This is the 4093 circuit as shown in the diagram below with two main Oscillators, each with inputs for variable resistors (one of which is an LFO). On the other side there are two alternate LFO's each also with inputs for resistance. The oscillators are being used together for additive synthesis. The first of which is shown here as an on board LED that blinks at a photocell. The photocell is also capable of detecting any other light source such as a laser. The second Oscillator input comes from the XBee Radio and (not shown), each of these inputs can be used to Amplitude Modulate the Sum of the two main Oscillators, and at a high enough frequency becomes additive as well - giving the main LFO a powerful timbrel effect.


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This is a circuit diagram of an R/C NAND gate (otherwise known as a schmidt trigger) being used as an oscillator with one square wave amplitude modulating or gating another square wave and an optional third and fourth gate that are switchable in the cascade. The diagram depicts third gate uses a photocell to measure resistance while the fourth gate uses signal coming over RF to a Xbee radio to determine the resistance.