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  1. #1
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    water level indicator

    hi guys..
    Im doing project on water level indicator, I have designed water level sensor using transistor BC547.(circuit is attached)
    The LED glows when probes touches the water. the output of the sensor is given to microcontroller.
    I need some 5v to drive the port pins. but sensor output is below 3 volts. what can i do to get 5v and if I can amplify it, please provide the amplifier circuit.

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  2. #2
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    Re: water level indicator

    I have a problem , in that your words do not match the circuit. There is no LED in the circuit. To make sure that the transistors turn on connect a high value resistor between their bases and the +Vcc - 1 meg X 4?
    Frank



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  3. #3
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    Re: water level indicator

    sorry about the circuit, here is the one I have attached



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  4. #4
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    Re: water level indicator

    why do you need a LED in the probe? You are losing 1v6 by including it. AC on the probe is generally preferred.



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