Electronic mailbox front door
This circuit is integrated electronic mailbox,A front door open.And when people open. Cabinet photo detector attached to the light, it will work.
Operation of the circuit.While not open the mailbox PHOTO1 will not bias. The voltage at C2 is approximately 9 volts, it is charged through R3.
The BE voltage of Q1 is not enough leg to bias the Q1 does not work. When open mailbox PHOTO1 to work, the voltage at C2 is “0″. The C2 begin to charge new.Between the C2 begin to charge the pressure to bias the BE pin of Q1. It works to stimulate the G pin of SCR1.The C1 is noise signal protection.When SCR1 to work to work and hold a current flows through LED1.LED1 light makes it through until the switch S1.To start a new cycle.
Categories: Detector Tags: Light Detector, phototransistor circuits
Simple Light Actuated Relay by Phototransistor
The Sun – Up Relay Switch can be used to provide a audible switch for when the sun comes up. It can also be used to detect a light beam, headlights etc.
This circuit is easy because it used one Transistor 2N2222-2SC945-2SC828-BC549 etc , Relay and Photo transistor Only. The important part of the circuit is very low cost. (I like it)
The photo transistor is very sensitive to light. VR1 for control sensitive of circuit.
Relay used 6V to 9V 600ohm.
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Categories: Detector, Lighting Tags: light switch, lighting senser, phototransistor circuits
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