Incandescent lamp life extension circuit 4

(4) Incandescent lamp life extension circuit No. 4
    The circuit is shown in Figure 2-32. It is formed by connecting a photoresistor RG to a conventional trigger circuit . The dark resistance of the photoresistor is greater than 4Mfl, and the bright resistance is less than 5kfl. The photoresistor is located at the appropriate location where the light bulb illuminates. Turn on the switch SA and the light will gradually turn from dark to full brightness. The soft start time can be changed by adjusting the distance between the photoresistor RG and the light bulb or the values ​​of Ri and C. Generally, it takes a few tenths to several seconds for the bulb to reach normal brightness.