|Each element consists of a housing
that contains a dynamic earphone transducer and a foam earplug tip. The
transducer is directly connected into the communications system through a
small, highly flexible coaxial wire with overall diameter of less than
1.6 mm (0.063 inches). Outer covering of the wire will be polyurethane
to reduce hardening effects caused by contact with various chemicals.
The construction of the wire uses an alloy that is designed to reduce
flexure breaks, extending the life of the product.
foam earplug tip provides sound attenuation for the user when fit into
the ear canals. The earplug tip has an internal threaded insert that
extends through the center from the base to near the tip and mates with
the threaded adapter on the transducer housing. The speech signal
produced by the transducer is directly coupled into the occluded portion
of the ear canal through the 1.3-mm (0.051-inch) channel in the
threaded adapter and foam earplug tip.
CEP unit is connected into the helmet communications circuit through an
SMB type connector. The CEP-helmet-interface consist of a mating SMB
coaxial recessed bulkhead jack receptacle that is connected, via 254 mm
(8 inch) length of RG-174 coaxial cable, to the communications circuit
inside the right earcup. The CEP-helmet-interface connection to the
communications circuit includes a voltage divider network that adjust
the speech output sound level at the ear to similar levels produced by
the HGU-56/P helmet. Modifications will not reduce the sound attenuation
characteristics of the helmet when worn alone or affect the speech
output level of the helmet earphone earcup system.