Last month, we switched to VOIP. Our VOIP provider is voip.ms, and we use an Analog Telephony Adapter (ATA) to connect our existing phones to our VOIP provider.
As expected, our phone bill is slightly less than $10/month. It includes every calling feature that I know of (call display, call waiting, voice mail, call forwarding, caller ID filtering, …)
One issue we’ve had is with the ATA: when talking to high-pitched people, we heard touch tone beeps, and it could be very disruptive. Apparently this is called DTMF talk-off. It is not the VOIP provider’s fault, it is our equipment that’s causing the problem. Here are the proposed fixes I found on the web and the results:
- use the g711 codec: did that, problem persists
- upgrade the firmware on the ATA: done, and no effect
- Set the DTMF transmission method to INBAND: did that, problem persists
- Set “DTMF Process INFO” and “DTMF Process AVT” to OFF: problem solved!!!!! … hopefully (still too early to tell)
We still use our answering machine (we can be both high-tech and retro), but it’s possible that the last 2 items would interfere with IVR services such as voicemail if we used them.
While it’s still too early to tell, the service so far has been more reliable than the service we used to get from a certain telephone company – the telephone lines in our neighborhood are in a state of complete disrepair, I’m fairly certain that everybody on our street switched to cable or cell phones – I don’t see their repair truck anymore, but their decrepit infrastructure is still in shambles.
In the event of a power outage, we would have to rely on our cell phones to make calls. I looked into getting an uninterruptible power supply, but it would get us less than 1 hour of service – the wave generator, which converts DC to AC, seems to be extremely wasteful. My best bet would be to get one 5V battery (for the router and ATA) and one 12V battery (for the cable modem) and connect the batteries directly to the devices, thus skipping the wasteful conversion: DC to AC and then AC to DC again.
In fact here’s a product idea: an uninterruptible power supply that provides DC power: no AC output, it should instead have several output cables with interchangeable tips to connect to various equipment. It could probably be quite small and use lithium or NiMH batteries; I don’t think it would require a huge lead-acid battery. I would buy two: one that’s 5V, another that’s 12V, unless you can combine that into one unit.
EDIT: Nope, we still get touch tone beeps. The solution would be to get a better ATA, or a get pure SIP phone, no analog conversion. Based on the information I found, setting “DTMF transmission method” to INBAND should completely stop the ATA from trying to interpret any sounds as DTMF tones; either this information is incorrect or the ATA does not support INBAND (other than displaying it in the web interface.) As a last resort, I unplugged the ATA and plugged in back in, perhaps then the setting will finally be in effect. I also set all the fax-related stuff to disabled, in case those aren’t DTMF beeps but some sort of stupid FAX-related functionality. But we all know it won’t work.