[sdiy] Trigger to Gate Converter?

[Ken Stone]

What you are looking for is called a monostable multivibrator. Once can be
knocked up using a common 555 timer chip (look for circuits designed to use
the 555 on the web or wherever, but when actually constructing it, use a
7555 timer instead).

Ken

>I've got a tiny circuit based around a NPN transistor in my Casio SK-1.
When a 
>+5v trigger is feed into an 1/8" jack it is just like pressing the 'One Key 
>Play' button manually.  In this manner I can step through the sequencer of the 
>SK-1 with a trigger from a drum machine.
>
>The problem is the trigger from my drum machine is a very short pulse and it 
>has the effect of quickly tapping on the one key play button.  The sample in 
>memory does not play for very long.  This is ok for quick percussive sounds, 
>but not suitable for anything else.  Is there any sort of simple circuit out 
>there that would act like a trigger to gate converter?  I'd ideally like to 
>find something that has a control for the length of the gate time, so I could 
>essentially stretch the length of the pulse to match how long I'd want the 
>sample to play.  Thanks for any info,
>-Jim
>
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_______________________________________________________________________
Ken Stone   sasami at hotkey.net.au or sasami at cgs.synth.net
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