This is the basic configuration of an operational amplifier sample & hold circuit. The FET and transistor are commonly used. The circuit is from an 80's documentation.
In the figure we have the typical configuration of a sinusoidal audio oscillator with twin-T. The...
This electronic game was found in a 1996 documentation, but it can be easily assembled today, both...
This circuit is from an August 1984 Radio Electronics magazine. It monitors the state of a RAM...