Using the 741 this basic circuit was found in the November 1973 Radio Electronics magazine. The power supply must be symmetrical. The components can be recalculated for other frequencies.
This Nixie pipe circuit was found in 1965 documentation. Note the high supply voltage. Appropriate...
This circuit is from a 1976 publication, but it can be assembled with modern components. For the...
Found in Popular Electronics from the 90's, this circuit consists of an audio oscillator for Morse...