| 摘要 |
PURPOSE:To eliminate malfunctions at an operating power supply time and to extend the holding duration due to a holding power source in the device which has an RAM for storage of frequency information and has a function (power on clear function) by which contents of the RAM are initialized when the operating power for a receiver is turned on again. CONSTITUTION:The first memory 17 is an RAM to store plural frequency information, and the second memory 18 is an RAM to store a specific value (for example, 1,100), and power is fed to both RAMs from a holding power source 21 (capacitor) commonly. When an operating power switch 22 for a receiver is turned on, it is decided by a detecting circuit 23 whether contents of the second memory 18 are a specific value or not; and if they are not the specific value (contents of the memory 17 are destructed also in this case), the memory 17 is initialized by a control circuit 19, and the specific value is written into the memory 18. Thus, the holding voltage is lowered to the limit of the threshold voltage of the RAM. |
