Graphic oscillator - waveform mixer

7-48 - elektor july/august 1982 "And we don"t mean graphic equaliser". An oscillator operating along similar lines to an equaliser. In the case of the latter, a set of slide potentiometers adjust the frequency response and the waveform mixer level can be directly deduced from the position of the levers. Here slide potentiometers are used as well, only now for the purpose of setting the waveform on the screen. To understand the object of the graphic oscillator the circuit diagram should be looked at "back to front". P2 ... P17 sets the DC voltage in the 0 ... 5 V range. Electronic switches ES1 ES16 feed the voltages to the output of the circuit. Normally speaking, the article should end here, were it not that the circuit has an additional interesting feature to offer • .. When an oscilloscope is connected to the output, a waveform appears on the screen that can be adjusted to contain up to 16 steps. Fortunately, this does not have to be done manually for the remaining component...