Hi! I found a moisture sensing circuit by searching the forum here, originally posted by Audioguru (schematic attached). I'd like to interface this moisture sensing circuit with an HM-11 Bluetooth module, with the Bluetooth module reading the voltage on one of it's input pins and transmitting that value. This seems pretty simple to do, based on the "HM-10 Stand-alone: Remote Light Sensor" demo project here http://www.martyncurrey.com/hm-10-bluetooth-4ble-modules/
However, I'd like to "invert" the output of the moisture sensing circuit so that the output signal/voltage increases with an increase in moisture between the probes (rather than having the output increase with decreasing moisture between the probes, as it does in the attached schematic). So basically the circuit and Bluetooth transmitter only start to signal when moisture is detected between the probes. Also, I'd like to know how easy it would be (or which component values can be altered) to decrease the measurement/output pulse rate to, say, once a minute to reduce the power consumption of the circuit. The HM-11 Bluetooth module will run on 3V, and this is the only moisture sensing circuit (Audioguru's) I've found so far that is low voltage.
My background is mechanical engineering, and while I can read a schematic and assemble electronics, design-wise I'm hopeless!
However, I'd like to "invert" the output of the moisture sensing circuit so that the output signal/voltage increases with an increase in moisture between the probes (rather than having the output increase with decreasing moisture between the probes, as it does in the attached schematic). So basically the circuit and Bluetooth transmitter only start to signal when moisture is detected between the probes. Also, I'd like to know how easy it would be (or which component values can be altered) to decrease the measurement/output pulse rate to, say, once a minute to reduce the power consumption of the circuit. The HM-11 Bluetooth module will run on 3V, and this is the only moisture sensing circuit (Audioguru's) I've found so far that is low voltage.
My background is mechanical engineering, and while I can read a schematic and assemble electronics, design-wise I'm hopeless!
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