What portion of the communications model could be defined as the translator?

The receiver is responsible for decoding and interpreting the message after it arrives, not for translating it during transmission.

The medium functions as the translator in the communications model because it carries and converts the message from the sender's encoded format to the receiver across a communication channel. It bridges the encoding performed by the sender and the decoding performed by the receiver, transforming the message for transmission. Examples include email, voice, and written documents - each of which translates intent into a transmittable form.

Translator is not a formally defined component in the standard communications model - the translation function is fulfilled by the medium.

The sender is responsible for encoding and originating the message, not for translating it as it travels through the channel.