This is a simple tubed mixer from the 50's. The circuit does not include the power supply and has 3 inputs with independent controls. The tubes are double and the inputs are high impedance.
This notch filter or reject filter rejects signals of a certain frequency with good selectivity. The...
The purpose of this circuit, which we find in a 1975 radio amateur publication, is to measure the...
The coils of this simple mid-wave radius are wound 28 or 26 on a 12 to 30 cm long ferrite rod and the...