A very simple tone generator which uses two RC networks connected in series to obtain the necessary phase shift can be designed using this circuit diagram. Frequency range of the tone generator is between 20 Hz and 20 kHz, and distortion is kept to a minimum by using additional stability in amplitude.
A very simple electronic circuit that imitates sound of a cricket can be achieved using this electronic scheme. The circuit contains four oscillators, the first, N1, take note of the acute. The frequency of this note is fixed with potentiometer P1, so that it is in the range of a resonant piezo buzzer: the sound is therefore stronger.
To get the sound of a cricket, 4 kHz rectangular output of N1 is modulated in amplitude with a frequency of 10 ... 20 Hz, produced by N2 oscillator frequency shift and how numeric N4.
A very simple audio mixer can be designed using this circuit diagram electronic project. Audio mixing is normally performed by a mixer with virtual ground, in which the various input signals are applied through series resistors to virtual ground, that at the inverting input of operational amplifier. The audio mixer is a little different and uses the principle of common ground, the input voltages are converted into alternating current which, when summed, is the AC component of the collector.