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From: jeh@dcs.simpact.com
Newsgroups: sci.electronics
Subject: Re: Making an explosion
Message-ID: <1991Apr5.002816.2256@dcs.simpact.com>
Date: 5 Apr 91 08:28:16 GMT
References: <413@crystal1.UUCP>
Distribution: usa
Organization: Simpact Associates, San Diego CA
Lines: 22

In article <413@crystal1.UUCP>, jw@crystal1.UUCP (John S. Wainscott) writes:
> I'm trying to build an explosion sound effects circuit as part of a larger
> circuit but I can't seem to get away from using lots of parts.  The circuit 
> is powered by 3V to 4.5V and the explosion is triggered by a CMOS gate.  I'd 
> like there to be a slowly increasing tone (20-30sec) followed by an explosion
> then silence.

You need LOTS more voltage.  About 120V across a small electrolytic cap, 
say one with a 12V rating, ought to do it.  A capacitor used in this manner
is referred to as a NED -- Noise-Emitting Diode.  

(seriously -- 'round fourth of july, we used to put capacitors out in the
middle of the street (a cul-de-sac), attached to clip leads at the end of a
*long* extension cord.  Plug in the cord and.... the exact result would depend
on the cap and on its safety valve, if any, but most would explode with a quite
satisfying bang.  There was a law in our town banning privately-detonated
firecrackers of all sorts, but it was not illegal to overload electrolytic
capacitors.) 

	--- Jamie Hanrahan (x1116), Simpact Associates, San Diego CA
Internet:  jeh@dcs.simpact.com, or if that fails, jeh@crash.cts.com
Uucp:  ...{crash,scubed,decwrl}!simpact!jeh