Using a 4046 PLL, which is uncommon today, this circuit was found in the October 1994 issue of Electronics Now magazine. The circuit can be modified by changing the capacitor.
Found in an English documentation from 1989, this circuit uses components common today. The...
The LED frequency flashes depends on the value of the capacitor tested according to the table. We...
Found in a Popular Electronics from the 90s, this circuit generates a signal that depends on the...