This circuit with two operating modes was found in the September 1989 issue of Radio Electronics magazine. Other operational amplifiers can be used. The power supply must be dual.
The circuit shown in the figure was suggested by National Semiconductor in its 1994 Linear...
This circuit can be controlled by an LDR causing an LED to flash at a frequency given by C2. The...
This hybrid power supply circuit was found in the August 1997 issue of Electronics Now magazine. The...