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AW: [Doepfer_a100] A-143-3 modification

2011-07-19 by yahoo@doepfer.de

> Hi there
>
> I'd like to add reset/sync and maybe CV input jack sockets to my
> beloved A-143-3 quad LFO.
> Could anyone please let me know where to connect these inputs on
> the PCBs, or maybe supply me with schematics ?
> It would help me saving investigation time.
>
> Many thanks in advance for the help.
>
> Best regards,
> Constantin

The A-143-3 circuit is very simple and based on the well-known
integrator/Schmitt trigger combo. It is not very easy to add a reset/sync to
this circuit and more complex than the main LFO circuit. One has to
discharge the capacitor very fast and to give the LFO a kick into a certain
direction (otherwise it would continue with the latest direction). And to
have available voltage control a totally different circuit is required.

But we are working on such a module (A-143-4 Quad VCLFO/VCO) but I don't
know when it will be available.

Best wishes

Dieter Doepfer

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