Product Specification Sheet APS217

Rev. 07/2013

SDR-113 Sound Detection Relay Board

This Specsheet is for a product which is discontinued. Please contact us for alternative products.
  • Audio surveillance monitoring
  • Advanced audio threshold detection
  • Three levels of discrimination
  • Automatic compensation for ambient noise
  • Annunciates on master or remotely
Architects' And Engineers' Specifications

The Sound Detection Relay shall be Alpha Communications® / Stento model SDR-113 or approved equivalent. The housing of the relay shall be a steel card cage that handles up to 25 SDR-113 boards. The model SDR-R25 allows field hook-up via rear panel mounted Euro style connectors. The unit shall contain six (6) (3 audio and 3 logical timing) potentiometers. The unit requires a 24 VDC power supply.

The SDR-113 shall operate on all 9600 series intercom systems.

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

SDR-113 Sound Detection Relay
The Alpha Communications® SDR-113 Sound Detection Relay Board uses 9600 series remote substations to monitor any area for unusual sound or disturbances. Six (6) adjustable potentiometers allow unique flexibility. The trigger level varies automatically as ambient noise levels increase, or decrease, eliminating the need for day/night switches. Sudden loud noise above ambient noise levels such as screams, gunshots, or breaking glass can easily be detected and annunciated on a red LED on the 9600 series master. Selecting the appropriate station button on the master allows the are to be monitored and provides relay contacts for external alarms and annunciation. The SDR-113 will operate on all 9600 series intercom systems.

Steel card cage handles up to 25 SDR-113 boards. Model SDRR25 allows field hook-up via rear panel mounted Euro style connectors
5.25" H x 19.00" W x 5.00" D (134mm) x (483mm) x (127mm)
Low level 45 ohm intercom speaker
Max Gain:
Ambient, 100 dB; detector, 106 dB
Dynamic Range:
More than 40 dB
Timers: Discriminator : adjustable 0.1 - 1.1 seconds
Window: adjustable 2.4 - 24.2 seconds
Extended: adjustable 11.0 - 33.0 seconds
6 trimpots, gain, ambient level, filter level, discriminator timer, window timer, extended timer
24VDC 50 mA maximum for each SDR-113 board
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.