This simple general-purpose transistor mixer was taken from an article in Electronics Now magazine in March 1994. You can choose a low-noise transistor such as the BC549.
Combined with the two previous circuits, we can create a simple multimeter with this circuit. The...
This 1.5V instrumentation amplifier was found in National Semiconductor documentation from the...
This simple circuit helps to save incandescent lamps by leaving their filament slightly heated and thus...