Product Specification Sheet APS256

Rev. 07/2013

AA905B / AA905C St. Steel Master Stations (RM5000EX / CB901EX Series)

This Specsheet is for a product which is discontinued. Please contact us for alternative products.

Model AA905B Shown

Architects' And Engineers' Specifications

The master station(s) shall be Alpha Communications® / Ring model AA905B (surface) or AA905C (flush) or approved equivalent. Master(s) shall have clear two-way communications. Master(s) shall feature a 12-button keypad, ultra-sensitive electret microphone, hands-free voice operation and shall require simple home-run wiring. Master(s) shall be surface wall mounted (model AA905B) or flush mounted (model AA905C) using the BBF863 flush  backbox/housing. Unit(s) shall be finished in a stainless steel finish. Units may be used directly outdoors and are designed to operate in a temperature range of  minus 20 degrees to plus 50 degrees Celsius. Both models may be used with the optional (model GD519) privacy handset, for confidentiality or softspeaking, where required.

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.

AA905B Surface and AA905C Flush Light Industrial Master Stations
Model AA905C Shown

The AA905B (surface) and AA905C (flush mounted) light industrial master stations are compact splash and dust resistant units. They are tested for internal or external use in temperatures from minus 20 degrees to plus 50 degrees C. The inside electronic parts and circuit board is specially treated with anti-corrosive lacquer, protected by a plastic housing and mounted in a stainless steel cabinet. Both models are fitted with vandal-resistant locking screws. Both models are complete with built in microphone and speaker, and an aperture is provided for the cord from an optional (model GD519) handset, when required. 

The front plate features the normal 12-button keypad of an AA916.

Both units are designed to work with the RM5000EX and/or CB901EX series microprocessor intercom systems.

  • Handsfree/loudspeaking
  • Confidential/softspeaking with optional handset
  • Conference
  • Hurry-up tone
  • Call-back / Call transfer
  • Remote control circuits (door locks etc.)
  • All/Group-call with reply back
  • Priority
  • Call forward/Secretary transfer
Depth 1.7" (42mm) 
1.6" (40mm)
Width 3.0" (72mm)
5.5" (140mm)
Height 7.9" (200mm)  9.9" (250mm)
Operating Voltage: 24V DC+/- 15%
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
External Loudspeaker impedance: 50 ohms
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.