We find this circuit in American documentation from the 1980s. It consists of a frequency folder using a varicap. The capacitors and coils depend on the frequency of operation.
Found in a 1980s telecommunications documentation, this balanced modulator circuit uses...
This circuit was found in a 90’s 303 Circuits. The components are from the period and the heating...
This simple receiver that works with only 1.5 V, was found in a 1987 documentation. The integrated...