DIY Synth Modulation – Using CD4093 to Shape and Modulate Square Waves

In this episode, we take our DIY synth to the next level by adding modulation and tone shaping using the CD4093 NAND Schmitt Trigger IC! If you’ve followed the first two projects — the VCO (CD4046) and the Sequencer (CD4017) — this one introduces how to modulate one oscillator with another to create richer, evolving sound textures. The CD4093 works just like the CD40106, but with two inputs per gate, allowing it to act as a modulator or logic-controlled oscillator. You’ll hear the difference as we combine oscillators to make complex waveforms and dynamic timbres. 🔧 Parts Used: CD4093 NAND Schmitt Trigger IC 10 kΩ potentiometer 0.1 µF capacitor CD40106 (used as modulation source) 1/8" audio jack 9 V battery or supply Breadboard + jumper wires 💡 What You’ll Learn: How to use the CD4093 as a square-wave oscillator How logic inputs control oscillation states How to modulate one oscillator with another for richer tones How to combine your previous circuits (VCO + Sequencer + Modulator) ⚡ Pro Tip: connect your CD40106 oscillator output into the input of the CD4093 for live modulation — this creates a form of FM (frequency modulation) that adds texture and movement to your sound! Materials + Schematic : https://www.facebook.com/notes/philstudio/season-1-episode-4-gate-modulating/1683160301699233/ Datasheet : http://www.ti.com/lit/ds/symlink/cd4093b.pdf #diysynth #diyaudio #electronicsprojects