This is very neat. An uglier way to do it is with an off the shelf pulse to tone box and a router with VoIP support, like an N300. Do you think it could use W

This is very neat. An uglier way to do it is with an off the shelf pulse to tone box and a router with VoIP support, like an N300. Do you think it could use WiFi calling? I suspect that can't be done is it requires one of a limited set of carrier approved phones in each area.