The RT-B77 HELB is currently the most advanced and most powerful PLB available on the market for MOB emergencies. The RT-B77 is designed for automatic activation upon contact with water or inflation of the wearer’s life jacket and can also be activated manually.

This PLB also features a second frequency that can be used for testing or training purposes. Transmission of a dedicated ID and simple control of system and maintenance data by means of an IrDA interface are important benefits for operators of larger fleets. Autotest functions and status reports are announced by the system's speaker to guarantee high availability.
Special Features

Very high output power
Designed for use under adverse conditions
Extremely compact, lightweight design
High efficiency RF amplifier technology
Water resistant up to 50 m for diving applications
Automatic activation upon contact with water (can be disabled)
Programmable beacon ID for transmission
Functional and operating status by LED and built-in speaker
Voice output at RF and speaker
PLL design for free selection of training frequency
Microprocessor controlled power management for long battery life

Technical Data


width x height x depth: 75 mm x 103 mm x 27 mm



Operating temperature

-20 °C ... +55°C

Ingress protection

Water resistant up to 20m

Operating frequency

121.500 MHz (VHF)

Training frequency

Preselectable (in 25 kHz increments between 120.000 and 125.000 MHz)

Output power

2 W*


A3X and ASK
FSK (on request)

Battery type

2 x 9 V block LiMnO2

Battery life

6h to 48h*


IrDA and RS232


260 mm monopole antenna
90° and 180° monopole antenna for variable integration to life-jackets


KNRM Netherlands

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Nederlands Loodswezen B.V.

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