Saturday, September 19, 2009

Use Google Talk, Skype, or a SIP based VoIP client a lot? Take it from me, being tethered to the PC gets old … fast. To solve this issue, many cordless VoIP phones have become commercially available, but as we tend to do around here, let’s make our own instead!

Ok, ok, I hear what you’re saying and yes, I am aware that this particular project is somewhat old… like, four years old to be precise… but I’ve been compelled to post about it as the landscape of VoIP, SIP and other open (free) telecommunications options on the Internet has changed dramatically since 2005… While I made my first DIY VoIP phone way back when, it hasn’t received much use since the conclusion of the now-infamous “Free Skype-out promotion of 2006”…until recently that is…

So here's the plan...this post will have two parts: In the first, we’ll go over how to make your own DIY VoIP Phone (to bring everyone up to speed) and in the second, we’ll have some fun with the phone and go through a few ways you can start making some free calls! Huzzah!

Part One: Making a DIY VoIP phone

Required Parts:

1. A cordless phone… The original hack from Grynx used a fancy schmancy Siemens phone, but I’ve had success with both Radio Shack/The Source and VTech models. Live dangerously and just buy the cheapest one you can find.

2. One (approximately 6 ft.) 3.5mm male/male stereo audio cable like this

3. A soldering Iron and basic soldering knowledge… You can brush up on your skills with this great guide here.

There have been many posts on making both VoIP phones and VoIP adapters, but one of the original and best guides was posted by Chris J. at View it here. Alternately, there are also plans here if you’d rather make an adapter so that no modification to your phone is necessary... It should be mentioned that once you modify your phone with the audio cables, you shouldn't try to plug it into/use it with a regular phone line anymore...

Chris J.’s guide is very straightforward, so I don’t need to go over it all again, but I’ll explain it briefly for the curious-without-the-intention-of-making-one...

With the circuit board exposed and the handset on, a small screwdriver is used to probe the various parts of the cordless phone's circuit board in search of where the tapping of the screwdriver can be heard in the handset. Using a halved audio cable, a signal can be sent from an mp3 player into this spot to verify its location. Alternately, to find the “mic”, simply blow or talk into the handset and test the board with a pair of headphones, listening again for the location where your breath/voice can be heard. The two halves of the audio cable are then soldered in place at both locations. The end result will probably look (better than) something like this…

Some candid shots of the Vtech 9118... Just about any cordless phone will do...

Part Two: Having fun with your DIY VoIP phone

While much of this depends on what country you’re in, but hopefully there’s enough info here for just about anyone to piece together a solution that works… I tried a whole bunch of different services (close to 12!) to see if free calling could really be possible here’s an overview of what I found, and what kind of service you can get for free...

Skype is actually a great place to start messing around with your VoIP phone, even though their free calling promotion is long over… By using a service called 1-800-free-411 along with Skype, you can make free 5 minute VoIP calls (even internationally) to regular phones… not bad!
Just start-up Skype and then dial *wait for it* 1-800-Free-411, listen to the ads, and then just dial your number… pretty cool… but what about that 5 minute restriction? Let’s push our luck!

The first real providers I investigated were fairly run-of-the-mill SIP providers such as, VoipCheap, and VoIPStunt. Having tried all three, I’d only recommend them to those who require only incoming calls. One way to do this is to use one of these services' softphones and link it with either your own Enum or with a service such as Voiptalk. I used Voiptalk to register a local number in the United Kingdom, and then linked it to my VoIPCheap softphone. This way, my friend in the UK can now make a call to a local number, and I will receive it on the softphone/diy VoIP phone. Many other providers of free access numbers also exist, so you could conceivably set up multiple local numbers to accommodate multiple international friends with unique numbers that all connect back to you, wherever you may be.

It’s worth noting that registering for any generic SIP provider (such as the three I mentioned) will provide you with a unique SIP number. Like the Enum, SIP numbers can also be called using regular telephones or POTS (Plain Old Telephone Service). A very cool site called SIPBroker maintains a large list of international access numbers that can be used to call both Enum and SIP numbers. Simply find and dial a local number on their list, and then enter your desired [sip-code][number] or ENUM number at the prompt. Easy!

So there are a few solutions, but admittedly, each has its own drawback; but there are a couple services stand out among all the rest… For Canadians, the best free VoIP solution out there can be found at Not only will the site provide you with a local Canadian number but it also offers free incoming and outgoing calls between these cities:

Ajax-Pickering, Ancaster, Athens, Aurora, Ayr, Baden, Bolton, Bowmanville, Brampton, Breslau, Brockville, Brooklin, Burlington, Caledon East, Calgary, Campbellville, Cardinal, Carleton Place, Clarkson, Cooksville, Delta, Drayton, Dundas, Edmonton, Elmira, Exeter, Fort Erie, Freelton, Galt, Georgetown, Halifax, Hamilton, Hespeler, Hull, Kanata, King City, Kitchener, Linwood, London, Maitland, Mallorytown, Malton, Maple, Markham, Milton, Montreal, Mount Hope, New Dundee, New Hamburg, Newcastle, Newmarket, Niagara Falls, Niagara-On-The-Lake Nobleton, North Augusta, Oakville, Oshawa Ottawa, Pelham, Plattsville, Port Credit, Port Perry, Prescott, Preston, Quebec City, Richmond Hill, Roxboro, South Pickering, Spencerville, St. Catharines, St. Clements, St. Jacobs, Stittsville, Stouffville Streetsville, Thornhill, Thorold, Toronto, Unionville, Uxbridge, Vancouver, Waterdown, Waterloo Welland, Wellesley, Whitby, Windsor, Winnipeg, Woodbridge.


Incidentally, everyone in the world can make calls to the United States with a DIY VoIP phone and the website. Simply enter your desired number, wait nineteen seconds and make up to a fifteen minute call. Good deal, but unfortunately it lacks a dialpad, so it's useless as a hopline.

For Americans, your best bet is The service will similarly let you make local and international calls through a local access number, but unlike, you’ll need to use a regular phone.

The potential for VoIP and SIP calling is immense. These technologies clearly have huge implications for the power structure of contemporary telecommunications... This is particularly apparent in the case between Apple and Google at the moment, with the former viewing the Google Voice app as a threat to iPhone's very existence. But I digress...

Try it out! Set a number up as a business line, or have some fun calling a distant friend/loved one/enemy/complaint department/or *ahem*... even other uses!

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posted by Marcus at 11:52 PM |


At September 23, 2009 at 8:53 PM, Blogger Donovan said........
So, with the callamerica website, how long do you have to wait for another 15 min (after you run out)?

At June 23, 2010 at 9:11 AM, Blogger Unknown said........
Unlike the cable network connection, the Free VoIP services can be availed without any extra wires. A broadband internet connection is all that is required in many instances. And the best part is often the optimized "voice quality" that can be attributed to the broad bandwidth of the network connections.

At February 14, 2017 at 11:43 AM, Blogger codeasy said........
In addition, one should remember that the voip supplier needs somewhere to get this voip traffic. For example wholesale voip portal, so there will be always some margin over the payment to supplier.


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