This two-digit (up to 99) circuit divides a signal by values programmed by the BCD switches. The circuit comes from a Radio Electronics from February 1989.
This basic configuration of voltage regulator using operational amplifier and zener was found in a...
This 75 W power supply was found in American documentation from the 1980s. Transistors can be...
This circuit was found in a 1987 magazine. It measures the pulse rate produced by a cardiac...