This power supply protection circuit using a relay was found in a 1967 documentation. The components are from the time, but current equivalents can be used depending on the power source current.
Found in National Semiconductor publication from the 1980s. This gain-100 circuit can be...
We found this configuration in a 1975 publication. It can be implemented easily, as it uses only...
The high number of transistors on this radio for the medium wave range is an indication of its...