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'Cause and Effect' can anyone help?

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i have no idea about electronics so if anyone can help i'll be very grateful

Im looking to make a prototype of a product with similar actions to the following if you could offer advice.......

Imagine a plastic toy head(hollow) mounted on a vertical springy cylinder leading to supportive base. Now what if every time someone slapped it on the head it wobbled emitting an audio response like 'Hey man!'.

I figure i would need a small speaker inside the head with its wire running through the cylinder to its supportive base where i imagine i would need a device to sense the 'hit' which in turn alerts a soundboard which releases the 'hey man!'.

what i want help with is the specific terminology regarding the possible components to allow this set up. i mean what is the procedure used for getting audio onto a 'sound board' (is that the right terminology?) what may be used to sense the 'hit', should there be a motion detector device in the head to register the hit? thus feeding the signal to the soundboard? does a programme have to be written then stored on the soundboard to account for random audio responses? it even the right component set up...something else?....its just so i have general specs before I invest....

if anyone can offer specifics to this set up i'd be very grateful or more info>

Thanks :?
Hi 1shade,

The sensor for a physical disturbance is fairly easy,
a bit like a car alarm.

you would need a little battery, and a little speaker
probably in the base, along with a chip to store the
short audio in digital form.

If its just one short audio clip, then i think you
could find a ready-made chip to accept a digital stream.

You could probably put the clip you want onto your PC
as a 'sound recorder' file - choose the mono, and
minimum quality, then see about transferring it to
a chip.

I have never done this,
but i feel sure it can be done.

See this article about converting a bit stream into
audio by Roman Black.

He has done some excellent work on this.
He has also put forward what he calls 'bit and a half'
which is a novel idea of re-using the same bitstream
one bit delayed, and added into the out signal in the
same way as the original, he says this gives a better
overall effect.

He explains it better, and with pictures.

Certainly worth a look.

Regards, John :)
Ive just been re-reading that article,
and Roman says he can get 17 seconds from a 32 k-byte eeprom.

A quarter of a minute of audio from 32kb is an achievement indeed.

If that is what he means, and i think it is.
You could fit a LIMERICK into that length of time !

Regards, John :)

maybe u could use a mercury switch or reed switch as a motion sensor. very cheap and easy.
A mercury, vibration switch or peizo transducer to detect the 'hit' - or even maybe the speaker it's self? If you don't want to be messing in what sounds like advanced pic programming (although I will definately read that artical!) and not to mention I can't imagine the sound quality to be great out of a pic you would shorly need a lot of filtering etc.. There is a company called greenweld (type into google) that sell the 'birthday card chips that you can record your own short message onto - it is obviously compact and everything required for the audio is there you would just have to switch it with a transistor / fet or somthing. They are also fairly cheap.
Your anwser lies in the arcade

Have you ever seen kids in an arcade pounding those buttons thousands
of times a second and they keep on ticking. Arcade electronic buttons
are designed for high impact so here is a suggestion take your projects
"head" and design it so that when it is compressed a spring collapses
then causing a rod like extension in the middle bottom of the head to
hit an arcade like switch (like a play switch -normally open ...until pressed)
then this actives the audio that you previously recorded on a chip via a computer program. back to the head design once the pressure of the spring is returned to the resting position the switch and the rod on the head is not physically touching the button

just a thought you know

agent99 - simple but elegent - I use to repair bandits and I can tell you the switchs underneath the buttons are just large micro-switches - Oh and they probably don't last quite as long as you think they do but they do last a long time! Depends how rough the git is who's playing and whether they are on a good day or not!
why cant a simple push switch used for the head "hit"? maybe some sort of force transfer might be needed if the switch is placed say around the neck of the ty, but that's purely limited by mechanical design only.

Juz my 2 cents :)

Check out the ISD Chipcorder.

**broken link removed**

These very easy to use devices contain on a single chip, a microphone preamp, 20 to 120 seconds of voice recording (depending on the chip) and speaker drivers. It is also fully addressable, so you can record numerous sounds or messages and play them randomly. I found ISD's documentation to be very thorough and helpful.

Look for the ISD2560 at This is the 120 second version. It sells for 8 bucks. The 20 second version sells for about 5 bucks.

I am planning on using the 2560 to make a toy for my daughter. I am going to take a phone and rework it so that when she pushes a number pad she hears me or my wife saying something to her.

BTW my only issue with ISD is they claim you can hear the chip's output on a 16 ohm speaker from across the room. For me you can barely hear it at arm's length. But then again I am a total beginner and know very little about audio electronics. I am hoping it will improve when I move it from the breadboard to a pcb.
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