10HS
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ABOUT THE 10HS
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About the 10HS
The 10HS measures the dielectric constant of the soil in order to find
its volumetric water content (VWC). Since the dielectric constant of
water is much higher than that of air or soil minerals, the dielectric
constant of the soil is a sensitive measure of volumetric water content.
The 10HS has a low power requirement and very high resolution.
This gives you the ability to make as many measurements as you
want (i.e hourly) over a long period of time with minimal battery
usage.
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Background Info
In 2005, the Decagon research team optimized a sensor oscillator fre-
quency for very high accuracy soil moisture measurements. The first
sensor to incorporate the new frequency was our EC-5 sensor. The
EC-5 quickly became Decagon’s most popular soil moisture sensor.
The new 10HS sensor uses the same 70 MHz oscillator frequency
as the EC-5, but has a larger soil volume and requires no special
calibration when you use it with other systems. The 10HS has two
features that distinguish it from the EC-5.
•
The on board voltage regulator allows you to power the sensor
with a wide range of excitation voltages (3 to 15 VDC) without
changing the calibration.
•
Large sensing area (1,100 cubic centimeters) that provides a
more representative measurement of soil VWC.
The 10HS sensor runs at the same oscillator frequency that has given
the EC-5 exceptional performance in soils (Kizito et.al, 2008, Bogena
et. al, 2007). We recommend the 10HS sensor for mineral soil appli-
cations where soil heterogeneity is a concern. However, we continue
to recommend the smaller EC-5 sensor for soilless substrate appli-
cations or applications where VWC measurements on smaller scales
(e.g. near surface measurements, laboratory column studies, green-
house applications) are desired.
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