| 摘要 |
PURPOSE:To report that the electromotive force of a battery drops by generating an information signal by the output of a sensor which detects a source voltage being lower than a specific value by a timing signal. CONSTITUTION:When a power source 10 is turned on, a power source control circuit 8 operates by the output of a timing generation control circuit 4 to supply electric power intermittently to a receiving circuit, which enters an intermittent receiving operation. The low-voltage sensor 7 is controlled by the circuit 4 to check the feeding voltage of the battery 9 intermittently, and when the feeding voltage drops, the coincidence between the output of the sensor 7 and the timing output of the circuit 4 is obtained by an AND gate 5 to control a sound generating circuit 6 through a control circuit 6a, generating a sound through a speaker. Thus, error detection due to a noise generated in power-off operation is eliminated to report accurately a drop in battery feeding voltage. |
