This circuit comes from a Gernsback Publications of the 90s. The circuit uses a general-purpose transistor as a sensor. The power supply must be symmetrical.
This circuit was found in an Analog Devices publication from the 1990s. The circuit performs input...
Found in Motorola documentation from the 90s, this circuit can be implemented with current...
We found this circuit in an old documentation for hams. In it we have the way to use a varicap to...