The small, precisely defi ned 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. Equipped with a direct burial connecting cable, the Hydra Probe allows for data collection over a large study area in a variety of soil conditions.

The data reduction algorithm converts analog voltages to the following outputs: the real and imaginary dielectric constant, temperature, temperature corrected real and imaginary dielectric constants, water content, soil salinity (indicative of nitrate levels), soil conductivity, temperature corrected soil conductivity and temperature corrected soil water conductivity.

The provided data reduction program can operate on a PC or Smart Logger fi le of raw sensor input data, and output a fi le consisting of processed data, or the program performs the data reduction algorithm on the data in an ASCII fi le download format from Stevens hand held data reader.

A rugged design with all internal components potted for a robust, zero maintenance design makes the Hydra Probe ideal for remote and environmental hostile conditions. This durable construction makes it possible for the unit to remain in the fi eld for many years, maintenance free.

• Simultaneously measures:
  • Soil moisture
  • Soil salinity
  • Soil temperature
• Instantaneous sensor response
• No calibration requirements
• Compact, rugged, no maintenance design
• The dielectric constant, soil moisture, and conductivity accuracy measurements are improved using 1 of 3 soil calibration constants
• Compatible with most data logging systems with multiple analog inputs

Long-term monitoring or spot checking of soil moisture, conductivity, and temperature for:

• Irrigation management
• Geotechnical studies
• Weather/climate studies
• Watershed management
• Flood control forecasting

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.