Abstract: A transmission measuring system includes a subject for transmission measurement for outputting, in response to a start signal for measurement from a central processing unit, an output signal including information on a transmission time to be measured. An analog-digital converter converts the output signal into digital data. The central processing unit processes the digital data to obtain the transmission time required for propagating the signal through the subject. A clock signal source provides a clock signal to the central processing unit, and a variable delay unit is interposed between the clock signal source and the analog-digital converter. The central processing unit delivers a delay time control signal to the variable delay unit so that the delay time of the clock signal of the analog-digital converter may be varied with time relative to the start signal for measurement.

Abstract: To provide an industrially advantageous transmission measuring system of sufficiently high time resolution, i. e. the system that can make measurement in high accuracy without using expensive analog-digital converter.