I decided to go for a hardware solution so I did not have to use some software on a PC to make phone calls. Hence I bought an ATA (Analog Telephone Adapter) to be able to use my normal telephone. The ATA I bought is a Sipura 3000, it has got 3 ports, 1 LAN, 1 FXS and 1 FXO. As the device has an FXO port it can be connected to the PSTN line and configured to route calls either over Internet or PSTN. So I only need one phone to make calls over Internet or via the normal telephone line, depending on the number I dial the ATA will route my call properly.
There are many companies out there providing SIP services. At the moment I have an account with voipdiscount.com. There are a bunch of SIP providers with similar names: sipdiscount.com, voipbuster.com, voipstunt.com that are owned by the same company, Betamax/Finarea. All of these sites are basically the same thing. One thing though is that they have different offers and when I signed up voipdiscount.com was the most beneficial.
Voipdiscount.com offers "free" calls to more than 40 countries around the world. It is not 100% free but the deal is good enough!
Here are the details:
* Max 300 minutes of free calls per week.
* Free calls is only possible for 120 days after the account has been recharged.
* Minimum amount to recharge is €10 + VAT.
* Normal call rate is €0.01 and will be charged when out of free calls.
I also have an Asterisk Linux machine which I use in combination with the ATA. Below is some pictures of the box next to the Sipura ATA.
The case is a Morex Cubid 3688 with a mini-itx VIA EPIA ME6000 motherboard. It has an integrated fanless CPU, 600Mhz Eden architecture. I use 512MB RAM and 40GB 2.5" HD. The case has only space for one laptop HD as you can see from the pictures above.
This architecture is low power consuming and hence produces very little heat. At normal operation it consumes less than 30W! The only fan is the one that came with the case. I was not very impressed by this fan as it produced way to much noise. To have this box on 24/7 I needed something very silent. So I decided to decrease the rotation speed by lowering the voltage to the fan. I did this by installing 2 diods, each introducing a voltage drop of 0.7 volt.
I am running the Asterisk@Home Linux distribution and it is working well. The Asterisk@Home project has been replaced by Trixbox but I have had no time for an upgrade. Early versions of Trixbox also had some issues to install properly on the i586 architecture so I also did not want to bother with a custom install.