Simple solar plant watering alarm
Meters & Detectors
This is a simple Solar plant watering alarm circuit. It will sound alarms when the soil is dry. The trees have died. It the solar sell is 6V DC power supply. Thus saving convenience and does not require batteries.No noise at night. How the circuit works As circuit diagram in Figure 1 Figure 1 the circuit diagram of the Solar plant watering alarm. Hand draw use AAx3 batteries 4.5V The main principle is that when the soil is dry, with high resistance. However, when the soil is wet with minimal resistance. Usually the wet soil will have resistance is about …
Simple temperature to voltage converter circuit
Meters & Detectors
This is a simple temperature to voltage converter circuit or an Electronic thermometer circuit there. Which will operate in a temperature range of 0 to 24 degrees Celsius (32 to 75 degrees Fahrenheit). The output rate of 500mV per degree Celsius. Which can be read by a normal voltmeter. To make it easier to find devices thus Temperature sensors of this circuit. So use a coefficient thermistor relatively constant and not linear. However, the temperature range of 0-24 degrees Celsius. This is enough to use a thermometer kind of normal. The IC1 is op-amp as the difference amplifier. There are …