| 摘要 |
PURPOSE:To make the most of simplicity of a circuit configuration of a gate system, and to execute measurement and display with satisfactory response property and high accuracy, by multiplying a signal corresponding to engine rotational frequency of a vehicle, counting it for a prescribed period, and displaying a counting value. CONSTITUTION:A signal fin corresponding to rotational frequency of an engine, which is obtained from an input signal part 11 is applied to a multiplying circuit 12. Also, to this circuit 12, a basic signal f0 from a frequency-dividing circuit 15 is applied, and in accordance with the f0, a signal fm which has multiplied frequency of the fin is formed, and is applied to one input terminal of an AND circuit 13. On the other hand, a signal which has frequency-divided 16 the f0 is applied to a circuit 17, and a gate signal G for opening the circuit 13 for a prescribed period, a reset signal R for a counter 18, and a latch signal L of a latching circuit 19 are formed. In this way, frequency of the fin is made higher by the circuit 12, and this signal is inputted and counted in the counter 18 for a prescribed period through the circuit 13, and is displayed on an indicator 21. |
