The ALPHA-TAD120-LIGHT is a three component low noise feedback, DIGITAL OUTPUT velocity broadband seismometer designed by Dr. C.M. Güralp. In the 1970's and 1980's Dr. Güralp set out the standards for miniature surface and borehole broadband seismometers.
The Broadband Feedback seismometer is based on orthogonal three axis low noise sensor modules with double nested feedback loop topology. The suspension system is based on the principles of “elastica”. The mechanical sensor orientation is Non-Galperin with -75 dB cross axis rejection on all axis.
The ALPHA family of sensors are three component low noise feedback velocity output Broadband seismometers suitable for local, regional and teleseismic recording.
- Single or large scale seismic networks
- Micro-seismic monitoring
- After-shock monitoring
- Hydrocarbon exploration
- Permanent reservoir monitoring
- Induced seismicity detection
- Explosion monitoring
- Post-hole seismology
- Micro-seismic monitoring
- High quality digital broadband data
- Covers the complete seismic spectrum with a single transfer function
- Particularly low noise at high frequencies compared to other broadband sensors
- 8-Channel 24-Bit internal digitiser
- Programmable Gain Amplifiers on all channels
- Remotely configurable and controls sensor functions
- Automatic centring based on mass position offset
- Suspension system with high cross axis rejection
- Broadband data with a high frequency response extending to 150 Hz,
- Automatic self-installation and zeroing for quick installation
- Tilt tolerance of ±5 degrees
- Portable and easy to deploy
- Waterproof casing with connectors mated
The sensor frequency response covers the complete seismic spectrum with a flat frequency response (no peaks) from 0.008333 Hz (120 seconds) to 150 Hz.
A precision 24-bit 8-channel digitiser is housed inside at he waterproof enclosure.
The sensor noise level crosses (below) the New Low Noise Model (NLNM) from 18 Hz to 50 seconds period.
A truly portable rugged seismometer with fine pitched adjustable feet manufactured from phosphor bronze.
The sensor can be operated with ±5.0 degrees of tilt, and microprocessor controlled remote centring is provided.
Remote electronic mass lock and unlock facility, with a serial interface for sensor control and parametric sensor data.
Galvanically two stage isolated electronics. The sensor mechanical section and the feedback electronics sections have their own isolated and hermetically sealed enclosures.
The electronic and the mechanical sections of the sensor can be physically separated for observatory applications.
All outputs and digital inputs are transient protected.