Manufacture complete vibration test systems including shock and vibration controllers, electrodynamic shakers, head expanders, power amplifiers , transducer calibration systems and instrumentation.Unholtz-Dickie Corporation - Vibration Test Equipment Unholtz-Dickie Corp. General Information Specializing in the design and manufacture of complete Vibration Test Systems, including Electrodynamic Shaker Systems, Shock and Vibration Controllers, Horizontal Slip Table Assemblies, Long Stroke Thrusters, Head Expanders, Power Amplifiers, Transducer Calibration Systems, Accelerometers and Instrumentati