ISDN/T1 Telephone Recording Guide

Telephone Recording Options

Digital lines carry a proprietary signal which means calls cannot be recorded from the line itself unless specialized equipment is used. The most simple and cost effective method of recording digital lines is using a handset adapter. A handset adapter converts a digital signal to an analogue signal when it reaches a telephone handset (unless the handset is also digital). See the diagram below for more details.

A second option for large scale operations is a digital telephony card that is specially configured for your line depending on the protocol used. Is should be noted that this is a very expensive operation (starting at $2000.00 USD for a base board before configuration) and requires a board to be built based on your phone network configuration. However, if you are interested in receiving a quote for a board please contact our Corporate Sales team for more information.

Single Line ISDN/T1 Setup with Handset Record Adapter

VRS Recording System - Click for more information on this product
Call Recording Adapter - Click for more information or to purchase this product
TRx Phone Recording System - Click for more information on this product


You will need the following hardware for this guide to be useful:
  • An ISDN or T1 line
  • An ISDN or T1 compatable phone.
  • A call recording adapter.
  • A computer with a sound card
  • The VRS or TRx Recording Systems. You can download this software free - VRS, TRx.
Setting up a single line ISDN/T1 system is easy. Just follow the instructions below, and, if in doubt, refer to the diagram above.
  1. Disconnect the handset from the ISDN compatable phone.
  2. Plug the ISDN or T1 cable into the base of the phone.
  3. Connect the base of the phone to the Call Recording Adapter
  4. Connect the Call Recording Adapter to the audio jack in the back of the computer. Also connect the Call Recording Adapter to the phone handset.
  5. Download and install either the VRS Recording System or the TRx Phone Recording System on your computer.
  6. You are ready to go!