A DIY Voip Handset
Voice Over Internet (VOIP) is for many, a viable addition to a regular landline phone. Shopping around, you can get calls from your computer to landline phones at better rates than regular landline calls.
You can also get an incoming line that people can call without paying a special rate (local geographic number).
The ideal hardware for this is an IP Phone, all the necessary hardware is in the phone itself, you just have to plug it into your router and you can make and receive calls!. These start in price from about £70 (plus vat and delivery). As VOIP becomes more popular, we will be able to pick one of these up in the 'phone shops', but until then, it's mail order.
Lower down the price scale, starting at arround £20, there are USB handsets and Telephones, these plug into a PC that must remain on all the time, and basicly provide you with an extra sound card and keyboard via the USB port. The better (and more expensive) of these, also provide a keyboard function and at the top end of this bracket, telephones, look and act like a regular phone, you can pick up the phone to answer the call, push buttons to start dialing, The actual phone functions are managed by a 'phone applet' that runs on the computer. Because not all handsets and phones emulate the full telephone function (pick up and dial/answer) it is wise to check that the phone you are buying behaves exactly as you expect before you purchase.
At the bottom of the price list (from about £12), are audio handsets, these work just like standard headsets (with boom microphone) exept they are in the form of a standard telephone handset. They plug into the speaker/microphone sockets of the computer and some have an additional pass through allowing regular speakers to be used when the phone is not in use.
You can of couse, dispense with the phone/handset all together, using the built-in mic and speaker of your laptop/computer. This is not ideal (if free) as conversation can be a little strained when having to shout at your computer! A better option is the headset and boom mic combination, the cheaper of these costing only a few pounds and available locally.
The problem with a headset that you wear, is that you need to be in front of your computer wearing the headset to 'hear' that someone is ringing - you're not going to have time to swap speaker/headset cables before they ring off. Also, whilst in conversation, you may want to leave the computer area for some reason - confirm details with others, collect something you left 'over there' - with a normal handset, you simply put it down, with a deadset, you have to disengage yourself from it, reversing the procedure when you return - handsets win every time (in my book).
The first limitation of an audio headset can be easily (and cheaply on a PC) overcome by adding a second sound card to the computer. Using this second sound card as the output for the Telephone Applet, leaving all other sound (including the Ring Tone from the sound applet) results in a phone system that will alert you to an incoming call and not cause problems if you also happen to be playing music (or running a game with noise) through the main speakers.
My Situation
Given the above, I was using an audio headset & extra sound card to provide an internet phone, saving money on outgoing calls and providing a second line. Bearing in mind that one of the main benefits of the system was to save money on calls, I did not want to spend too much money on a full blown IP phone or decent USB telephone (though I'd love to own one!). However, the inconvenience of using the headphone meant that I did not always use the VOIP system - picking up the landline phone to make calls involved less fuss.
After looking at Audio Handsets, I started to wonder, could I use the bits from an old headset and a mobile phone that had been hanging arround for a few years to make an audio headset?
The value of the old phone - an early Ericsson - was probably about £10, and I'd probably never get round to selling it on eBay, I decided to open it up and have a look.
Down to it Making an Audio Handset from an old mobile and a bit of wire from a broken headset
Getting at the innards of the phone proved to be the most difficult part, the screws are non standard (to keep people like me from breaking them!) but a selection of tools from the shed and the kitchen(!) eventually sorted it out.
I took apart the broken headset - I only needed the cable and that was still good - and fed the wire through the phone housing. The phone speaker was connected to the phone circuit board via little spring contacts, I soldered my speaker cable to these, the mic had to be soldered on to directly. Little bits of tape were placed over the contacts to prevent the phone PCB from connecting. I re-assembled the phone with the cable finding its way out between the case and the battery.
 Wow! It worked - the audio wasn't great, but when I ran the Phone Applet audio setup again, it worked better than my headphone - I guess the mobile phone speaker and mic were good quality!
I plan to repeat the experiment with other phones as I come across them - for the purposes of an audio headset, the phone can be broken, we just need the speaker and mic intact.
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Would the same Idea work with a cheap landline phone?
Next, I went out and bought(!) a cheap phone - a 'Telcom Gondola Telephone' or Telcom 200 - £4 from Dixons. This phone is just a handset with integral keypad that sits in its own holder. I didn't expect the results to be too good, but I figured £4 plus a bit of cable from an old headset was still below the mail order price of a handset.
Opening the phone proved to be much easier - all the screws were standard - and this revealed a pcb that runs the phone function, ribbon cable to the numeric pad and wires to the mic and speaker. I cut the keypad, mic and speaker cables to allow removal of the pcb, replaced the phone cable with my audio cable and soldered the mic and speaker leads.
After replacing the case, initial testing showed the microphone picked up much of the speaker output - possibly a result of removing the telephone main pcb - re-running the Telephone Applet audio setup again (to my surprise) sorted that out.
So I now have a VIOP system with a Landline style Handset (the key pad does nothing, its not connected), my additional sound card means that I con still enjoy music through my speaker system and be alerted to an incoming call. When a call comes in, the Phone Applet - I use Xten - pops up and I press enter or use a mouse click to answer it.
When I want to dial, I have to pop up the Phone Applet (Xten), Windows comes to the rescue in the form of 'short cut keys', The Xten installation offers to place a 'short cut' on the desktop, locate this, right click on the short cut and click on the 'Short Cut' field, now press the function key you would like to pop the applet open - I use the numeric '/' key (as I tend to use the main keboard for numbers).
At the end of a call, hanging up the phone normally requires the use of the mouse to click the red hang up button, I found however that 'CTRL and H' will also hang up the phone. Using a shortcut to a little vbscript that raises the Xten window and sends 'CTRL H' to it allows me to map a short cut code to the numeric keypad '-' key. Now I just have to press the number pad '-' key when I want to end the conversation.
Here is the vbscript - replace 'Xten' with whatever window title your phone app has, save it as a text file somewhere on your disk and create a desktop shortcut to it, then you can assign a function key or numbers pad to launch it via the shortcut.:-
Dim Wsh
Set Wsh = Wscript.CreateObject("Wscript.Shell")
Wsh.AppActivate "Xten"
Wsh.SendKeys "^(h)"
Using the Numeric keypad keys to launch the Phone Applet, also allows the use of an additional (laptop style) usb keypad - this can be placed near the handset.
The Free or nearly free Audio handset performs well with standard software, keyboard functions can be re-mapped making it convenient to use, a USB numeric pad brings us even closer to standard phone use, the USB VOIP Phones with integral keypad starting at about £30 are really good value, they include sound and keyboard usb devices (and presumably a small usb hub) inside a handset or desk phone body.
Making usable handsets from a broken mobile and or cheap phone was fun, they work well. If you don't have a suitable headphone to pinch the cable from, try the local 'pound shop', a cable and cheap phone will set you back around a fiver!
Note:
Any of the above modifications will invalidate any warranty and is likely to damage beyond repair any phone that is not already broken!
The prices above are a result of my searches online at the time of writing, wait long enough and you will probably be able to buy 'Audio Handsets' at the local gadget shop - followed shortly by the local pound shop!
UPDATE I have recently been able to combine the above ideas and a Microchip PIC Processor to
Turn a cheap Desk Phone into a VOIP Phone. By using the PIC to scan the keypad, the
phone can be used as normal with no need to use the PC keyboard win making and recieving calls.
UPDATE The Above Desk Phone now has source code available to use it as a Console Phone when plugged into an Asterisk Server's Serial & Sound Ports.
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