High Frequency

  Salient Features: This 3-channel sensor has a frequency of 4.5Hz, is critically damped at .707 and has a sensitivity of 32 V/m/s. Used for (but not limited to) active source (land and off-shore excitations), glacial movements, local earthquake and aftershock studies. Manufacturer Website: http://www.geospace.com/ PASSCAL Documents: Connector wiring information here Installation & Troubleshooting Documents: Y-28 Orientation and Installation Tips here One-pager field sheet

PASSCAL Passive High-Frequency Sensors: 4.5 Hz 3-channel geophones (Sercel L-28-3D or GeoSpace Y-28/GS-11-3D) 4.5 Hz vertical geophones for Texan or Multi-Channel Digitizers 40 Hz vertical geophones for Texan or Multi-Channel Digitizers See also All-In-One Systems (Fairfield Nodes, SmartSolo) Features:

Salient Features:

PASSCAL owns two types of 40Hz vertical geophones.

The 40Hz geophones for the Multichannel Digitizer Systems are manufactured by Sercel and Geospace.  These vertical geophones are critically damped at 0.555 and have a sensitivity of about 21 V/m/s. The 40Hz geophones for the Texan Digitizers these geophones are manufactured by Sercel.  These vertical geophones are critically damped at 0.555 and have a sensitivity of 35.3 V/m/s

Uses primarily include active source studies.

Salient Features These single component geophones are available as vertical units for use with the Texan digitizer and as vertical 6-channel strings for use with the multi-channel digitizer systems.  The multi-channel strings are rarely used. This single channel vertical geophone has a frequency of 4.5Hz, damping of .707 critical and a sensitivity of 100 V/m/s. The primary use of these geophones is for active source experiments. Manufacturer Documents: PASSCAL’s 4.5Hz, vertical geophones were manufactured by Geospace under part number GS-11D. Installation & Troubleshooting:

 Installation requires a separate bubble level to be placed on top of the geophone for proper leveling.

  Salient Features:  This 3-channel sensor has a frequency of 4.5Hz, is critically damped at .707 and has a sensitivity of 30.4 V/m/s.  Used for (but not limited to) active source (land and off-shore excitations), glacial movements, local earthquake and aftershock studies. Manufacturer Documents  http://www.sercel.com/products/Lists/ProductSpecification/Geophones_brochure_Sercel_EN.pdf

Download the Brochure to obtain information about the L-28 geophones.