Found in a 1969’s Electronic Design, this circuit operates in a narrow range of voltages. Transistors can be replaced with modern equivalents.
With this luminous remote control, which we found in a 1990 publication, using a flashlight you...
We found this circuit in a 1967 Electronics World. The circuit can be designed to control other...
This circuit can be used in a signal level indicator with LEDs. The circuit is from an Electronics Now...