We found this circuit in the October 1994 issue of Electronics Now magazine. The circuit uses a now-uncommon 4046 PLL and the gates of a CMOS 4001.
This configuration from the 1970s can be applied to modern equivalent operational amplifiers. The...
This simple alarm using only transistors was found in a 1990 publication. It can be powered by D...
The circuit presented was found in the 1994 National Instruments Linear Applications Handbook and...