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Re: [Doepfer_a100] Soft Sync on A111

2005-02-07 by Josue Arias

Yes, I`ll try a short inverted pulse but why wasting an inverter? the
resistor and diode ARE there for driving the sync with a saw wave!

The good about the modulars is that you can end doing the same
operation using several approaches! :)

Best Regards,

Josue.







> > You can check the Manual.
> The schematic of the A111 shows the blank input for the Pin 9 of the
> CEM3340 (only additions are a pull down resistor and a zener diode for
> eleminating positive signals (schemo see page 1 of the service manual
> and explanation page 7). So beside of the zenerdiode and the pulldown,
> the Softsync input is designed as suggested in the datasheet.
> 
> The Datasheet says for this connection on page 6:
> "[...]Finally, the  oscillator may be soft synchronized by negative
> pulses applied to the threshold voltage pin (pin 9 of 3340[...]). These
> pulses cause the triangle upper peak to reverse direction prematurely,
> causing the oscillation period to be an integral multiple of the pulse
> periode. [...]"
> 
> So according to the Doepfer schematics, the Curtis datasheet and - as
> minor argument - to my experience, a simple short pulse is perfect to be
> used as soft syncs master signal. Of course a saw will do something
> similar, but that shouldn't prevent you to try a pulse. ;-)
> 
> Florian

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