This high-Q low-pass filter was found in the October 1990 issue of Radio Electronics magazine. The frequency depends on the capacitors used and is on the order of a few tens of hertz.
Suggested by General Electric in a 1970 document, this circuit uses a LASCR, or SCR fired by...
This circuit is from a Popular Electronics from the 90's. The circuit activates a buzzer with...
Division of a digital signal up to 4098 can be done using the 4040 IC as shown in Figure bellow....