Product Specification Sheet APS647

Rev. 07/2013

VVDTMF DTMF to RS232 Decoder Board (for AlphaEntry™)

Architects' And Engineers' Specifications

The DTMF to RS232 Decoder Board(s) shall be Alpha Communications® VVDTMF or equivalent. The VVDTMF shall be activated by capturing the DTMF tones generated by a telephone entry type master station and sending the proper RS232 data to a PC which is running AlphaEntry™ (or other) Alpha Communications® software.

The contractor shall also furnish and install the required VV100D input board, 12VDC power supply, and RS232 cable to connect the VVDTMF to the PC's serial input port (or USB port with the proper adapter).

All wiring to relay shall be low-voltage Class II wiring, installed as per all federal, state, and local electrical and building codes.

VVDTMF DTMF to RS232 Decoder Board

The Alpha Communications® VVDTMF DTMF to RS232 Decoder Boards are used for a variety of applications. The primary use is for capturing the DTMF tones generated by a telephone entry type master station and sending the proper RS232 data to a PC which is running AlphaEntry™ (or other) Alpha Communications® software. The VVDTMF is powered from the (required) VV100D input board.

The VVDTMF boards are designed to easily surface mount right onto the finished wall by using the mounting holes provided for screw mounting, along with the provided plastic stand-offs.

Connections are positive screw terminal and plug-in type.

  • Easily Installs Right on Finished Wall Surface
  • Operates on Safe Low-Voltage Class II Wiring
  • Convenient Screw Terminal and Plug-in Connections
  • Decodes all 16 DTMF tones (0-9, A-D, #, *)
  • RCA Audio input jack accepts line level audio input directly
  • Central office quality DTMF decoder IC
  • LED indicator shows when a tone is detected
  • DB9 female connector for RS232 hookup

3.00"W (77mm) x 1.375"H (35mm) x .75"D (20mm).
Connections: Screw Terminal and Plug-in Connectors
Power Required: 12VDC, provided by the model VV100D Input Board
Alpha Communications
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Due to continuous product improvement, all colors, sizes, materials, finishes and specifications are subject to change without notice.