Product Specification Sheet APS326

Rev. 08/2013

CB901 Series Central Exchange Unit

Typical CB901/XXX Central Exchange
Architects' And Engineers' Specifications

The central exchange/system shall be Alpha Communications® / Ring CB901 series or approved equivalent. System shall have a maximum capacity of 7200 total master and/or remote stations, in multiples of 8 stations. System shall have a minimum of (15) conversation paths (links), permitting up to (15) simultaneous conversations. The CB901 central exchange can be field upgraded with the addition of subscriber card(s) and required extension rack(s). Additional talk paths (links) are also available as an optional upgrade.

The CB901 system shall require simple 2 twisted pair home-run wiring from the central exchange to each master and/or remote station, and shall feature all-call, group call, hunt, priority, privacy, direct dialing, conference, camp-on busy, hurry-up, call-back, call-forwarding, secretary transfer, battery back-up and manual simplex override at the master station(s).

Optional features include radio paging, public address tie-in, 2 channels of program distribution, and emergency elevator annunciation.

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

CB901 Series Microprocessor Intercom System
The CB901 is a fully electronic, microprocessor controlled system, which fully satisfies the requirements for a modern and effective internal communication system. The CB901 system is modular in concept and the central exchange can be expanded in multiples of 8 stations, up to a maximum of 7200 total stations (masters and/or remotes). The central exchange has a minimum of 15 conversation paths (links), permitting up to (15) simultaneous conversations. More links can be added as an optional upgrade.

A variety of master and remote stations is available to meet virtually any system need.

  • Clear two-way communications
  • Hands-free/loudspeaking
  • Confidential/Softspeaking capabilities
  • Manual Simplex operation at master stations
  • Microphone Cut-Off
  • Camp-on busy extension
  • All-Call (standard)
  • Simple home-run wiring - simple to install
Power Required:
24VDC regulated
Internal Voltages:
+/- 12V, +/1 5V, 0V Power
Approx. 1 Amp plus 100mA per 8 station subscriber card. Maximum approx. 100 Watts Data unit approx. 1 Amp Cable
1 Pair for system information/audio 1 Pair for DC power supply
MC68000 (16 bits)
EPROM 512 kbyte RAM 384 kbyte
Ambient Temp:
+10 to +35 degrees C. (+77 to +95 degrees F.)
Line Specs:
Frequency Range: 300-5000 Hz
Galvanic Line: 0 dBm (1mW/600 ohm)
Speech level, idle: -12 dBm
Speech level, max: +4 dBm
Signaling level: -10 dBm
Signaling frequencies CCITT specifications
Pearl Grey
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.