Serge 73 - 75 Homebuilt VCO Input and Output Question

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Serge 73 - 75 Homebuilt VCO Input and Output Question

Post by harolddonnelly » Tue Aug 13, 2019 7:25 pm

Hi all,

I've been looking through the old serge documents and I've been able to figure out what most of the inputs and outputs are on the VCO module are but I'm not 100%.

Any insight would be greatly appreciate from people who have built the Serge 73-75 Homebuilt.


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Post by diophantine » Tue Aug 13, 2019 8:53 pm

The two upper-left outputs (with the sine symbol at the top) are the variable outputs.
The two outputs below are saw outputs.
For each of those sets, one output is AC coupled, and the other is DC coupled.

With the variable output, the pot is summed with the CV input to control the variable output (i.e. pot is not an attenuator).

The two CV inputs are NOT 1V/Oct, but yes, they are frequency CV inputs and the corresponding pots are attenuverters for those signals.

And at the bottom is the sync input & the initial frequency pot.

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Post by mestlick » Mon Aug 19, 2019 2:21 pm

The CV inputs are not even exponential, so you can't sum voltages and get equal intervals (meaning you can't transpose a sequence on one input with an offset on the other input).

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