The Thelma Biotel Focus – Directional amplifier field kit is an acoustical reflector which slips over the standard Live transceiver. It is delivered with a telescopic boompole which screws into the 1/4″ camera mount thread on the Live. With the Focus, the amplification of signals is strong around +-15 degrees in reference to the target. Outside of 60 degrees from the target, the signal becomes weak or completely muted. The kit is designed to be used with the DeckBox to increase the range and to provide a bearing for the direction of an acoustical transmitter. You need this kit to increase the safe distance of communication when working with the TBR 800 Release – Deep version. We suggest you use the Focus kit for all Release receivers deeper than 200m.


  • Designed to be used with DeckBox field kit
  • Acoustic reflector to slip over standard Live transceiver
  • Provides the direction of acoustic signal targets
  • Amplifies acoustic signals for increased range


  • Communication with receivers deployed on deeper locations
  • Communication with receivers in challenging conditions
  • Compass bearings of deployed receivers or gear
  • Bearing of fish tags