This circuit was found in a 1945 publication. The circuit was stated to be part of a walk talkie. Note that, as it is a portable assembly, it was powered by batteries. The jack was for microphone insertion.
The integrated circuit used is a dual 555 CMOS. The circuit is from an English documentation and...
A 3-input OR gate can be made with an LM3900 amplifier, as shown in the figure. The purpose of the...
We found this conventional power source with a regulating transistor in a 2002 documentation. The...