Now that I have all components available, I was able to build up the three VCOs, attaching the small boards with the according connectors to the main board:

Main Board, VCO 1, 2 and 3 with Small VCO Boards Mounted Main Board, VCO 1, 2 and 3 with Small VCO Boards Mounted

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Main Board, VCO 1, 2 and 3 with Small VCO Boards Mounted

Component side, jacks, switches and sliders still missing.

Main Board, VCO 1, 2 and 3 Completed Main Board, VCO 1, 2 and 3 Completed

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Main Board, VCO 1, 2 and 3 Completed

Back side, jacks, switches and sliders still missing.

Meanwhile I had also finished the VCF part. As you can see I'm not using the built-in power unit, but will be using my own external power supply:

Main Board, VCF Completed Main Board, VCF Completed

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Main Board, VCF Completed

Component side, jacks and sliders still missing.

Main Board, VCF Completed Main Board, VCF Completed

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Main Board, VCF Completed

Back side, jacks and sliders still missing.

With those parts done, I could do some first test. I've connected the main board to my power supply and connected things to my oscilloscope:

Mainboard VCOs and VCF Testing Mainboard VCOs and VCF Testing

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Mainboard VCOs and VCF Testing

Happily all seems fine so far. The correct waveforms are visible for the three VCOs and also at the output of the VCF. In the following images the upper yellow waveform is the VCO output and the lower blue waveform is the same signal passed through the VCF.

VCO 1, square waveform:

Testing VCO1 Square Signal and VCF Output Testing VCO1 Square Signal and VCF Output

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Testing VCO1 Square Signal and VCF Output

VCO 2, triangle waveform:

Testing VCO2 Triangle Signal and VCF Output Testing VCO2 Triangle Signal and VCF Output

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Testing VCO2 Triangle Signal and VCF Output

VCO 3, saw waveform:

Testing VCO3 Saw Signal and VCF Output Testing VCO3 Saw Signal and VCF Output

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Testing VCO3 Saw Signal and VCF Output

So far thus no soldering errors, all seems to be working as it should.


Built with Pelican · © 2025 Peter Kamphuis