Time-Delay Photo-Flash Trigger

Posted on Jan 20, 2013

Ql is a phototransistor that is normally illuminated by a beam of light. When the beam is intercoupled, pin

Time-Delay Photo-Flash Trigger
Click here to download the full size of the above Circuit.

1 of U1A goes high, and forces pin 4 U2B low. Then, C2 discharges through R2 and R3. After a certain time delay, pin 10 U1C goes high, triggers SCR1, and sets off the flash. R4/C1 charges, causes U1D output to go low after about 1h second, and resets U1A and U1B to the initial state. This delay prevents accidental double flash exposure.

Leave Comment

characters left:

Related Circuits

  • New Circuits



    Popular Circuits

    IR headphone transmitter CD4046
    Class A 2A3 audio Amplifier
    Adjustable 20V Supply Circuit
    Switch Timer For Bathroom Light
    Simple home audio power amplifier circuit schematic
    60W Linear amplifiers
    Multi-physics Model
    Units from the MAX4100 4101 gain buffer circuit diagram