The TDR100 Time-Domain Reflectometer is the core of the Campbell Scientific Time Domain Reflectometry system. The TDR100 (1) generates a very short rise time electro-magnetic pulse that is applied to a coaxial system which includes a TDR probe for soil water measurements and (2) samples and digitizes the resulting reflection waveform for analysis or storage. The elapsed travel time and pulse reflection amplitude contain information used by the on-board processor to quickly and accurately determine soil volumetric water content, soil bulk electrical conductivity, rock mass deformation or user-specific, time-domain measurement.
Up to 16 TDR100s can be controlled using a single Campbell Scientific datalogger. A 250-point waveform is collected and analyzed in approximately two seconds. Each waveform can have up to 2,048 data points for monitoring long cable lengths used in rock mass deformation or slope stability. Averaging up to 128 makes accurate measurements possible in noisy environments.
Features
- Compact, low-cost reflectometer
- Designed for use in remote applications
- Determines volumetric water content and electrical conductivity in soil and other porous media
- Can be used in rock-mass deformation applications
- Communicates with SDMX50-series coaxial multiplexers using our SDM protocol
- To control the TDR100, the CR10X and CR23X use Instruction 119 and the CR800, CR850, CR1000 and CR3000 use the TDR100 instruction.
- The CR10X operating system (OS) should be version 1 rev. 13 or higher and the CR23X OS should be version 1 rev. 10 or higher.
- All CR800, CR850, CR1000, and CR3000 operating systems (OS) are compatible with the TDR100.
Specifications
- Pulse generator output: 250 mV into 50 ohms
- Output impedance: 50 ohms ±1%
- Timing resolution: 12.2 picoseconds
- Waveform averaging: 1 to 128
- Temperature range: -40° to 55°C
- Dimensions: 21 cm x 11 cm x 5.5 cm (8.3” x 4.3” x 2.2”)
- Weight: 700 g (1.5 lbs)
