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Doepfer

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AW: [Doepfer_a100] Re: A147 not working anymore

2008-08-12 by hardware@doepfer.de

> well I tried that, replaced the CA3080 from a working A147..
> still not working... and for
> the other circuits its not possible. The two others A147 I have
> are different versions than
> the one not working, the components are directly soldered on the
> pc board...
>
> so... i'm affraid I have to send this modulein for repair...
>
> I checked all other components and nothing seems unsoldered or missing....
>
> Best,
> Alexandre

The modules with the directly soldered circuits are probably older ones
(manufactured before ~ 2000) as we use sockets for all circuits since many
years for easier service.

Only the upper of the two remaining integrated circuits (IC2/TL084) is
required for basic operation. The lower circuit (IC3/TL064) is used only to
generate the waveforms sine and sawtooth. It can be removed for testing
(sine and saw will then not work). The TL084 (quad OpAmp) is used in many
A-100 modules. Maybe you have a module at hand from which you can borrow the
TL084.

If even this will not help the module has to be sent in for repair.

Best wishes
Dieter Doepfer

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