This circuit with power MOSFETs was found in a 1980s Siliconix documentation. Equivalent MOSFETs can be used, as well as other transistors. Note the symmetric power supply.
When the illumination decreases, this multivibrator starts up, causing the lamp to blink at a...
Found in Radio Electronics, this simple indicator circuit uses general-purpose transistors common today....
November 2016 - Mouser Electronics is makingToshiba's new TLP78x and TLP79x isolation amplifiers...