This variable filter circuit was found in July 1975 Radio Electronics magazine. The circuit uses 3 general purpose op-amps like the 741 and must use a symmetrical source.
This circuit was found in a 2005 Linear Technology component manual. The circuit is full bridge...
The source used in this timer is of the type without transformer and regulated by the 7 W zener. The...
This circuit detects the sound of thunder, assessing its intensity and thus the distance of a...