The circuit shown is from 1994 National Semiconductor documentation but can be implemented with more modern operational amplifiers. The power supply must be symmetrical.
Found in a 1964 CQ magazine this circuit consists of an automatic telegraphic key, providing the...
This is the minimum amplifier configuration with the LM380 and can provide an output of up to 2.5...
The UM3562 integrated circuit (not very easy to find) synthesizes three types of sound that...