Instructables
Convert a totally underwhelming foam skull into a Halloween speaker system.

-=Backstory=-

I was at Abott's party store in Littleton, NH a couple days ago and saw a foam skull. Upon first glance it looked like your basic Halloween prop, until I saw the LEDs in its eyes. I immediately knew this would be the prop of a lifetime... with the sort of technology it was hiding in its cranium, the skull might be able to:

a) Scare the daylights outa the neighborhood kids
b) Dispense fortunes when it detected questions directed at it
c) Do the dishes, walk the dog and fetch me a beer
d) All of the above

With visions of sugarplums dancing in my head, I reached down with hands trembling in anticipation and flicked the "ON" switch.

Its eyes lit up.

they didn't even blink.

I was utterly devestated.

It was then and there that I decided to remedy this great injustice. I purchased the skull and began brainstorming.

Ten Redbulls later I hit upon an idea...
What if the skull could talk...
what if his eyes lit up while he talked...
Brilliant!

so I set to work...

Step 1: Gathering Materials & Disassembling

I used the following materials for my skull:

note: double all amounts for stereo setup

1x foam skull with led eyes ($12.99)
1x 8ohm speaker (scavenged)
1x TIP31 npn transistor ($1.59 at radioshack, :( )
1x 1/8th inch mono phone jack (6 for $3.99 at radioshack :( )
1x stereo to mono 1/8th inch adapter ($2.99)
lots of thin wire (scavenged from a previously mutilated usb cable)
soldering skills

The first step is to remove the four screws holding the base on and snip the wires to the leds, leaving a stripable amount attached to both the LEDS and the battery box

Step 2: Build Circuit

build the circuit shown below from your components...

Their are two essential, traceable circuits in the overall diagram they should go as follows

Light Circuit:
positive terminal of battery box unit goes to LEDs (in series)
negative terminals of LEDs go to transistor's Collector pin
transistor's Emitter pin goes to battery box unit's negative terminal

Controller Circuit:
Positive terminal of phono jack goes to speaker and transistor's Base
Negative terminal of phono jack goes to speaker and transistor's Emitter
 
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riverreaper4 years ago
could you post a movie ? it say flashing but we cant tell that from pic ,ive set of lights that will flash if box is bumped slighly , a phones vibration would set them off some red plastic in the eyes would be glowing now ive to find scules 3 months befor the day of lol
BigMatt.ZA7 years ago
im confused, is this so you can talk throught the skulls and scare the sh*t out of people....cos thats cool and all, but as pc speakers it would rock evn more.
scavenge it boy.
Neech8 years ago
Sweet idea, I want one. What did you use for your power supply? 3V - 2AA? Why does your ciruit have the diodes in parellel?
gschoppe (author)  Neech7 years ago
they're in parallel because thats the way the skull was already made... if you made your own, you'd want them in series
Junkernaut8 years ago
Sweet Halloween Idea. that looks like you could make a iskull ipod dock
Neech8 years ago
Sweet idea, I want one. What did you use for your power supply? 3V - 2AA? Why does your ciruit have the diodes in parellel?
Robotrix8 years ago
I applaud your commitment to giving halloween props the respect and ingenuity they deserve
gschoppe (author) 8 years ago
Just to give credit where due, I chose my transistor based partly on its use in the blinking led project at:
http://www.instructables.com/id/E1K7SJ2ZG6ERIE36TP/?ALLSTEPS