This circuit from a 1967 documentation generates 2.5 Hz signals depending on the capacitors used, in this case 160 uF. For 4 6700 pF the signal will be 20 kHz.
Found in an EDN from the 90s, this circuit uses an electret microphone. The output can be used to...
This circuit is characterized by the configuration that accelerates the switching, being ideal for the...
This circuit makes use of a PLL 567 to invert the phase of a signal, ie to change it from 0 to 180...