Stick the metal probes into a freshly watered plant and adjust R5 for a mid-scale meter deflection. The meter will monitor the soil wetness and the meter will indicate whether it is to moist or to dry. This circuit uses a dual power supply which could be created by two 9 volt batteries.
Source : http://home.maine.rr.com/randylinscott/nov20.htm
Related Links
Plant moisture meter
Soil moisture meter
LM741 circuits
Moisture Activated Relay by Bipolar Transistor
Soil Moisture Meter
Metal Detector Circuit by BC548
Dew sensor by LM358
Moisture Meter by 2N2222
Plant moisture level monitor
This entry was posted on Friday, April 27th, 2007 at 9:25 am and is filed under 741, basic electronics, meter.
