The Stevens Hydra Probe performs high frequency electrical measurements of the capacitive and conductive properties of sand, silt, clay and loam soil which are directly related to simultaneous measurements of:

• Soil moisture
• Soil electrical conductivity
• Soil temperature

The Hydra Probe's precisely defined sensing area allows accurate measurements in regions where there are strong soil moisture gradients, such as near the soil surface. Response time is immediate to changing soil moisture conditions, and no calibration is required.

Applications include:

• Weather / Climatological monitoring such as performed by the USDA NRCS National Water Climate Center
• Research studies
• Water shed management
• Agriculture irrigation monitoring and control
• Golf course greens (installations include major golf courses such as Augusta)
• Sports Turf
• Wine vineyards

Analog Hydra Probe Data Reduction Programs
The following are software programs for viewing the Hydra Probe measurements. Please see the user manual for more detail information on these programs.

The HYD_FILE.EXE version 2.8 (for analog Hydra Probe only) software program is designed to operate on a PC file of raw input data, and output a file consisting of the processed data. This program is primarily designed to allow the user to quickly process large amounts of data from automated data collection systems. Please download the Hyd_file instruction manual for directions on how to use Hyd_file.

The HYDRA.EXE (for analog Hydra Probe only) data reduction software program enables user to manually convert four voltages to complex soil moisture reading. HYDRA.EXE will prompt the user for a soil type and the four measured voltages V1, V2, V3, V4s. The program will then generate the following output, real and imaginary dielectric constant, temperature, temperature corrected real and imaginary dielectric constants, water content, soil electrical conductivity and temperature corrected soil electrical conductivity.