Hello and thank you for posting to our forum.
The TA 900(e) series will send caller-id in the form of FSK toward the end user. The details are explained in this document:
Are you doing an application where you need DTMF sent toward the customer prem? If you can provide more details of your application including when you are looking to send DTMF or FSK, I can better answer your question.
As for the analog signal level, there are gain adjustments that can be made in the analog FXS user. The rx-gain default level is -3dB and can be adjusted in 0.1dB increments between -12dB and +6dB. If the level is lowered (ie. -3dB to -5dB) the signal sent out the FXS port to the end user will be lower. The tx-gain default level is -6dB and can also be adjusted in 0.1dB increments between -12dB and +6dB. If the level is lowered (ie. -6dB to -9dB) then the signal received in on the FXS port being transmitted to the far end will be lower.
Let us know if you have any questions.
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