We found this circuit in an American documentation from the 1990s. The circuit is based on the LM3909, a low power oscillator from National Semiconductor.
This circuit was found in a 1986 publication. The speed of the effect is determined by the 555,...
This preamp version uses BC109 transistors that are older versions of the current BC549 in plastic...
This simple voltage-controlled oscillator generates signals from 300 Hz to 1,500 Hz with voltages from...