MA-485A Intercom Ampliﬁer
The MA-485 ampliﬁer provides audio ampliﬁcation, control and power needed to operate an apartment intercom system. Extensive tests were performed to develop a reliable, long lasting intercom ampliﬁer with precision ampliﬁer circuits to provided crystal clear audio reception. Mircom’s ampliﬁer uses an automatic level control (ALC) circuit to ensure voice intelligibility. Built-in features include: timed door release silent door release and post ofﬁce release.
A site station in each apartment allows the tenant to be called from and converse with the visitor in the vestibule. A visitor presses the appropriate call button to transmit a call tone through the suite station. The tenants answer the call by alternately pressing the ‘Talk’ and ‘Listen’ buttons to converse with the visitor. After verifying the visitors identity, the tenant may admit the visitor by momentarily pressing the button marked “door” which triggers the electric door strike.