We found these circuits in a Popular Electronics from the 90s. The circuit has a simple low power version and a higher power version with MOSFET (VMOS) of the time.
This 1 kHz oscillator was found in the February 1970 issue of Radio Electronics magazine. It uses...
The 723 integrated circuit is manufactured by several semiconductor companies with different...
This is a combined circuit of tone generator and preamplifier. We found it in a 1975...