Abstract: An electret microphone assembly in which an insulating support disposed between the apertured front and back walls of a conductive housing has an enclosed portion contained in the housing and an exposed portion extending out of the housing through an opening formed in the side wall thereof. The support carries the back electrode of an electret microphone on the front of the enclosed portion and an FET amplifier circuit on the back of the same portion. Respective electrical contacts formed on the back of the exposed portion of the support extend inwardly through the side opening in the housing to provide external connections to the source and drain of the FET and to the amplifier common line.

Abstract: A hand-held microphone assembly for use with two-way communications equipment in which an electret-capacitor microphone is mounted in the upper surface of the barrel portion of a pistol-shaped casing. A push-to-talk trigger disposed at the end of the barrel actuates a double-pole, double-throw slide switch to couple the output of a local preamplifier in the casing to an audio output line leading from the casing and to make suitable couplings between three changeover lines. A resilient conductive strip disposed within the casing at the inner end of the slider element is actuated in response to the operation of the double-pole switch to couple the preamplifier to a normally disconnected amplifier power supply in the casing.