We found this circuit in the November 1984 Radio Electronics magazine. The base frequency is given by C1. The power supply can be between 3 and 12 V.
This circuit uses a PLL4046 oscillator to excite a piezoelectric ceramic. The circuit is from an...
This circuit already explored in several diagrams in this section was found in a 90’s Popular...
This logic probe or logic level indicator is suitable for use in CMOS circuits. The power comes...