[sdiy] Rectifier for logic level pulse?

[mark verbos]

look at the Digisound VCDO. It uses something like this to double the  
oscillator frequency going into the counter. It involves  a cap and  
resistor going into an inverting gate and a cap and resistor going  
around it.

Mark




On Sep 28, 2009, at 7:22 PM, Tim Parkhurst wrote:

> Hello Y'all,
>
> I'm looking for a circuit that SHOULD have been a simple thing, but it
> it escaping me. I have a circuit that take a CMOS level pulse,
> differentiates it, and uses a diode to lop off the negative pulse that
> occurs when the CMOS input goes low. Simple: one cap, one R, one D.
> What I'd like to do is add another diode (or three) and "rectify" the
> negative pulse. Essentially, what I need is a circuit that produces a
> short positive-going pulse when the input goes low to high (that's the
> easy part) AND another positive-going pulse when the input goes from
> high back to low (the not so easy part). This should be simple, and I
> can swear I've seen this done, but I just can't find it for the life
> of me. Should be just like a full-wave rectifier, right? I'm sure it
> will be a "D'OH!" moment when the solution is pointed out, but I can
> live with that.
>
>
> Tim ("Rectifier? I hardly even know her!") Servo
> -- 
> "Sire, the church of God is an anvil that has worn out many hammers."
> - H.L. Hastings
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy