Product Specification Sheet APS558

Rev. 07/2013

TT212 Speaker/Microphone Control Module

Architects' And Engineers' Specifications

The speaker/microphone and control unit(s) shall be Alpha Communications® / S.T.R.™ ReliaBUS™ model TT212 or equivalent. Unit(s) shall be powered by the model SP300 ReliaBUS™ controller. All wiring to power supply/amplifier shall be low voltage Class II wiring, installed as per all federal, state, and local electrical codes. 

TT212 shall be designed to mount directly into the 'TT' or 'TTM' series lobby entry panel stations. TT212 shall contain the speaker and microphone and memory circuits for up to 24 of the HT3011 handsets, all in one 'snap-in' assembly. Unit shall snap onto the panel front speaker/microphone grille. 

TT212 shall provide the intercom amplification and signalling control for the proper system operation. TT212 shall be installed a safe distance from any source of electrical interference. 

Contractor shall observe all local and national electrical and building codes.

TT212 Speaker/Microphone Control Module

These Alpha Communications® / S.T.R.™ TT212 ReliaBUS™ speaker/microphone control module is used with the HT3011 series ReliaBUS™ handset stations to provide intercom amplification and power to operate the associated intercom system, and certain optional components and/or accessories, such as electric door opener(s) etc. 

The TT212 is used in conjunction with the SP300 ReliaBUS™ controller. 

These TT212 speaker/microphone control modules are designed to easily mount right onto the plastic speaker/microphone grille in the 'TT' and 'TTM' series lobby entry intercom panels. 

The TT212 can accommodate up to 24 of the HT3011 ReliaBUS™ handsets, when used with conventional push-button type door station(s).

  • Easily Installs Right Behind Lobby Entry Panel
  • Operates on Safe Low-Voltage Class II Wiring
  • Clear Voice Fidelity with Adjustable Voice Volume Control
  • Convenient Screw Terminal Connections
2.375"W (61mm) x 5.25"H (134mm) x 1.50"D (39mm). 
Adjustable Volume Control (potentiometer) built-in
Positive Screw Terminal Connectors.
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Due to continuous product improvement, all colors, sizes, materials, finishes and specifications are subject to change without notice.