We found this circuit in the July 1969 Radio Electronics magazine. The circuit uses a coupler made with a lamp and an LDR. The power of the lamp determines the types of diodes.
This circuit activates an incandescent garden, balcony or showcase lamp when it gets dark, turning it...
This circuit is from an old publication of 1972 but can be mounted with BC548 transistors for 12 V...
This circuit is intended for the testing of junction FETs, providing several reading options...