| 摘要 |
In preferred form, a time delay circuit including a light dependent variable resistance device having a housing divided into two compartments. A light source is located in one of the compartments and a light dependent resistor having a high dark resistance and a lower resistance when exposed to light is located in the other compartment. A photochromic lens is interposed between the light and the light dependent resistor to produce a timed control of the resistance value of the device. The device is connected in circuit with an electrical load by means of a single switch and a network that will simultaneously energize the light, the light dependent resistor, and load.
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