MANUAL TEST FUNCTIONS
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For audio analysis, the Mute and Bandpass Filter should be off. Initially, start with the Volume
and Gain settings very low and increase as needed. If the Gain level is set too high, it will
overload the Automatic Gain Control Circuit and the audio board will basically turn off. Also,
care should be taken to avoid feedback with the phone system. It is recommended that
headphones be used with the TALAN to avoid feedback and to be non-alerting while testing.
When the set-up is performed properly, the user should be able to generate good audio
including Oscilloscope views of the digital audio as shown below. The example below shows a
typical dial tone signal on a single pair.
