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Telephone Supervisory Adapter
For telephones that do not have side-tone on the earpiece



The TSA-2A1 is used to provide a method of connecting supervisory monitoring equipment to the handset (or headset) circuit of a telephone that does not have side-tone (no mouthpiece audio is present on the earpiece of the phone - also called talk-back). It can be used on most telephone styles that have a standard modular handset or headset jack (4P4C). If the phone you wish to monitor has side-tone, as with 99.9% of business phones, you should use the simpler and less expensive TSA-3LM adapter.



The TSA-2A1 is supplied with cables and connectors which have been wired for use with Total Recall and TeleCorder recorders from Omnicron. The cable between the TSA-2A1 and your recorder may be extended as needed. Only the center two wires in the output cable (red & green) are used to feed audio to your recorder.


1. Unplug the handset cord from your telephone set and plug it into one of the two jacks on the TSA-2A1 adapter labeled “Handset/Headset — IN/OUT”.


2. Using the short cable which was supplied with the TSA-2A1, plug one end of the cable into the handset jack on your phone and the other end of the cable into the remaining “Handset/Headset — IN/OUT” jack on the TSA-2A1. Your telephone should now function normally as you have simply connected a short extension into the handset cord. Normally the center two wires on the handset jack are the earpiece circuit and the outer two wires are the microphone. If your telephone does not use standard connections, the TSA-2A1 may have to be re-wired so that the recorder is connected to the correct wires.


3. Plug the supplied AC adapter into the “Power (12vDC)” jack and AC power.


4. The “Audio Out” can now be connected to your supervisory equipment (voice logging recorder, monitor amplifier, etc.). The TSA-2A1 comes with a twenty-five foot cable which can be used between it and the input on your recorder. Do not connect the “Audio Out” to anything other than the audio input of your monitoring equipment. Never connect it to a phone line.


5. There are two small screwdriver adjustable controls on the TSA-2A1. One adjusts the level of microphone audio that is on the its output (up to 30db gain), and the other adjusts the earpiece audio (up to 10db gain). Adjust clockwise to decrease, counter-clockwise to increase the output level as needed. Secure the cables.



The TSA-2A1 is warranted to be free from defects in materials or workmanship for one year from the date of purchase. Damage to products resulting from physical abuse or electrical misuse voids this warranty. Out of warranty units will be repaired for a nominal handling charge plus the cost of parts and transportation. If the unit requires service, disconnect and return to the factory or place of purchase for repair.


Federal law 90-351 title 18, section 2511, sub section 2D, requires that at least one participant in a recorded conversation be informed of the recording. Check your state and local regulations for further guidelines.


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


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