Recent content by lab19

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    Light sensor motor control

    I see this could also work. The circuit from Alec_t is a little simpler and seems to accomplish what I need. I will keep this in mind. Thanks for your help.
  2. L

    Light sensor motor control

    Indeed they do. I apologize for the sloppy drawing.
  3. L

    Light sensor motor control

    Your right. I didn't draw that very well. Actually the current flows through the motor and to the mosfet in the control circuit. The circuit diagram at the start of this thread shows the layout better.
  4. L

    Light sensor motor control

    This circuit works perfectly! Thank you everyone for your help. Just one other question that perhaps someone could help with. When I started working on this I began with another circuit I came across for a motor controlled by a light sensor. That circuit had a 2 ohm, 10 watt resistor at the...
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    Light sensor motor control

    I have not tried the pull down resistor yet. I have just been too busy lately! Hopefully tomorrow I can get back to it. I will let you know.
  6. L

    Light sensor motor control

    That is correct.
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    Light sensor motor control

    I am not sure how involved you want to get with this but maybe a better explanation of my project will help. I am making a machine to apply self adhesive labels. The motor is used to advance a roll of labels until the light sensor sees a gap between labels on a roll. At that point the motor...
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    Light sensor motor control

    The sensor has 2 output transistors, an npn (sink) and a pnp (source). I am using the pnp output so I think it would be a pull-up. I will give the resistor a try.
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    Light sensor motor control

    I wasn't quite sure what a capacitor-couple was but I tried adding the capacitor between the sensor and the reset as shown on the schematic. This did not work for me. The reset pin always was low regardless of the sensor output. Maybe I have set this up wrong. My sensor uses a transistor to...
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    Light sensor motor control

    I will give this a try tomorrow. Thank you!
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    Light sensor motor control

    My problem is that the motor will not start if the sensor sees light. Maybe the problem is that it is actually restarting but it is instantly stopping because the sensor sees light. I need the motor to stop only when the sensor goes from dark to light. The motor should be able to run when the...
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    Light sensor motor control

    I think I am using it as a latch. I am not using the timer function of the 555 anyhow. I am using the sensor output to turn off the motor and it should stay off until I manually restart it with a switch (producing a negative pulse on the trigger- pin 2).
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    Light sensor motor control

    I am trying to make a device to run a DC motor based on the output from a light sensor. The sensor has an on/off output (12V/0V). It can be set to turn on when it senses light or turn on when it senses dark. I would like the motor to turn off when the sensor detects light but I want to manually...
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