Synchronizer (Electronic "Clapper-board")

When talking movies where just starting up,a problem arose.How would one be able to combine the image from the film,with the sound written in a studio sound booth?
That's when the clapper board was invented.It's purpose is very simple.To provide a point by which image and sound can be synced on.
That is achieved by having a wooden board with a stick on top.That way when it's hit,all the editor has to do is find the first frame that the clapperboard is closed,and the first frame on the audio track that the "crack" sound is heard.
Even though tecnology has improved since the 30's the closest thing to an electronic clapper board that exists is a plastic board with LED's on it,that display the timecode.
Synchronizer is completely electronic.

For more info on the clapper-board go to wikipedia's entry at
http://en.wikipedia.org/wiki/Clapper_board

Step 1: Materials and Tools

You will need the following materials and tools:

9 volt battery
9 volt battery clip
piezo buzzer
2 LEDs (I used 2 red 3mm LED's but you can use any colour and size you want)
2 resistors for the LEDs
Momentary switch
Hobby box (mine was a mentos gum box,that was exactly the right size)
Electrician's or gaffer's tape.

Assuming you are using exactly the same materials as I did,it will only only cost you about 5 euros.
This is what I paid.

1.5E for the gums(!),1.8E for the buzzer,the clip,and the switch.
I had the LEDs from some other project.
Finally you can get a battery from anywhere around 1E up until 5E.Mine cost 2.4E.

Blade
Hot Glue Gun
Soldering Iron
Drill (very optional)

Step 2: Cutting,Drilling and Glueing the Box.

You need to cut the box in order to have access inside,and make your connections.
Unfortunately while cutting it,me and my friend managed to break it in two,and we didn't have a spare one.So we had to make some creases for the LEDs to sit on the half-cut bottom.
Ideally you'll want to cut right before you reach the bottom so it stays in one piece,and you can make your holes for the LEDs there.
You can use a drill,to make the holes,or you can try to dig out a hole with the blade.Also make a hole for the switch,and another one for the buzzer's cables,near the bottom.
Once you do,you'll need to place you LED's in their positions and hot glue them.Same with the buzzer.
Finally you need to add the switch.It's your choice whether you want to glue it or not,since it's going to fit just barely,and the solder on the other side,will keep it from falling anyway.

Step 3: Soldering

Now it's time to solder your connections.Solder the resistors to the positive leads of the LEDs and then all the positive leads from the 2 LEDs and the buzzer to one end of the switch.You can use a small piece of cable to make it easier if you want.
Then solder the positive lead of the battery clip to the other end of the switch,and the negative leads of the LEDs and buzzer directly to the negative lead of the battery clip.
To make sure everything's wired up fine,you can place the battery and try it out.

Step 4: Sealing It Up

Just place the other end on top,and seal it up,with either hot glue,or electrician's tape.
I wanted to use black gaffers tape personally,so that it wouldn't look that bad,but I didn't have any left.
You can try to use other color hobby boxes,switches,or LEDs for a personalised Synchronizer.
If you do,leave a comment or even a photo.

Step 5: Things to Add

I wanted to submit this in time for the LED contest,so there are a few things I left out,to have it on time.
These are things I need to add.

*Redo it,without cutting the box in two.
*Add video and audio of synchronizer in action.
*Change Power Supply.9 Volt battery fits just barely in the box,so i wanted to use button cell batteries to reduce the mass.
*Add more photos,and hopefully have them focused.( My internet connection is trying to upload a 3MB picture,for the past 10 minutes!) DONE

I will update this instructable as I add these things.

Thank you for reading my tutorial,and please leave a comment.

UPDATED:
Photos are up.