Features: High Performance Broadband Seismometer Low Self-Noise Over a Wide Bandwidth Portable Design Low Power Consumption Force-Balance Electric Feedback Robust Mass Locking Mechanism Easy Installation Applications: Local and Regional Broadband Surface or Posthole Installation

The 151-60 Broadband Seismometer is a force-balance feedback sensor with frequency bandwidth 0.0166 Hz (60 sec) -50Hz flat to velocity. The 151-60 contains three independent sensors (one vertical and two horizontal) with built-in electronic feedback circuit, control and power conversion circuits, featuring low noise, large dynamic range and easy installation and use.

The 151-60 has a built-in leveling and mass lock/unlock facilities. The leveling mechanism includes two bubble levels, three adjustable feet and three locknuts which are located on the seismometer's chassis (see photo below).

The 151-60 has built-in mass zero-position adjusting mechanism to perform automatic mass adjustment. As soon as the seismometer is powered it checks the zero position of each component's mass and automatically adjusts the zero position if needed. Monitoring and adjustment of the mass can also be performed via the 130 family High Resolution Recorders using Sensor Control Board, RT527-B01.

The 151-60 is a low noise seismometer (see below Power Spectral Density plot). The low self noise performance makes the 151-60 an ideal seismometer for local, regional, and global seismicity studies in different installation configurations, including observatory and portable, surface and posthole applications.