signal indicative of the counted value, and the integration circuits selectively integrate the first and second clock pulses in response to the gate pulse signal. An analog-to-digital converter is connected to the integration circuits to convert the finally integrated value into a digital value, and a computer is arranged to calculate a sum of the counted value and the digital value.
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