| 摘要 |
PURPOSE: A noise level detecting device for a power line is provided to help a user easily to recognize electrical noise level. CONSTITUTION: A power supply circuit(11) receives the commercial power of a consent and drops a voltage, and it converts it to DC voltage. A filter(12) receives the commercial power from the power supply unit and shields a predetermined frequency band through filtering. An amplifying circuit(13) stably amplifies the filter signal. An A/D converting circuit(14) converts amplified analog signal into a digital signal. A display unit(15) displays the noise level of the power line which is converted into a digital signal through the A/D converting circuit. |
