ODP: +5v trigger for tap tempo

[Roman Sowa]

Maybe something like this:
Ramp generator, not especially linear, say, RC. After powerup or some
sort of reset it is shorted to GND. When you first hit the tap button,
the short is released, and voltage rises. When you hit the button for the
second time, it triggers S&H tracking the ramp. S&H output feeds
comparator input, while its second input is driven by this RC generated
ramp. Shortly after triggering S&H comparator's output goes high, and
resets RC ramp generator. Voltage drops to 0, comparator goes low and
ramp starts new cycle. When voltege reaches the level set in S&H
comparators resets ramp again. Voila!
To stop this generator, you might reset flip-flop, which kept RC shorted
and then got released. Well, I have idea in mind, maybe schematic
would be more explanatory.
I say S&H, comparator, 2 D-flops (4013), and maybe little more logic.

With this circuint you can later set faster tempo just by hitting the button
sooner than expected beat would come, but to make it go slower it needs
to be reset. More versatile devise could be done in software (PIC?)

Hope this helps. 

Roman

> -----Oryginalna wiadomość-----
> Od:	mark scetta [SMTP:n0nspaz at loa.com]
> Wysłano:	15 lipca 1999 21:01
> Do:	synth DIY; analogue list
> Temat:	+5v trigger for tap tempo
> 
> hi lists,
> 
> i am a novice to electronics (i'm building a MOTM modular...) and an avid
> analog synth freak. i need help with the electrical specifics of building
> a
> tap tempo trigger box that i will use to set the arpeggiator rate on my
> Jupiter 6. here are the details:
> 
> the JP6 has a trigger in that will set the arpegg clock rate. it is
> designed
> to get its pulse from a TB-303, putting out +5v. i would like to DIY
> something that puts out this pulse *and* has a tap-tempo interface so that
> when i tap it twice, it assumes that tempo. also it must have some kind of
> bypass or on/off switch (for times when i'm not using the arpeggiator). i
> think what i'm trying to build here
> is a metronome of sorts, but i'm not versed enough in electronics to be
> able
> to design it, especially the tap tempo part.
> 
> any help appreciated,
> mark
>