The 151D Bronco Broadband Seismometer is an observatory grade force-balance feedback velocity sensor available with the frequency bandwidth of 0.0083 Hz (120 sec) - 50 Hz. The seismometer contains three independent symmetrical sensors arranged in an orthogonal Galperin configuration. The sensor signals are deconvolved to provide the traditional ZNE orthogonal seismometer output for low noise and large dynamic range measurements.
The 151D Bronco has built-in leveling and automated mass lock/ unlock features for ease of installation. The leveling mechanism includes a single bulls-eye bubble level, three adjustable feet and three locknuts. Sensor mass will automatically unlock upon application of power to the sensor, and relock when power is removed. Upon unlocking the sensor a mass zero-position adjusting sequence will perform automatic mass zero adjustment if needed.
Recording of signals, along with monitoring and adjustment of the mass and sensor can also be performed via the Reftek Wrangler High Resolution Seismic Recorders using the sensor control interface of the 151D. The 151D Bronco is an exceptionally low noise seismometer (refer to the Power Spectral Density plot). The low self noise performance makes the 151D an ideal seismometer for local, regional and teleseismic seismicity studies in different installation configurations.