About MOHR

Test and Measurement

MOHR develops and manufactures a number of innovative test and measurement technologies:

Test Equipment

  • CT100 Series Time Domain Reflectometer (TDR) Cable Testers
  • MDT Series Agricultural Penetrometers

Process instrumentation

  • EFP Series Guided UWB Radar Liquid Level Sensors
  • EFP-RD-UPS Instrumentation Power Supplies / Battery Backups


MOHR is an Independent Software Vendor. We develop several different packaged software solutions targeting Microsoft® Windows® desktops and Windows® Mobile:

Desktop software products (targeting Windows® 7 and newer)

  • MDT Desktop
  • CT Viewer 2
  • EFP Desktop

Embedded software products (targeting Windows® Mobile)

  • EFP Series Applications
  • CT Series Applications
  • MDT Series Applications

Consulting Services

MOHR offers a range of application engineering consulting services:

  • Mechanical Engineering
  • Electrical Engineering
  • Software Engineering

Company History

Dr. Charles Mohr was project manager of the U.S. Nuclear Regulatory Commission's (NRC) large-break loss-of-coolant-accident (LOCA) experiments carried out in the National Research Universal (NRU) reactor at Canada's Chalk River National Laboratory from 1978-1983. These comprehensive experiments were designed to study mechanical deformation, flow blockage, and coolability during heatup, reflood, and quench phases of a large-break LOCA (NUREG/CR-1882, NUREG/CR-1208) and involved extensive instrumentation of 32 full-length (12 ft.) nuclear fuel rods. Time-domain reflectometer (TDR) liquid level probes developed by Dr. Mohr were a key component of the test train instrumentation package (NUREG/CR-3272).

Following the series of successful LOCA experiments at the NRU facility, MOHR was founded in 1983 with NRC financial support to continue development of reactor safety instrumentation. MOHR subsequently developed Electric Field Perturbation (EFP) technology, an ultrawideband (UWB) guided-radar technology that addresses the weaknesses inherent in existing guided-radar / TDR-based instrumentation. EFP Series instruments are the industry's only multiphase flow sensors designed to provide real-time estimation of total liquid coolant inventory and coolability within boiling water (BWR) and pressurized water (PWR) nuclear reactors, and can be used in a wide range of industrial applications for precision multiphase liquid-level, void-fraction, and volume-fraction monitoring.

The CT100 Series Automated Metallic TDR Cable Tester family was developed in response to an industry need for a portable high-resolution TDR instrument optimized for cable and wire testing. The CT100 TDR is in use by multiple U.S. national labs, numerous aerospace and defense technology companies, and has been selected by the U.S. Navy for its General Purpose Electronic Test Equipment (GPETE) program. The CT100 was designed to support a variety of Navy and Marine Corps applications, replacing the discontinued Tektronix(R) 1502B/C TDRs.

Development of the MOHR TDRs has continued, first with the release of the more advanced CT100HF and then in 2016 the release of the CT100B. MOHR continues to improve the world's finest portable TDRs.

In the late 1990's, the CEO of a major Washington State fruit-packing cooperative contacted Mohr and Associates about the need for an accurate, repeatable way of measuring fruit maturity to improve industry-wide fruit quality and competitiveness with emerging foreign agricultural markets. This led to the development of the Mohr Digi-Test (MDT) line of fruit penetrometers and texture analyzers, the first and only instruments to accurately characterize the internal structural maturity of apples and other tree fruit. The incorporation of this technology into the barcode-driven relational database model designed into the MDT Server software stands to revolutionize QA/QC within the tree fruit industry. The MDT-1 and MDT-2 instruments are in use by both industry and academia.

Our home office is in Richland, WA, a town near the Hanford reservation that was one of the original boomtowns of the Manhattan Project of WWII. Richland has extensive local scientific and engineering resources, including the Hanford nuclear reservation, dozens of related companies, and the Pacific Northwest National Laboratory(PNNL). Richland is situated along the Columbia River, near hundreds of thousands of acres of tree fruit orchards and vineyards supplied by the plentiful irrigation.