Safety transceiver inside safety helmet - has frame antenna built into helmet and microphone and switching unit underneath front projection

摘要

The transceiver is a safety arrangement for radio signals transmission in mines tunnels etc. At least one frame antenna (2) is provided on the helmet's (1) inner side. It consists of a coil fitting into the helmet's inner surface. Receiver section (3) with at least one receiver and a sender section (4) with at least one sender are mechanically fastened inside the helmet. The transmitter and receiver are connected by wires to a microphone, a switching unit with a switch (61), earphones (7) with holders (8) and a power source. All functional parts are inside the helmet and are therefore protected.