Doepfer

Hi Josue

> You are wrong about the A111...The A111 uses a CEM 3340 but the module
> is not a raw CEM module, it have circuits around the sync inputs,
> comparators I think so it needs to see a rising or falling edge as all
> VCOs.
> 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