The ML3 ThetaKit provides researchers with a portable tool for highly accurate, near instantaneous measurement of moisture levels in soils and substrates. 

The ThetaKit is easy to use. Simply switch the connected HH2 Moisture Meter on, insert the probe pins fully into the soil, and press the HH2’s “read” button to display the moisture measurement. Readings can then be stored with a single button press (if required) – and downloaded to PC later.

The kit comprises an ML3 ThetaProbe Soil Moisture Sensor, an HH2 Moisture Meter (readout unit), replacement sensor rods, and a carry case

Measurement	Volumetric water content and soil temperature
Accuracy	± 0.01 m3.m-3 (1%)  With soil-specific calibration
	± 0.5°C (0 to 40°C for temp sensor) ± 0.75°C (-20 to +60°C for temp sensor)
Soil moisture measurement range	Full accuracy over: 0 to 0.5 m3.m-3
	Full range : 0 to 1.0 m3.m-3
Salinity range	50 to 500 mS.m-1
	Salinity errors < 0.035 m3.m-3 from 0.05 to 0.4 m3.m-3. Can be calibrated up to 2000 mS.m-1
Temperature range	Full accuracy over: 0 to 40°C
Output	0 to 1.0 V differential Corresponding to 0 to ~0.6 m3.m-3
	Resistance 5.8Ω to 28Ω for temp sensor
Power requirement	5-14 V, ~18 mA for 1s
	Minimum 5.5 V with 100 m cable
Environmental	IP68 (-40 to +70°C)
Sample volume	~60 x 30 mm diameter
	Sample volume is weighted towards soil immediately surrounding the rods
Dimensions and weight	Overall: 158 x 40 mm diameter  Rods: 60 mm x 3.2 mm diameter  (Rods are replaceable) Weight: 0.1 kg (exc. cable)
Sensor calibrations	Individual sensors are interchangeable Recalibration advised every 3 years (depending on use)
Soil calibrations	Generalised Mineral and Organic soil calibrations are supplied

HH2 Meter

Input connections	1 water content sensor or 1 WET Sensor
Control outputs	–
Readings stored	1,500
Recording rate	–
Configuration	By keypad
Communication options	RS232 / USB [1]
Sensor excitation	1 switched battery
Power	1 9V 6LR61 (PP3)alkaline
Battery life (dependent on usage)	~ 5,000 readings
Enclosure rating	IP54
Temperature range	0 to +40°C
Display	2 line x 16 character
Size	125 x 80 x 45mm
Typical applications	Instantaneous reading of soil moisture / profiles/ WET Sensor

Channel science and technology has been dedicated to the teaching, scientific research and the sales, research and development of applied instruments in the fields of soil, plants, environment, hydrology, meteorology and animal physiology, ecology and environmental hydrology for many years.