Low noise amplifier (T466E)

Found in 1948 MIT documentation, this 4-tube amplifier is characterized by its low noise level.

Antenna Amplifier (CB4172E)
The suggestion for using this circuit from an old American documentation is to use small antennas...
Precision Phase Shift (CB5440E)
We find this circuit in a 1980s documentation. The integrated ones are of the time and their...
Code Practice Oscillator (CB1429E )
Found in a 1975 radio amateur publication, this simple oscillator is for code practice. The PNP...