The Alarm is a Nexxtech personal alarm
at the source. Part No 4900428 at the Source. Sorry... I can't find the equivalent on RadioShack's website.
Part 1 : The parts we need
Here's the handlebar 5 LED light we'll use. I already have 2 of them. One will be used as a light and the other will be the horn. That way it looks nice on the bike and it'll be nice and compact... and loud.
Lets open it up and take a look inside. We have the cap, the battery holder, the outter casing and the mount.
Now lets really tear it apart. These are all the bits and pieces from the front to the rear.
Now we'll discard the pieces we don't need. I just put them in my parts bin for future projects. Those 5 ultra bright LEDs may come in handy in the future. The only piece that we'll need from the LED light are these:
The next part which will actually be our Horn is this gadget:
It uses an A23 12V battery and has a 140db ear piercing siren. You simply pull the keychain ring out, much like a handgrenade pin, and the blue part will scream its head off until the pin is put back in.
Lets take a look of its internal parts.
Next I discard the parts I don't need to my parts bin. What remains is what we really need.
So here is the final parts we'll need for this project.
The pushbutton switch was a spare I had laying around in my parts bin. The goal is to remove the pin holder on the alarm and replace it with the pushbutton. The wire will be sticking out of the back of the casing. All those alarm parts in the middle will be crammed into the light's battery holder (the black thing at the top middle). The lens on the top left will have a hole drilled right through the middle to let the sound go out forwards.
The next step will be drilling, cutting, soldering and so on. I'll probably introduce a few odd bits here and there to complete the project though. We'll see as it goes along.