Omnicron Electronics - Professional Voice Logging Recorders and Accessories - since 1975 
 Professional Voice Logging Recorders  and  Accessories


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Total Recall
4 to 72 channels
Total Recall MAX
10 to 92+ channels
2 or 4 channels
2 or 4 channels/PC

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Omnicron Electronics - Professional Voice Logging Recorders and Accessories - since 1975

Telephone Supervisory Adapter with
proximity sensing audio muting switch

        The majority of microphones in telephone handsets are not active (hot) when 
the phone is on-hook. If you use our standard TSA-3LM, room audio between calls will not be recorded.  However, if your recorder picks up sounds between phone calls, the TSA-MRS will mute the audio when your telephone handset is on-hook. The TSA-MRS prevents sound activated recorders from triggering between calls.



          The Omnicron TSA-MRS is used to provide a simple and inexpensive method of connecting audio recorders to the handset circuit of a telephone. It is usable on most telephone styles that have a standard modular handset jack. It has a small proximity sensing magnetic reed switch that is used to mute handset audio when the supplied magnet (mounted on the handset) is within 1/2" of the sensing switch.

          When used with a voice activated logging recorder, such as Total Recall from Omnicron, the recorder will record phone conversations when the handset is off-hook (records handset audio), and stop recording when the handset is hung up. To prevent extraneous audio from triggering the recorderís sound activation circuitry when the phone is not in use, a proximity sensing switch mutes the audio output to the recorder when the handset is returned to its cradle (hung up).



1. Unplug the handset cord from your telephone set and plug it into one of the two jacks on the TSA-MRS adapter.

2. Using the short cable which was supplied with the TSA-MRS, plug one end of the cable into the handset jack on your phone and the other end of this cable into the remaining jack on the TSA-MRS adapter. Your telephone should now function normally as you have simply connected a short extension into the handset cord.

3. The sensing switch is attached to the TSA-MRS adapter by a 10" white wire. Use the supplied small double stick foam pad to mount the sensing switch to your telephone base so that it will be within 1/2" of a spot on your handset that is suitable for mounting the small magnet (same size as sensing switch, but without wires) on your handset. Use the 2nd small double stick pad to mount the magnet on the phone handset so that it will be within 1/2" of the switch on the phone when the handset is in its cradle (on hook).

4. Locate a convenient spot on your phone to mount the TSA-MRS. Insure that there is enough slack in the cables so that they can be un-plugged, and that it will not interfere with the operation of the phone. Attach it to your phone and secure the cables using the large double stick foam pad and cable ties that are included.

5. The TSA-MRS adapter can now be connected to your supervisory equipment (voice logging recorder, monitor amplifier, etc.). It has a twenty-five foot output cable with handset audio on the 2 center wires when the handset is off hook. It can be used to feed audio to the input of your recorder so that both sides of all conversations on the handset can be monitored. If your telephone or recorder does not use standard RJ11 connections, the plug may have to be re-wired.

          If your monitoring equipment interferes with the operation of your phone in any way, or if your monitoring equipment is not designed to be connected to your telephone in this manner, a different means of interconnection may be required.

bulletContact your Omnicron representative for assistance in the selection of the products that are best suited to your application.



                             Prevent costly mistakes - record all important phone and two-way radio conversations. Compact, economical recorders that document every word of your important conversations.
                                   OMNICRON ELECTRONICS
                        581 Liberty Highway,  Putnam, CT  06260

(860) 928-0377

(860) 928-6477

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