I have a project where I have an IR LED and an IR detector sensing the light. I'm running the output of the IR detector (which outputs a low voltage when IR light is detected) to the reset pin of a 555 timer that is supposed to flash a visible light LED. I attached the circuit I'm using to flash the LED. The only problem I'm having is that the LED is still on when the detector isn't detecting IR light. How can I make it so the LED is off when the detector doesn't sense IR light? Thanks.
edit: The output goes to a 2N3904 with a pull-up resistor to 5V. That goes to the reset pin of the 555 for the LED flasher, and also to both reset pins of two more 555s to create a siren.
edit: The output goes to a 2N3904 with a pull-up resistor to 5V. That goes to the reset pin of the 555 for the LED flasher, and also to both reset pins of two more 555s to create a siren.
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