We found this circuit in a Texas Instruments documentation from the 80s. The circuit uses simple power source and the frequency depends on C1 and R1 basically.
This circuit is from an Electronics Now from the 90s. The circuit uses a power integrated circuit...
Although newer voltage regulator integrated circuits exist, the uA723 is still very common in...
This amplifier has an input impedance of 20 M ohms. We found it in documentation from the 1980s. The...