Doepfer

For each output a scale control is available to adjust the scale of the
output in question. It also limits the max. voltage. With the controls fully
CCW the max. voltage is close to +12V. To limit the voltage to +5V the
controls have to be adjusted to about position 4. I'm not familiar with the
Model D but I don't think that voltages beyond +5V can damage the unit
(without obligation).

Best wishes
Dieter Doepfer

> -----Ursprüngliche Nachricht-----
> Von: Doepfer_a100@yahoogroups.com [mailto:Doepfer_a100@yahoogroups.com]
> Gesendet: Freitag, 4. Januar 2019 07:24
> An: Doepfer_a100@yahoogroups.com
> Betreff: [Doepfer_a100] A-198 Trautonium / ribbon controller - output
> voltages
>
>
>
>
> I've ordered the A-198 Trautonium manual / ribbon controller, and
> will hopefully get it early next week.
>
> I looked in the manual, and on the main web page, expecting to
> see what the output voltage ranges are for the two CV and two
> Gate outputs - but I don't see any mention of them.
>
> I have a small, mostly Doepfer based modular system, which I
> could connect it to, but I was also hoping to use it with my
> Behringer Model D, which is semi modular but expects inputs
> mostly in the range 0-5V.  Allegedly, going outside the specified
> range could damage it, so I need to know what voltages I'll be
> dealing with.
>
> Are the outputs always positive?  Do they go as high as 12V (or
> maybe as low as -12V)?  If not, do they have guaranteed limits?
>
> I can see I might need to make something, like fixed potential
> dividers, to scale the voltages, but I will need to know the details.
>
> What's the output impedance of those four outputs, and what's a
> safe or reasonable load for them, in mA?
>
> What's the expected voltage range of each output?
>
> - Andy
>
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>
>
>
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>

Hi Andy,

you find my answers written inline.

Best wishes
Dieter Doepfer

> Hi Dieter,
>
> Thanks.  Are the outputs always a positive voltage?

The Gate and the pressure CV are always positive.
The position CV becomes slightly negative (about -1V with the scale control
fully CW) in the Hold Off mode when the position sensor is not touched.

> The Behringer Model D manual states that exceeding the rated
> input voltages can damage it.
>
> I have no way of knowing if that's true, because I haven't seen
> the schematics of that either, but I'd rather not rely on it
> being wrong, or on me not turning the scale knobs past 4, so I
> want to make up some fixed value attenuators, or similar, to make sure.
>
> Are the outputs direct from an op amp, or is there a resistor
> between each op amp and the output socket - or is it more
> complicated than that?

There are 10k potentiometers as attenuators at both CV outputs. The output
sockets are connected to the center terminals of the potentiometers.

> - Andy