The circuit is from a Radio Electronics magazine from October 1987. The Triac must be equipped with a heatsink and the transistors are general purpose.
This filter was obtained from a Linear Technology manual from the 1990s. The power supply must be...
Found in a 90s Popular Electronics, this circuit is intended for amplifying analog video signals....
Based on a 555, this 80's American documentation circuit detects the voltage of a battery and can then...