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Can I plug my analog phone into the Internet? Please??
November 22, 2011 2:47 PM   Subscribe

I've got high-speed Internets. Also, old-fashioned Fax machines and analog phones. Is there a Voice-over-IP box which _provides a DIALTONE_ and touch-tone-dialing functionality to analog phone devices?

I do understand that the technologies are very very different, but maybe some crafty lad out there has built a box which lets you plug your good old-fashioned Plain-Old-Telephone-System RJ11 phone wires into a box, which then provides dial tone and touch-tone dialing functionality, to then place calls over IP. Has anyone here heard of such an invention? (without buying a complete 5ESS switch system).
posted by shipbreaker to Technology (10 answers total) 3 users marked this as a favorite
 
Phones, yes. Fax/Modems, no.

The compression used to make VOIP feasible wreaks havoc with the compression algorithms used in Fax machines and standard analog modems.
posted by Oktober at 2:52 PM on November 22, 2011


Fax is very possible over VoIP - many modern offices use exclusively VoIP phones and fax machines. Oktober is correct that you can't fax over any old VoIP system, though, like Skype.

What I believe you want is known as a VoIP ATA, but I couldn't recommend one in particular - I'm sure someone will.
posted by speedgraphic at 2:59 PM on November 22, 2011


You are looking for an Analog Telephone (or Terminal) Adapter, commonly referred to as an ATA. Essentially the box Vonage or other VoIP providers send you is exactly one of these. I would definitely call your VoIP provider to see about getting one. Many providers include this in their service. There are also analog adapters for Skype, but I've never used one. VoIP providers through cable companies (Comcast, Rogers, Cox, etc.) have the ATA built into the cable modem, and that phone line connects through to your home phone system.

As for faxing: it can work and work well. The problem is getting it set up properly. The encoding is hell and can be problematic. If you have a newer fax machine you can set it to T.38 transmission mode, which works best over most VoIP services. If your fax machine does not allow for T.38, some of the ATAs can be set to G.711 compression which requires much more bandwidth over VoIP, but works with the majority of fax machines.

As for other modems: Some will work, some will not. The best bet is usually the G.711 mode, but it's shaky at best.
posted by Mister Fabulous at 3:04 PM on November 22, 2011


Linksys makes one, the SPA2102, that supports two analog lines. I use it in a VoIP scenario, but my provider supports fax codecs. I use it for fax machines and a cordless phone for a file room.
posted by johnn at 3:15 PM on November 22, 2011


You might be interested in Ooma. Haven't ever tried it myself but have heard decent things about it.
posted by thewumpusisdead at 3:34 PM on November 22, 2011


Yeah the Ooma, I've got 2 of them. One time setup and unless you need something special, no monthly fees (I pay $10 a month for some Google Voice integration). They're about 200 bucks though you can get them cheaper sometimes at Costco and on Woot. I plug an old school regular phone into mine and they work like champs. There's a strange chime when you pick it up, but it gives you a regular dialtone otherwise.
posted by bitdamaged at 4:33 PM on November 22, 2011


One thing you might find useful in an ATA is a way to connect it back to POTS as well as to the Internet. The Linksys SPA3102 can do this. With one of these properly wired in, your analog phone will ring in response to incoming calls over either VoIP or POTS, and will fall back to using the POTS connection if VoIP goes down or power goes out.

The G711 codecs (G711a/G711u) are the same ones used internally by POTS, and if you pick the correct one (a vs. u) for the country you live in, will introduce no compression artifacts at all as your VoIP call escapes into the POTS network. The latency inherent in VoIP will probably still mess up your fax machine unless both it and your ATA understand T.38 (the SPA3102 does, as will most reasonably non-ancient fax machines).

When you're configuring your ATA you should probably turn off "silence suppression". That feature does save bandwidth, because it stops the ATA sending packets until it detects audio loud enough to be worth bothering with; but it's very disconcerting for the person on the other end of your call because it will make the connection sound like it's cutting in and out (which in fact it is) and it may also screw up non-voice stuff.
posted by flabdablet at 4:52 PM on November 22, 2011


By the way, when I said that the SPA3102 will make your analog phone ring in response to incoming POTS calls, I meant to imply that it will also allow you to pick up those calls and converse normally.
posted by flabdablet at 4:54 PM on November 22, 2011


http://www.legitreviews.com/article/1058/5/

This is great, great helpful stuff. Thank you, all.
posted by shipbreaker at 8:25 PM on November 22, 2011


I use an Obihai OBi110.

This is an ATA device like the ones mentioned above. It has a line port for connecting your land line and a phone port for connecting whatever sort of analog phone you want. I use mine with a red 1978 ITT touch tone phone and a 1941 Western Electric 302 rotary phone (with another device to convert pulse to touch tones). There is also an OBi100 which excludes the line port.

The OBi lets use whatever SIP accounts you may have, but it also lets you use your old phones with a Google Voice account. You can configure two SIP accounts, two Google Voice accounts or a combination of both.

When certain people call my Google Voice number, both my cell phone and my two old phones connected to the OBi ring simultaneously. I can answer on any device I wish. When placing calls with the old analog phones, I pick up the phone, hear a dial tone and dial the desired number.

I keep my land line around for 911 and my home alarm system, but I do not place or receive calls on it. I have the OBi set up to forward all incoming calls on the land line to a second Google Voice account. That GV account is set up to answer all calls with a "We're sorry, the number you have dialed is no longer in service..." intercept message. The GV account plays the message and then presents a busy signal. This takes care of all those irritating telemarketing and political calls!
posted by krynoid at 6:49 AM on November 23, 2011


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