Lots of posts on the forum, and elsewhere, about using VoIP services (like GV) to transmit DATA. In short, dialing isn't usually the issue. The OBi device provides the dial tone, the connected box (from the provider) dials the call when the pendant is activated), and then once the system on the other end (not a person) connects, the box on your end tries to transmit data over the line. This may prove helpful in understanding why it's problematic -
http://hylafax.sourceforge.net/docs/fax-over-voip.pdfIF the system is answered by a person, no data tones sent, then you MAY be able to use a VoIP provider. HOWEVER, you need to contact the system provider you are thinking of using and find out if they support VoIP and answer with a human being that then talks from the pendant to your father without any data being transmitted.
Now - why don't you want to do this? Several reasons:
1) A POTS (plain old telephone service) line is very reliable. VoIP is not. Your GV service can go down because:
a) The internet is down. Your provider is down, someone cut the cable by accident, the cable modem is having issues, the router is having issues (like Dad pulled the plug by mistake several days ago).
b) GV is down. Happens once in a while.
2) Your OBi box locks up and has to be rebooted.
3) Dad unplugs the OBi device by mistake.
In short, I do not recommend that anyone get an OBi device for the elderly, unless it's to SUPPLEMENT a POTS line. My Mom spends $750 a year on phone service. She has an alarm system, and she wants unlimited long distance. She has ZERO technical ability (I'd put NEGATIVE if that made a difference). Can't figure out that the VCR has no tape in it and that's why her show didn't record. Has no idea how to program the Comcast DVR she's paying for... If I got her an OBi device in addition to her POTS line and cut her unlimited long distance, then I would be providing support remotely to her for the OBi, programming it, listening to her complain when it dropped a call, etc.
Do NOT get rid of his POTS line if he has a medical condition, or is elderly and needs RELIABLE PHONE SERVICE.
Since he only has a cell phone, you do realize that if he dials 911 they don't know his address, right? They can triangulate on his location ROUGHLY, but they don't know where he is. So, if he can't speak...
Get him a POTS line if he needs a medical alert device.