The purpose of this circuit found in an old Elektor is to light a lower power lamp when the bigger one burns out. The loads depend on the triacs.
This circuit was found in the January 1989 issue of Radio Electronics magazine. The circuit sends...
We found this TTL power supply circuit in the December 1972 issue of Radio Electronics magazine. The...
This circuit was found in an American documentation from the 1980s. The sensitivity ranges from...