Noiser
Noise generator project, used as pcb making and soldering exercise.
4093 quad nand gate + 555 timer.
A 4093 has 4 nand gates, each of which can be used as an oscillator.
Assume nand gates are named A, B, C, D. The idea is to connect the oscillators so that A modulates B, C modulates D, and B and D outputs are mixed together to modulate the 555 timer.
A potentiometer controls the frequency of each nand oscillator, and one potentiometer is used to voltage starve the chips (= between power source and chips - this causes them to fail in funny sounding ways out when the power is lowered too much - only include this if the effect is noticeable with the used chips)
One potentiometer is also used for volume (we don't want a roomfull of these at full volume - they are _loud_ at 9V).
It might be interesting to control the volume envelope too..
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