Product Specification Sheet APS253

Rev. 07/2013

AA903 Brushed Aluminum Master Station (RM5000EX / CB901EX Series)

This Specsheet is for a product which is discontinued. Please contact us for alternative products.
Architects' And Engineers' Specifications

The master station(s) shall be Alpha Communications® / Ring model AA903 or approved equivalent. Master(s) shall have clear two-way communications. Master(s) shall feature a 12-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 BBF903 (flush backbox) or BBS903 (surface metal back box) or BF936 (surface plastic 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.

AA903 Flush (or Surface) Mount Master Station

The AA903 is designed for normal use as a flush-mounted unit with a metal back-box (BBF903). However, the station will also fit into a (BBS903 metal or BF936 plastic) back-box for surface 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 section contains a warning lamp and 12 buttons plus a privacy switch, which also functions as a microphone cut-out switch when pressed during a conversation.

On the touch-dial keyboard, the left-hand T-button is provided for manual control of a conversation when desired. The X-button is used to cancel a call. An optional model no. GD591 add-on handset is also available.

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
  • Intersystem mobile radio interface
  • Alarm and program distribution

Color: Brush Aluminum Faceplate
Dimensions: 3.9" (115mm) W x 10.6" (270mm) H
Operating Voltage:
24V DC+/- 20%
Power consumption:
approx. 5W
Frequency range:
300 - 5000 Hz 
Galvanic line:
0 dB (1 mW/600 ohm) 
Speech level: 
normal -12 dBm, max + 4dBm
Tone signalling:
according to CCITT norms 
Loudspeaker impedance:
50 ohms 
Mounting: Flush Backbox: BBF903
Surface  Backboxes: BBS903 (Metal) / BF936 (Plastic)
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.