This variable frequency oscillator with the 4093 was found in a Popular Electronics from the 90s. The table gives the component values for various frequency ranges.
This circuit was found in the October 1994 issue of Electronics Now magazine. The 40446 IC is a...
Found in a 1967 EEE, this circuit generates a constant amplitude signal, stabilized by a zener...
This circuit is from the November 1974 issue of Radio Electronics magazine. The capacitor...