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WTB 4

Product information, applications, features, benefits, and brochure.

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WTB 4

WTB 4

Overview

The Wireless Trigger Box 4, or WTB 4, is a wireless trigger system for mechanical impact sources. It detects a source firing event and wirelessly triggers one or more seismographs using GPS timing and VHF radio communication.

A typical WTB 4 system uses two units. One WTB 4 connects to the source and detects the trigger pulse from a hammer switch or other impact device. A second WTB 4 connects to the seismograph, receives the source trigger message, and starts the recorder.

Each WTB 4 includes an internal Radio Trigger Module, 3 watt VHF radio, 99 watt-hour rechargeable battery, internal GPS, and standard Wi-Fi. The system supports flexible 2D and 3D layouts where one source can trigger multiple seismographs, or one recorder can receive trigger messages from multiple sources.

Features

Wireless Source Triggering
  • Wirelessly triggers seismographs from mechanical impact sources
  • Detects hammer switch or source trigger closure
  • Transmits trigger time and position from source to recorder
  • Supports multiple sources and multiple seismographs
  • Useful for 2D or 3D seismic configurations
Two-Unit System
  • Source WTB 4 detects the trigger pulse from the source
  • Recorder WTB 4 receives the source message
  • Recorder WTB 4 starts the seismograph
  • Source WTB 4 can trigger multiple WTB 4 equipped seismographs
  • Recorder WTB 4 can receive trigger messages from multiple WTB 4 equipped sources
Integrated Hardware
  • Internal Radio Trigger Module
  • Internal 3 watt VHF radio
  • Internal 99 watt-hour rechargeable battery
  • Internal GPS module
  • Internal Wi-Fi standard
Theory of Operation
  • Each WTB 4 acquires GPS lock using internal or optional external GPS
  • Source WTB 4 detects the falling edge of the source trigger signal
  • Source WTB 4 calculates GPS time of the event
  • Source WTB 4 transmits GPS time and position by VHF radio
  • Recorder WTB 4 triggers the seismograph exactly 1/2 second after the source trigger time
Specifications
  • Trigger signal: TTL or switch closure
  • Trigger input detects negative edge
  • Trigger output: TTL negative pulse
  • Radio cycle time: 500 milliseconds
  • Accuracy: ±1 microsecond
  • Radio: 3 watt
  • Radio range: 1 mile, or up to 3 miles with optional 1/2 wave antenna depending on terrain
Optional Features
  • Removable external memory backs up time breaks at the source
  • External GPS module for mounting GPS outside the source
  • 99.9 watt-hour Li-Ion internal battery
  • External 1/2 wave radio antenna extends radio range
  • Navigation App allows navigation and WTB 4 status viewing
Physical Specifications
  • Weight: 4.5 lbs / 2 kg with radio and battery
  • Size: 11.5 x 7.25 x 3.0 inches
  • Size: 292 x 184 x 76 mm
  • Runs up to 24 hours depending on use

Benefits

Trigger Without Cables
  • WTB 4 eliminates long trigger cables between the impact source and the seismograph, simplifying field setup.
Support Flexible Source Layouts
  • One source can trigger multiple recorders, and one recorder can receive trigger messages from multiple sources.
Improve Timing Accuracy
  • GPS event timing with ±1 microsecond accuracy provides reliable trigger timing for seismic acquisition.
Work Around Field Obstacles
  • Wireless VHF triggering helps crews operate across roads, rough terrain, vegetation, or areas where trigger cables are impractical.
Backup Critical Shot Information
  • Optional removable memory stores source GPS time and position for backup and later review.
Support Simple Impact Source Crews
  • WTB 4 works well with hammer switches, weight drops, and other mechanical impact sources used in near-surface seismic work.

Related Applications

Learn more about applications commonly used with this product.

Mechanical Impact Sources
  • Wirelessly trigger seismographs from hammer switches, weight drops, and other impact sources.
Near Surface & Engineering Seismic
  • Useful for MASW, refraction, and shallow seismic projects where wired trigger lines are inconvenient.
2D and 3D Acquisition
  • Deploy multiple source and recorder systems in flexible 2D or 3D configurations.
Remote Triggering
  • Use VHF radio triggering where the source and recorder are separated by terrain or field obstacles.
Weight Drop Acquisition
  • Trigger DAQlink, GeoDAQ, or other seismographs from accelerated weight drop systems.

Brochure

WTB 4 Brochure