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The AM-6747/V is an fully upgraded and improved version of the amplified loudspeaker AM-4979/GR. The speaker was designed for use with cryptographic equipment and can be easily employed with any radio. The design is water proof and features a mounting bracket as part of the enclosure. A 4 inches, 2 Watts, 8 Ohms permanent magnet cone type speaker, type LS-445/U is employed and input to the amplifier stage is of high impedance. The enclosure also includes a built in U-183/U audio connector for the addition of a microphone or handset. Complete isolation of the keying circuit (PTT) is provided by a relay. Internally, the AM-6747/V incorporates an audio amplifier and support circuitry. The audio input connection is achieved by the use of a enclosure mounted MS-3114E10-98S connector. A user provided cord with the proper terminations is required. DC power is supplied via an MS-3114E8-4S connector which is coupled with an appropriate cable assembly. The CX-12925/U cable can be employed to power the unit. The amplifier will not provide sidetone to the speaker during the transmit cycle and is muted by the internal relay. With a simple circuit modification, it is possible to provide sidetone during transmit.