This high impedance headphone amplifier was found in American documentation from the 1990s. Any general-purpose FET can be used.
Found in National Semiconductor documentation from the 90s, this circuit makes use of components from...
This circuit was originally designed to measure capacitance with an ICL7107 but can be used with...
The TDA7000 is a Philips integrated circuit that contains a complete FM receiver with the need for...