We found this CMOS circuit in a 1978 publication. It allows you to use a standard calculator keyboard with 16 keys for encoding in hexadecimal.
The output current of this power supply depends on the power transistor and the transformer and...
This voltage inverter uses a small transformer. The circuit was found in the April 1995 issue of...
This 1969 Popular Electronics circuit was based on the then recently released BC109, today with...