This circuit was found in the February 1983 issue of Radio Electronics magazine. It is a 4-digit circuit with dedicated integrated circuits, with no power supply indicated.
This amplifier was found in a 70s documentation. The product gain x bandwidth is 350 MHz. The...
This circuit mimics the trill of a bird. We found it in an American documentation from the 90s. It is...
With the values indicated for this circuit, the lamp will flash 60 times per minute (1 per...