Table of Contents

Pointers

Fabrication Info

DifficultyRating: 6 / 10

Components 61
Resistors 34, 2 Thermistors
Capacitors 3 Electrolytic, 4 Polyester
Diodes 3
Transistors 8
ICs 3
Other 1 Pot, 1 Switch, 2 Trim Pots

Be careful, there are 4 different kinds of transistors on this circuit. Make sure you get the right one in the right place. After you build the VCO, it is a good idea to Test the circuit after you build it, this will make tesitng (and troubleshooting, if you have to) the other sections much easier.

Additions

You might want to mount Q8 on a SipSocket, so that you can put a HighGainTransistor in there.

If you are unsure of your soldering skills, you can also mount the 3 ICs on DipSockets. Also, if in the future one of these ICs were to fail, you will be glad you socketed them!

According to the build manual when the sawtooth and squarewave are tested, R36 is not yet soldered in, but on the fotos it is there. It's a good idea to have R36 soldered when testing to get the correct waveforms and DC bias.

Mistakes to avoid

equaliser says… The picture in the fab manual for the 2SK30AO transistor is actually of the AY transistor, which I soldered instead of the AO. Ignore the pic - you need the AO in the VCO.

Schematic Power Supply Voltage Controlled Oscillator Voltage Controlled Filter Envelope Generator Voltage Controlled Amplifier Headphone And Mixer Digital Sequencer Midi, USB and Sync
Fabrication Building the Ps Building the Vco Building the Vcf Building the Envelope Building the Vca Building the Headphone And Mixer Building the Sequencer Building the Midi and Sync Finishing It Off
Testing Testing the Ps Testing the Vco Testing the Vcf Testing the Envelope Testing the Vca Testing the Headphone And Mixer Testing the Sequencer Testing the Midi and Sync
Mods Ps Mods Vco Mods Vcf Mods Envelope Mods Vca Mods Headphone And Mixer Mods Sequencer Mods Midi And Sync Mods Finishing Mods