Welcome to the second version of the extremely popular service dog GSM activation unit now with one touch dial also sounder to summon help.
1). Now on this page we will look at building a unit that can allow a service dog to activate the one touch dial on a cell phone also at the same time sound a buzzer to summon help.
2). I will follow a similar design as my first version but in this version we will add a Double pole, single throw relay also Diode also on/off switch,PP3 9Volt battery also PP3 battery clip and not to for get our buzzer and case to make it look professional.
3). Now we will look at the parts we need and where to buy them where possible I try to use companies that ship international or you may be able to get the parts in your own country.
4). You will need one buzzer I used the Piezo Siren >100dB two tone output. 6-15Vdc, 150mA. L:47 W:39 H:22mm order it from Bits box Click here they do ship international.
5). Relay Double Pole Changeover 5V 2A @ 28VDC, 500mA @ 125VAC. 36 ohms. Operating Range 3.5V to 6.5V Click here.
One PP3 Battery Clip Click here
One 1N4001 Rectifier Diode 1A 50V Click here.
6).Push to make, push again to Break Switch (Latching) 250VAC 3A. Red Button see photo below also Click here.
7).You will need one or a pack of Pegs for the switch United Kingdom any DIY shop or Ebay if you are in the USA you will need Clothes Pins: Ebay here or Click here.
(Please note this is the type of wooden peg or pins to use in this design don't use plastic)
8). Things you will need one old cell phone with one touch or speed dialing on it Click here or look on ebay in your own country to get an old cell phone for this project.
9). You will also need a cell phone opening kit see photo below or you may get one on ebay cheap from time to time. Please also note don't use a flip phone.
The kit below Contains useful tools designed to assist in the opening and repair of mobile phones especially suited to Nokia and Ericsson and Motorola phones but equally useful when attempting repair on other models click here. If you are in the USA Click here
10). You will all so need solder and a soldering iron I used the Maplin Gas Torch Combination Kit see photo below. You can use any soldering iron just get a small tip this kit from Maplin click here or your local electronic shops or stores. Now if you are in the USA click here.
On the back of the box you can use a clip from a tape measure.
Now for the modified cell phone you can get a phone case off ebay as this often has a clip on the back of the case you can fix both units to your pants.
11). You will all so need one hobby box I used the Small Narrow Box from Maplin electronics Click here If you are out side the united kingdom Click here.
One mono 3.5mm plug or Stereo 3.5mm plug United Kingdom also rest of world this company ship international Click here or you can e-mail me and I will find a link to order them in your own Country. Anthony@anthony-dacko.net
OR 
The above plug is a Stereo plug. The above plug is a Mono plug
3.5mm jack socket - panel mounting. United Kingdom also rest of world this company ship international Click here or you can e-mail me and I will find a link to order them in your own Country. Anthony@anthony-dacko.net
Now if you want an international order Click here Box for the project: Click here.
Now on the next page we will look at building the unit Click here.