Sub page: analog percussion
designed and build around 1985

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Description: Very simple analog percussion/filterbox. using only 1 transistors and R+C+diode. Twin-T filter in feedback creates resonance. A diode is used as a variable resistor to sweep the resonance for the pitch envelope type of sounds. Via the pushbutton or the external trigger input you create a pulse that is exciting the filter. External audio can alse be routed through the filter. Current consumption is 0.3mA so it runs >1000 hours on the build-in 9V battery.	Sound examples (direct output, no effects) manual trigger manual trigger ext trigger ext trigger ext trigger ext trigger ext trigger
	Here is the circuit drawing I found: anperc-circ.jpg