VoIP conversion

Hello, I hope all is well. I would like to help you with your services and equipment. Equipment that uses FXO or FXS should work fine with your Arris TM804 but I would like to get more details about your setup to make sure I provide you with accurate support. Can you please send a private message when you have a moment? Please include the account phone number, the account number and your full-service address? (with the city, state, & zip code)

  My radio station uses an analog telephone hybrid to connect a POTS line to the mixing console for on-air interviews. Will I be able, using Asterisk, to establish a call on a VoIP phone, put it on hold, and then pick it up on an ATA for routing to the console via the interface device? How about conferencing two calls to the ATA?

so, in reviewing some on-line resources, it looks to me as if the telephone ports on the Arris are FXS, and I need to supply FXO ports on the VoIP server to connect to the Arris ports.

I appreciate your reply and the additional information. I can certainly understand how a solid concrete answer would help in this situation. From what I have researched the ARRIS TM804 should work with FXO or FXS connections. The resources I used to gets more details are: https://www.3cx.com/pbx/fxs-fxo/ and, (https://mediacomcc.custhelp.com/euf/assets/documents/modem%20user%20guides/Arris%20TM804G%20User%20Guide.pdf). I don't see a direct answer looking at the Arris manual but either should work based on what I can see. It may be worth considering what other modems will be compatible with your system and if they are compatible with XFINITY Voice service. Our support is limited once you start using your additional equipment off the modem so I am not sure what features will work once everything is setup and working.