Russell KramerI wanted a bright colourful video output that responds to the audio. What I came up with was a phase-shift-oscillator. It produces three sin waves each 120° out of phase with each other. This produces a rainbow effect when applied to the R,G,B inputs. The circuit produces vertical rainbow bars because it phase-aligns to the Hsync pulses due to a sympathetic oscillation with the porching circuit. By applying audio I can push the oscillation out of phase and produce responsive patterns.
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Hi, this is awesome! Did you use a tl074 for the phase shifter? Thanks!
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Yay ! ring oscillators ! I'm also playing with them at the moment :-)
https://hackaday.io/project/9779-yet-another-electronic-lampyridae
Have fun !
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BTW I learnt the hard way to watch what I connect into the virtual ground node with high impedance in my ultrasonic project. The coupling caused unwanted coupling and oscillation in my design.
I understand you are trying to make oscillator, so this might not matter to you.
Your *unbuffered* *non-decoupled* virtual ground with 50K dividers has an impedance of 25K. Those 1uF caps can inject signals (your audio input and the output of the 3 opamp) into the virtual ground. You can connect the cap to GND instead.
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