Product Specification Sheet APS666

Rev. 11/2013

AA903C Brushed Aluminum Master Station (RM5000EX / CB901EX Series)

Architects' And Engineers' Specifications

The master station(s) shall be Alpha Communications® / Ring model AA903C or approved equivalent. Master(s) shall have clear two-way communications. Master(s) shall feature a 16-button keypad, and shall require simple home-run wiring. Master(s) shall be flush or surface wall mounted using the appropriate backbox/housing. Master(s) shall be used with the BBF863 (flush backbox) or BBS863 (surface back box) or BBD905 (desk backbox). Unit shall be finished in a brushed aluminum finish.

Master(s) shall be used with the RM5000EX and/or CB901EX series microprocessor intercom systems.

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

AA903C Flush (or Surface) Mount Master Station

The AA903C is designed for normal use as a flush-mounted unit with back-box model BBF863. However, the station will also fit into a model BBS863 back-box for surface mounting, or a model BBD905 for desk mounting.

The unit features a brushed aluminum front plate with speaker and microphone for normal hands-free speech with a range of approximately 3-5 meters or 10-15 feet. Its keyboard consists of 10 numeric dialing buttons (DTMF), Push-to-Talk button (T), Cancel button (X), Volume Up/Down buttons, Privacy button (P) and a microphone Mute button (M). A status LED is used for indicating station-ON and Privacy.

An optional add-on handset connector is included, for use with the optional model GD501 privacy handset.

The station permits the connection of a parallel speaker where additional output is required (loudspeaker impedance 50 ohms recommended). The station is designed to work with the RM5000EX and/or CB901EX series microprocessor intercom systems.

  • Clear two-way communications
  • Total privacy with warning tone
  • Discreet call mode
  • Ringing tone / Voice insert
  • Microphone cut-out / Conference
  • Remote control circuits (doorlocks, bells etc.)
  • Automatic busy call-back
  • Hurry-up tone
  • All/Group calls with reply-back
  • Automatic call redirection
  • Secretary transfer
  • Group hunting / Priority
  • Speed dialing
  • Status LED
Color: Brush Aluminum face plate
Dimensions: Width: 5.25" (134mm)
Height: 9.50" (242mm)
Flush Depth: 1.60" (40mm)
Operating Voltage: 20-27VDC
Power Consumption: approx. 150 mA max.
Frequency Range:
300 - 5000 Hz
Galvanic Line:
0 dB (1 mW/600 ohm)
Speech level:
max + 4dBm
DTMF Signaling: -10 dBm
Flush Backbox: BBF863
Surface Backbox BBS863
Desk Backbox BBD905
Alpha Communications
42 Central Drive • Farmingdale • NY • 11735-1202 • Phone: (631) 777-5500 • Fax: (631) 777-5599
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Due to continuous product improvement, all colors, sizes, materials, finishes and specifications are subject to change without notice.