C
The combination of rectangular signals of different frequencies and intensities can result in signals of very complex waveforms. If the signals are of low frequencies and kept in digital form with maximum intensity, we can have in this combination the production of random pulses. This is precisely the purpose of the circuit shown in the figure. In this circuit, we use the four NAND ports of a 4093 to generate 4 signals of different frequencies that can be adjusted through four potentiometers. These signals can also have their intensities adjusted separately through 4 other potentiometers. Thus, we obtain a complex signal at the output whose waveform and intensity will depend precisely on all these adjustments. By connecting an oscilloscope to the circuit output, the reader can observe the waveform being generated. We can say that it is a very economical waveform generator for testing equipment on a bench. Of course, there is still the possibility of using a 4093 second with the combination of four other signals, in which case the waveform becomes even more complex. The device's consumption is very low which allows it to be fed with batteries or even a common 9 V battery. We observe that the maximum frequency of the oscillators is determined by the CMOS power supply being around 4 MHz for this circuit. The capacitors will determine the frequency range generated.
